North American Aviation P-51 Mustang

SERI ES EDITO R: T ON Y H O LME S

PRODUCTION LINE TO FRONTLINE·

1

NORTH AMERICAN AVIATION

P-SI

MUSTANG Michael O'Leary

tmmm AVIATION

FRONT COVER With a mi ni m um

of celeb ration. a worker applies a rather crude number 10.000 to ident ify the 10.OOOth Mustang as it rolls off t he pro duction line BACK COV ER W ith cow lings

neatly stored aboard the Wabash Cannon Ba/l, a facto ry-fresh P-S ID has its Packard Y- 16S0 fired up fo r th e first time afte r its attachment to the airframe

First publi shed in Great Britain in l Y~8 by Osprey Pub lishing Elms Co urt . Chapel Way, Batley, Ox ford OX2 9LP Un ited Kingdom 0 1998 Osprey Publishing Limit ed

All right s reserved . Apart fro m any fair dea ling for the pu rpose o f privat e study, research , criticism o r review, as per m itted unde r t he Co pyrig h t, Design and Pate n ts Act , 198H, no par t o f thi s pu blication ma y he reproduced, stor ed in a retri eval system , o r t ran smitted in any form or by any m eans, electronic . e lec t rical, c he m ical. m ech an ical. optica l. photocopying , recor ding o r oth e rwise, witho ut prior writt en perm issio n . All e nqui ries sho uld be add ressed to th e publi sh er. ISBN I 8553 2 7£H 1 Edited by Tony Holmes I'agc design by Gwyn Lewis Scale Drawings by Arth ur Bentley and Mark Sty ling Prin ted in Hong Kong

ED ITO R's NOTE

To m ake th is new series as au t horitat ive as poss ible, th e ed itor would be ext remel y interested in hea ring from any ind ivid ua l who m ay have relevan t pho tog rap hs, docume ntat ion or first-ha nd ex perie nces rela ting 10 th e elite pilots, a nd their a ircraft, of the va rious th ea tres of war. Any material used w ill he fu lly cred ited to its origin al sou rce. Please writ e to To ny Hol m es at 10 Prospect Road, Scvcnoa ks, Ke nt , TN I3 :~ U A , Un ited Kingd om . FOR A fREE CA T.-\LOG UF. OF ALL fIOO"-~ l'U IILlSHF.O BY O SPREY PLf...\SF. WRITI TO:

The Mark eting Manager, Os prey Puhlishing Limit ed, P.O. Box 140 Wl'Ilingb orough , Northa n ts NN8 4ZA

'-

CONTENTS

INTRODUCTION 6

THE PROTOTYPE 8

C H A PTE R 2

BUNDLES FOR BRITAIN

C H A PT En 3

PONY SOLDIERS 30

C HA PT ER 4

ON TO BERLIN 47

C H A PT ER 5

BUBBLE TOP 75

C H A PT ER 6

FRONTLINE

105

C H,\ PTER 7

MUSTANG MEN

APPENDICES

126

136

17

INTRODUCTION

W ELCOM E TO T HE FIRST VOLUME in an exc iting new se ries from Osprey. From Production Li ne to Frontli ne was con-

ceived in late 1996 when th e aut hor and ed itor Tony Ho lmes we re go ing through an ex te ns ive co llec tion o f North American Aviatio n P-SI Mustan g p ho tog raphy. Arguabl y one of th e m ore attractive aircraft to come out of World War

2, we were taken by the way t he fighter was created to a British specificatio n in a fairly sho rt space of time, and then we nt on to becom e a mass-produced co mbat classic. There have been n umerous books written o n th e Mustang ov er th e yea rs, but we wan ted to a pproac h th e aircraft from a rather unique perspect ive - its pro d uct ion life. America's direct involvem ent in World War 2 was und er fo ur years, yet in that very shor t tim e period a lifestyle was create d th at would effect fut ure gene rations . The nati on made a massive shift from a mainl y agricultural econ om y to an indust rial giant dur ing th ose few years, and the ra pid ly emerging aviation com pan ies took full advant age of th e lessons of Henry Ford to ap ply mass-p rodu ction techniques to th e building o f aircraft. Los Angeles became on e of the world's major centres for th e p rodu ction o f combat aircraft, origina lly sta rting with desperate orders from the French and British, and th en mov ing in to m assive co ntracts from the US Army Air Force and Navy. With excellent weat her, chea p land prices and an increasing pool o f available workers, aviation co mpan ies bega n huge expansio n programmes, wh ile hi ring tens o f thousands o f new workers. For the first tim e women became a major influence in the wor k place as th ou sands of 'Rosie th e Riveters' were hired to take the place of men go ing into th e mi litary. Barely recovering from the Grea t Depression, families were suddenly taking in more mo ney than they had ever seen. Life styles and con cepts were cha nging, and America wo uld never be th e same agai n. 6

P-S I MUSTAN G

In t his volume we follow the saga of t he 1'-5 1 productio n through a fairly uniqu e series of photographs. In orde r to place the product in its inten ded env ironme nt, we also presen t ph ot ographs of th e Mustang in co mbat. We have used the Wor ld War 2 period as a cut-off date fo r this first volume o n the P-51 , since we wanted to show the aircraft in the global situatio n for which it was design ed - a seco nd volume, featu ring th e experi men tal lightweigh t Musta ngs, 1'-5 1F/H, 1'-82 Twin Musta ng and po stwar F-5 1Ds is plan ned for 1999. I would like to take the o pportunity to thank some indi vidua ls wh o helped make this boo k possible; Gen e Boswell of North Ameri can Rockwell, who realised the im portan ce of preserving some o f the images seen on the se pages; Pete Regi na, Lowell Ford, Simo n Brown , Bruce Lockwood, Alan Preston , David Price and Carl Scho ll, who all provided valuable in form ati on; a nd Scott Bloom for the pro vision of th e vintage Mustang advertisemen ts. We look forward to receiving your com ment s on this

book, and since there are numerous other vo lumes plann ed for this series, we wo uld appreciate yo ur inpu t with memories, documents and photograp hs. Queries to th e aut hor sho uld be add ressed to Michael O'Leary, 1'0 Box 6490 , Wood land Hills, Californ ia, 91365, USA.

Michael O'Leary Los AI/geles May 1998

tNTRODUCTION

7

CHAPTER

rn THE PROTOTYPE

BY M ID-O CTOBER 19 40 , Nort h American Aviation (NAA) had become firml y establi shed at Mines Field in so ut he rn Ca lifo rn ia - th e airfield that is n ow Los Ange les Intern at io na l Airport. Building their rugged NA- 16 series of t ra in ing air craft , NAA h ad decided to move from Ma ryland to join th e many ot her avi at io n co m pa n ies th at h ad establis hed facilit ies in southe rn Californ ia, and Mines Field was picked because i t offered a n estahlished airfield t hat was not only clo se to su pply sou rces bu t was also ch ea p (NAA's 20-acre site was leased to th e co m pa n y fo r th e pr in cely su m of 5600 per yea rl). Th e new NAA factory was opened in 1936 a n d co ve red 159,000 square feet, wh ile I SO em ployees became en gaged in prod uctio n of th e NA-16 train er and the por tly 0 -47 observa tio n a ircraft. Th e ma ny p rob lems t ha t plague a new com pa n y we re co nquered by NAA p resident Ja m es H 'Dutch' Kindelberger an d h is sma li hard-wo rkin g staff. Britain had beco m e in terest ed in th e NA-16, which had turned into t he AT-6 Texan, a nd in 1938 began ordering the stu rdy adva nce d tra in er fo r the Roya l Air Force (RAF) and o t her Com mo nwe alth air forces as th e Harva rd . Because of the rapidly esca lating te n sio n s with Hit le r's Ge rm a ny, the Eu rop ea n na tions we re rearmi n g at a n un precedented pace a nd at tem ptin g to bu y as mu ch m ilitary eq u ipme n t as pos sible. Brit ain h ad orde red th e Cu rt iss P-40 Tomahawk a nd , becau se o f t he large orders, was inte rested in perhaps h avin g NAA build th e type under lice n se. The small, hut creative, NAA ma na gem e nt team decid ed that it wou ld be much mo re ben eficia l to t he co m pany to create th e ir ow n fighte r for t he RAE What t hey wa nte d to do was ta ke the Aliiso n V- 17 1O (at the ti me t he most powe rful V-12 in product io n in the USA) a nd wrap it arou nd a new airfra me th at wou ld out str ip t h e P-40 in pe rfo rma nce. In 1936, NAA h ired a new employee - Germa n-born Austrian Edgar Sch mu ed . For a b it o f co nf using co m pa ny h istor y, we mus t go back to the la te 1920 s when Ge neral Moto rs (GM) created a h o lding com pany wit h th e na me No rt h America n Aviatio n. Th is co m pa ny exis ted so lely to acquire stock in o t her 8

P-5 1 MU STANG

aviatio n co ncerns - giving GM a possible sho t at con trolling t he rap idly emerging aviatio n market. In 1929, NAA took over the Jok kcr Aircraft Co rpora tio n and Sch mu ed, who wo rked for GM as a field service man ager in Brazil, moved to the USA to wor k with aircraft - so meth ing he had always wanted to do , with his training as a mech anical engi nee r. Fokker soo n becam e Gen eral Aviatio n, hu t th e Airmail Act of 1934 forced airm ail car riers to rid th emselves of ho ld ings that controlled aircraf t construction . Th is mea nt tha t GM ha d to get rid of NAA which, in turn, too k over General Aircraft. Kindelbe rger had co me from Douglas Aircraft a year ea rlier, and was now presiden t of th e 'new' NAA. 'Dutch' moved t he co rnpan y west and asked Schmued to join him, bu t Sch rnued 's wife did not wan t to move to Californ ia so the designe r join ed th e firm of Bellanca - a de cision he soon regretted. However, ' Dutch' had kept t he job offe r open, and Sch mued and his famil y finalJy moved west. However, just 100 miles fro m Los Angeles, th e family was in volved in a serious car accident which killed Sch mue d 's wife and left the designer scriously injured - it took him un til February 1936 to recover. Once British in teres t in t he ne w fighter de sign had beco me more so lid ified, t he p roblem of crea ting a new airframe aroun d th e V-17 10 was th e type o f challenge en joye d by Schmued . Th e inline V-12 req uired a large rad iator for coo ling, and its placement cou ld great ly affect performance - to the positive or negative. At the tim e, Lee Atwood was 'Dutch's' right -ha nd man and chief engineer fo r the co mpa ny. Atwood, a co mpo ne n t designer an d mat hematical ana lyst at Douglas, was hi red away by ' Dutch' and was responsible for t he NA-16. In t he 19905, Atwood would clai m he came up with t he idea of placing the radiato r o n the new figh ter design behind th e pilot. However, Atwood 's claim was rebu ffed by several othe r su rviving NAA employees fro m th e time period , w ho stated th at t he location was the obv iou s cho ice.

This view of th e prototype N A~7 3 X shows both the moveable fro nt sco o p and the rear duct in the full dow n position . thus incre asing air flow. O t he r points of inter est include the fact that NAA, for so me obscure reas o n, rat he r cru dely airbrushed the original negative to eliminat e the civil regist ration on the rudd er. Also. a black anti-glare pane l has been added ahead of the wind scr een

T H E PROTOTY PE

9

By placing the rad iat or to the rear, a modest increase in thrust could be achieved hy taki ng in co ld air wh ich wou ld rapi dly expa nd and reduce in ve locity before travelling th roug h the rad iato r. This led to an efficie nt heat excha nge whic h created energy t h at move d through a n arr ow duct, exi ting th rough a movea ble duct. Th us, it was esti ma ted th at aroun d 90 per cen t of the coo ling syste m dra g would be elimi nated by t he efficie nt thru st of t he exi t ing air. In h is new position at NAA, Schmued worke d o n va rious pro jects includi ng t he B-25 bomber and NA-3S p rim ary tra iner, but he also kept wor king on h is own perso na l concept of an ' idea l' fighter. As in t erest fro m the Briti sh Pur chasi n g Com missio n in creased in h avin g NAA lice nse-b uild P-40s, a proposal was presen ted to the 'Brits' on the new figh ter. To give an in di cation of how even ts progressed durin g th is t ryin g ti m e pe riod, the Brit ish liked wha t th ey saw in t heir April 1940 meeting with Atwood a nd issued an orde r for 320 exam ples of t he n ew figh te r (see ch apter two for co n tr actua l de ta ils) 'Dutch' placed Schmucd in cha rge of the pro ject, but th e British also pu t in a req u irement that NAA purchase wind tu nne l da ta from Curtiss on thei r XP-46 (an 'im p roved' versio n of

10

This detail view of t he N A ~ 7 3 X shows t he beautifully streaml ined cow ling which covere d t he Allison v, r 7 10 - t he for me r was handbuilt by NAA's meta l sho p and neat ly hou sed t he e ngine installatio n designed by Art C heste r

P-S l MUSTAN G -,

t he p_.JO design , a nd o ne of th e ugliest aircraft eve r bu ilt ), Curtiss made a quick $50,000 profit from th e sa le an d Atw oo d wen t to Bu ffa lo, New York, to co llect t he pap er s a nd dat a. In correspo nde nce wit h Sir He n ry Self, Atwood wou ld writ e o n 1 May 1940, ' \ Ve have reac hed a n ext re me ly sat isfactory ag reement wit h the Cu rtiss Aeropl a ne Co m pa ny o f Buffa lo whereby th ey are fu rn ishi ng to us dat a cove ring a co m p rehe ns ive series of wind tunn el, cooling a nd performance tests of a sim ilar a irplane, wh ich dat a will assist us in the d esign a nd manufacture of th ese airp lanes'. Ch ief aerodynam icist Ed Horkey ex a m ine d th e dat a and fou nd it Virtua lly useless. Sch m ued wo u ld later claim he neve r eve n saw th e Cu rt iss dat a. On 10 April 1940, t he Brit ish signed t he go-a he ad lett er for the NA-73X pro ject (' 73' for th e NAA model nu mber, ' X' for experimen tal), whil e th e forma l co nt ract was signe d on 23 May. The sma ll NAA eng ineering depar t men t issued d rawings to the fabricatio n sh o ps in a never-endin g st rea m th at in cluded 16hour wor k days, seve n days a wee k. 'D ut ch ' a nd hi s te am we re aiming for a delivery date of a co m ple te airf ram e in Janua ry 1941. Howeve r, th e NA-73X was rolled o ut of the h angar in 117 da ys - alt houg h in complet e in so me det ails an d sitti ng on t yres and wheels grabbed fro m th e Ha rvard production line (NAA would record that they had ex pen de d 78,000 man h our s en gineering the proto type). Also, the eng ine h ad n ot bee n de live red from Allison a nd it wo u ld be another 20 days before th e V- 12 arrived to be mat ed to t he air fram e. Th e firewall fo rwa rd powerplant desig n ins ta llatio n for th e aircra ft h ad bee n en t rusted to Art Chester, a we ll-known race pilot and buddy of 'D utch 's' (and who wou ld go on to figure in other aspe cts of the typ e's prod uct io n h isto ry), who d id a n ex ceptio na l job in stallin g th e powerplan t in a neat pac kage wit h a closely-fitted co wling. Allison eng ineers had rated the V-I710 at 1100 ho rsepower, but had fixed th e criti cal alt it ude at 11/ )00 ft, and here

Magnificently co nst r ucted from different type s of wood, a mod el o f the NA-73 X is seen in the wi nd tu nnel at the California Inst itu te of Technol ogy in Pasadena

THE PROTO TYPE

II

lay th e in here nt weakness of th e eng ine. Th is crit ical altitude figure meant th at th e perform an ce of th e fight er would sta rt to fall off at any altitude over 11,000 ft, th us giving a critical advantage to ene my figh ters wit h a higher altitud e rating o n thei r powerp lants. NAA h ired freela nce test pilot Van ce Breese - a co lo urfu l and often o utspo ken perso na lity - to do th e first tes t flight. At t he time, several freelance pilot s vied fo r test wo rk, and the pay was o ften very lucrative. Th e mo rn ing of 26 October 1940 fou nd t he NA-73X parked on th e ramp wit h Breese in the coc kpit , go ing ove r a mental check list. Hitt ing th e starter, t he Cur tiss-huilt propeller jerked a few times an d t he Alliso n burst int o full staccato life, with just a hint of smo ke d issipat ing from the exhaust stacks. The powerplan t had been run up by mechanics ear lier in the mornin g. S-turning, Breese began to taxy th e pro to type - the lo ng nose obscu red forward visio n, whic h mad e Sct ur ni ng mandator y. Po in ting th e nose int o th e wind and stand ing o n th e brakes, Breese gave t he Allison a th orough run -up . On ce sati sfied, the pilot took th e acti ve and moved t he th rott le sma rtly forward. After ro llin g a h un d red feet, he brou gh t t he engine up to full power and pointed the nose do wn the cen t re line o f th e run way, shovi ng in right rudder to cou nteract the torq ue. The NA-73X was quic kly airborne but the first fligh t was a rather sedate affair, Breese keep ing wit hin glidi ng d istance of Min es fi eld. Afte r flying for abo ut 20 mi n ut es, he found t he gleam ing that t he ai rcraft excee ded initia l perfor man ce estimates . Throttlin g back, he b rought th e NA-73X in for a smoot h landing - three more test fligh ts were made by Breese before he went o n to other project s. NAA was fortun at e in hav ing access to an excellent wind tu n nel facilit y at t he California Institu te of Technology in nearby Pasadena . Conc eived in th e 1920s by Th eod ore vo n Karm an (co nsidered by many to be the fat he r of ae rona ut ics), t he tu nnel was used by NAA to prove man y o f its design advances. So imp ort an t was the tu n ne l to th e later war effort t ha t armed gua rds were positioned aro u nd th e buildi ng in wh ich th e tunnel was housed . Cal Tech scien tists and eng ineers worked aro und -the-clock shifts. Ju st befo re t he wa r began, th e tunn el was o fficially inspected by Cha rles A I.ind bergh , who was o n special assign me n t for th e govern me nt to inspect th e nation's ae rona utica l research capabilities . Th e wind tunn el was bu ilt with a gran t from th e Dan iel Guggen he im Fund, which also made possible th e fou nd ing o f th e Guggen heim Aero na utical Labora tory (GALell') and an en tire acad emi c bu ild ing in whi ch to hou se th e facility. NAA used t his facilit y t hro ugho ut t he war. Paul Balfou r (comme rcial pilot ce rti ficate n umber 12596) was hired by NAA and assigne d th e post o f chief test pilot fo r th e NA-73X. Befor e his death in th e early 19 70s, Breese made th e com men t th at he had het mo ney with NAA officials th at Balfou r would cra sh the aircraft on his first fligh t. Breese wo n. 12

The st ricken NA-73 X is seen in a bea n fie ld just 150 yards west of Mines Field sho rt ly afte r its cras h landing o n 20 November 1940. Test pilot Paul Balfour managed t o scramble to safety via the canopy's side window.This view show s th e aircraft's gen erou s flap ar ea to advantage, along with th e o pening for t he air scoop. It is also interesting t o no te th at t he C urt iss propeller is not in sight, having been ripped away from th e engine and tak ing t he nose gear case alo ng in the process. Note that t he both wing t ips have been ben t o ut of shape du ring t he accident - de cade s late r. t hese same o ute r wing panels wo uld be rem oved (since the y were not ess ent ial st ructu res ) for a new ge nerat ion of Mustan g pylo n racers

P-SI MUSTANG .,

One t he mo rn ing of 20 Novem ber 194 I, t he gro un dcrew prepared the NA-73X for Balfo ur 's first night . Wit h t he Allison already ru n n ing, Balfour climbed in to the cockpit an d took off at approx ima te ly 071 O. The pu rpose of the fligh t was to undertake several speed ru ns over tim ing positi ons set up o n t he field. Mechan ic Olaf T Anderson later stated th at t he eng ine ha d run fine on th e grou nd an d, 'at abou t 0540, 1 warme d the engine u p as is the usual proce du re befo re the flight. Oil an d Prestone temperat ures were no rmal (oil 65°C, Prestone 95°C). Oil pressu re and fuel p ressu re were norma l at I ROO to 2000 rp m. Oil pressure was 80 Ib an d fuel 13 lb. The eng ine was ru n fo r five minutes and th en sh ut down. When I sta rte d t he eng ine for Mr Balfou r before take-off, it was a littl e hard to start (t he Alliso n represen ta tive said t hei r eng ines have a ten dency to do such)' . As Balfou r pulled up (after abou t 12 mi n ut es flying time), th e eng ine stop ped completel y. Checking t he inst ru men ts, nothi ng seemed amis s. However, exec uti ng a wide swee ping tu rn ca used t he NA· 73X to lose altitud e and Balfour q uickly realised t hat he was not go ing to make t he ru nway. Du ring t he last portion of th e tu rn , he dumped lan ding gear an d flaps as he directed th e st ricken prototype to ward a ploughed field just west of Lincol n Boulevard. Th e now-glider whistl ed down in a correct lan d ing atti tude, bu t as soon as t he tyres touche d t he soft soil (at approx imately 0 72 :~ ) , the NA-73X vio lent ly flipped over. The built-u p st ruct ure behi nd th e pilot saved Balfou r from being cru sh ed , and th e pilot scramb led for safety from the moveable side window. At the time o f the accid en t t he prototy pe had accu mulated just three hours and twen ty min utes o f flying time (Balfour had logged 2298.40 hours of solo time at th is point). The Civil Aeronautics Autho rity Air Safety Board listed d ama ge to the aircraft as 'e ngi ne hous ing broken, bot h wing tips dam aged, ta il su rfaces da maged , to p of fuselage dam aged, and ot he r miscellaneous damage' .

THE PROT OT YPE

13

The NA-73X is lifted from th e bean fie ld by crane. No te the smashed cowling and vertical fin. and how th e cock pit area escaped damage. co urte sy of the extremely robu st ro ll-ove r stru cture be hind t he pilot

Investigatio n of the cras h revealed that th e Alliso n had ru n d ry whe n th e selected tan k had been allowed to be ru n out of fuel. Nort h American and th e British bot h agreed t ha t, in sp ite o f the crash, th ey had a win ning aircraft and th e accide nt was no way the fault of th e design. Some aviati on h isto rian s have reco rded th at the proto type was scrap ped after the accide n t bu t this was not the case. Actu ally, the p rototype was ca refully lifted out of th e bean field by cran e and tr anspo rted back to th e NAA factor y, wher e it was st rip ped apa rt and rebu ilt in a very short time. R C ' Bob' Ch ilto n was hired as chief test pilot to replace t he u n fo rtu nat e Balfo ur, and a study of h is log hooks indica tes th at he fiew t he rebuilt NA-73X o n 3 April 1941 for a o ne- ho u r fam iliarisation flight fro m Mines Field. Chilton also reca lled t hat th e NA-73X hact made bet ween five to six fligh ts wit h another pilot at the co ntrols im med iately afte r its rebu ild . Chilto n wen t on to mak e at least a dozen mo re fligh ts wit h t he aircra ft. He later remar ked , 'the NA-73X was a clean flying aircraft with no bad vices. It was q uite pleasant in t he air an d handl ed very similar to th e lat er produ ction art icles '. Ch ilto n had accrued co ns ider able fight er expe rience in th e Army Air Co rps before co m ing to NAA, flyin g th e Roeing P-12 14

P-SI MU STANG

and P-26, Curtiss P-36 and ot he r fighter types. His expertise in th e fighter field ena bled the enginee rs to incorporate changes tha t would be be ne ficial to t he comba t pilot. 'I recall tha t the NA-73X was just pushed to the side after it had been retired from its last flight' , sta te d Ch ilto n. 'It probably end ed up on t he company's jun k pile, but I do not reca ll seeing it there. The NA-73X was a very att ractive machi ne and its alumi num skin glowed with constan t wax ing hy George Mounta in Bear Lane, an Ame rican Indi an whose du ty was to keep the airframe as clean as possible to pick up th ose few vita l miles per hou r.' With t he first aircraft coming off the prod uction line, NAA and the British decided to use these airfra mes for cont in ued testi ng. 'Th e "o ld" NA-73X was no lo nge r represen tative of th e design' , state d Chilton. 'We had orders on o ur han ds for h undreds of new fighte rs and t he NA-73X had served its purpose. It had esta blished t he tre nd for what I believe was the finest propeller-d riven fighter ever built by any cou ntry.' Recen t resea rch indicates that the NA-73X, stripped of useable co mponents, may have bee n donated to a local t rad e schoo l.

Following the arrival of this offici al Brit ish Purchasing Co mmission co mmun ique at NA A o n 12 Decem be r 1940 , t he NA-73 be came known as t he Mustan g

EXPORT OFFIC E BRITISH PURCHASING COMM ISSION DECEMBER 9, 1940 IN REPLY PLEASE QUOTE BACfCIA250 (FSC) NORTH AMERICAN AVIATION, IN C ,I N GLEW O O D, CALIFORN IA CONTRACT A2S0 FOR THE SUPPLY O F NA-73 A IRPLANES AND SPARES LETTER O F AMENDMENT N O 13

GENTLEMEN: WE ARE TO INFORM YOU THAT THE ABOVE MENTIONED AEROPLANES HAVE BEEN GIVEN THE OFFICIAL DESIGNATION 'M USTANG', AND THIS NAME SHALL BE USED IN ALL CORRESPONDENCE.. PLEASE RETURN TO US TH E THREE ATTACHED COPIES OF THIS LETTER DULY SIGNED BY AN AUTHORISED OFFICER OF YOUR COMPANY. VERYTRULYYOURS, HIS MAJESTY'S GOVERNMENT IN THE UNITED KINGDOM BY BRITISH PURCHASING COMMISSION BY (SIGNED) R. F. PAYNE FOR AND ON BEHALF OF THE DIRECTOR GENERAL

ACCEPTED: DATE DEC 12, 1940 SUPPLIER: NO RTH AMERICA N AVIATION,INC BY: (SIGNED) NOBLE SHROPSHIRE TITLE: CONTRACT ADM INISTRATOR

T H E PROTOTYPE

15

LAMINAR FLOW ne of the main factors in making the P-51 a high-pe rfo rmance fighte r was the deve lopment and produ ct ion of a wing inco r po rating a laminar airfoil.The co ncept was o riginally devel-

O

oped by the Natio nalAdvisory Committee fo r Aer on autics ' A C Robi nson. wh o did a paper o n the subject, and later supplied data and re sear ch notes on laminar airfoils.Although the laminar concept had been known for quite so me time, it had rar ely been applie d to an act ual airc raft. Basically. a laminar flow featured a symmet rical air foil tha t ut ilised the same curvature o n lower and upper surfaces.The lead ing edge was kept as thin as po ssible w hile the airfoil's greatest th ickness was placed as far back as po ssible . In prac tice , this wo uld kee p t he bou ndary laye r air flow adhe ring to the wing surface further aft of the leading edge th an any oth er type of airfoil. Em ploying a normal airfoi l wo uld mean th at the bo undar y laye r broke up much earlier on th e wing surface , causing t urbulenc e result ing in dr ag, and a drop performan ce. Unfo rtu nate ly, the few w ings th at had bee n construct ed to take advantage of the laminar principle w here hand-built, and t he surfaces had been highly finished to prom ot e a t rue laminar flow. Such hand-finishing wou ld be impractica l on a production -tine fight er. so NAA engineers came up w ith a method of filli ng and san ding the lea ding edge of the wing to insure laminar flow - 'lam inat ing' layers of air over and unde r th e w ing t o insure a pe rfect an d smooth air flow.

16

P- 5 1 MUSTAN G

With such a radi cal airfo il, and a new method o f production, NAA made sure that th ey had an 'escape ro ut e' should the laminar flow wing not work. de signing a more co nve nt ional flying surface th at coul d quickly be put into pro duc t ion should the former unit prov e to be a failure . Fo rt unat ely, the laminar flow experimen t (t est ed in th e wind tu nnel at th e Ca lifornia Inst itu t e of Techn olog y in Pasade na) pr oved wo rkab le in mass pr o duction, and th e final airfo il had a thi ckness ratio of 15. 1 pe r ce nt at the wing root at 39 per cent of the chord. Tip ratio was I 1.4 pe r cent at th e 50 per cent cho rd line, with th e maximum thickn ess area at 40 pe r ce nt from th e w ing's leading edge .This resulted in a small negative pressure gra dient ove r th e first 50 t o 60 pe r cent of the wing. At the factory. the wings were prim ered an d finished with airfo il smoot her. Th e first 40 per cent of th e wing cho rd was shot w it h o ne co at of zinc chromate prime r.This was then fo llowed by en ough co ats of Acme Gray Surface r No 53N 5 to cover all irregularities. Skin butt joints were then filled w ith Acme Red Vellunite glazing putty No 58485.The ent ire area was then sanded down and sprayed wit h o ne coat o f camo uflage e namel (when camouflage was dele ted, the forward port ion o f t he w ing was sprayed silve r) .This was a simple and quick way to create a ne arly perfect laminar flow surface, but one has to wo nde r just w hat effect all th o se size 12 G I boots (wo rn by bo th air- an d grou ndcrew) in th e field had o n the carefully-applied laminar flow finish!

CHAPTER

rn BUNDLES FOR BRITAIN

AS MENTIO NED IN TH E p revio us cha pte r, the British Pu rcha sing Co mm ission was ext remely plea sed with the aircraft created by Nort h American's design team, but th eir in itial o rder received a cod icil from th e US govern ment. In return for letting Britain order th e new figh ter, it wan ted two early p roduction aircraft made available to the Un ited States Arm y Air Co rps at absol utely no cost. The British enjoyed putt in g names to th eir ai rcraft designs (as evide nced by t he Spitfire, Hurri can e and Blenheim ) and, fo r a whil e, th e name 'Apac he' was co nsidere d sin ce i t represen ted t he wildness of the American west. However, 'M ustang' was finally chosen for t he figh ter, call ing to m ind th e sma ll, hardy and swift hor se of t he Ame rican plains that had descen ded from Spa nish stock. It wo uld tu rn out to be a partic ularly appropriate na me . In ligh t o f th e British (and American ) in terest in th e new figh ter, it was just as well th at NAA had esta blished an efficien t pro duc tio n lin e p rio r to un veil ing th e NA-73 - a fact t hat has been main ly ove rloo ked when an alysing the suc cess of t he design . Besides cranki ng out a few 0 -47 ob servat ion aircraft, the com pan y's main manufactur ing thrust had been with t he 8T9(fexan /Harvard series o f t raine rs. Co pying th e same efficient style o f train er prod uct io n, a line was set up in rapidly co nstru cted new buildi ngs at Mines Field whi ch wou ld easily acco mmodate the flow of sub-assemblie s that were eve nt ually tu rn ed into complete fighters . In com par ison, t he Supe rma rine Spit fire was a very co mplex fight er to buil d, an d was not reall y suited for th e style of mass-produ ctio n techn iqu es env isioned by Hen ry Fo rd - the creator of really efficie nt mass-production . Un like t he Spitfi re, th e Mustang 'went to geth er' almost like a large met al mo del aircra ft kit, making it ideall y su ited for cons t ructio n in very large num bers. 'Dutc h' Kinde lbcrge r kep t p ressu ring for an adv anced production lin e, apparently realising th at the com ing war, and t he Army's gro win g interest, wou ld lead to man y mo re o rders. Th e year 1941 was an ext remely bus y o ne for NAA. Position vacan t ads in so ut her n Ca liforn ia newspa per s b rough t in hordes of wo rkers fro m all acro ss the natio n - men looki ng for stead y wor k to escape the effects of th e Great Dep ression . BUND LES FOR BRITAIN

17

NAA was hiring by t he hundred s as th e initial orde r fo r t he Mustang Mk I amounted to 320 aircr aft (rapidly growing to 620 aircraft), and skilled wo rkers were at a premium. Typica l for th e time period, th e price of the aircraft would exclude the engine, armament, radi o s etc. The RAF was gett ing th e basic airframe, and although everyt hing else would he added on at th e NAA factory, th e British gove rn men t was resp on sible for purchasing and supplying th e remain ing items. As a co nt ract stipulatio n, t he basic airframe price was not to exceed S40 ,OOO. The prem ier Mustang Mk I (RA F serial AG34S) made its first fligh t from Mines Field , wit h Lou is Wait at th e co n tro ls, o n 23 Ap ril 1941. The seco nd aircraft - AG346 - was di sassem bled and fitt ed in a sto ut woo de n crate for th e hazard o us ocean voyage, arrivin g safely at Liverpool on 24 Octo be r 1941. The Mustan g was ta ken to Speke Aerodro me for ini tia l flight testing, whic h confi rmed the result s reco rded wit h the NA-73X and AG34S. Many Brit ish pilots were assigned to fly AG346, and t hey fou nd the new fighter satisfacto ry in its designed role. As reco rded in th e previous chapter, part o f t he Mu stang's excellen t performan ce was due to the clever design of the cooling system, although th e ma jor co n tributo r was th e aircr aft 's laminar flow win g. Briefly explained, this is a t ype of airflow over an ai rfoil in which the air passes over the su rface in

18

P-S I MUSTANG

LEFT This wonderful high-angle view of Mustang Mk I AG348 (the fourth prod uction aircraft) illustrates the very simple layout of the fighter,and also shows th e angular wingtips to advantage . Most fighter s pro duced pre vio us to the Mustang had elongated curved wlngtips which we re believed, incorrectly,t o cut do wn on drag.Also, the angular wingtips were much easier in build in mass quantity.The photograph also shows the ea rly short air scoop for the Alliso n's car buretto r;This arrangement caused, at different

air speed s and angles of attack, a non- unifo rm flow of air to t he engine which re sulted in surging. This pro blem was so lved by slightly raising the inlet and extending the lip close r to the pro pe ller.The se early Mustangs were camo uflaged in Ear t h and G reen upper su rfaces and Sky Type S unde rside s. Uppe r wing roundels were red and blue while t hose on the fuselage sides were, from o utside in, yellow, blue , white and re d. Finally, the unde rwing ro undels were blue, whit e and re d

A BOVE 'Dutch' Kinde lberger is seen in t he cockpit (minus the comfort of a sea t) of a Musta ng Mk I whilst showing the aircraft off to a visiting British official.As can be seen, the fuse lage was in a movable jig, and various part s we re affixed t o the airframe (like t he box co ntaining t he Parker engine primer o n th e firewall) along wit h a list of sho rta ges for the particular airframe

BU ND LES FOR BRIT A IN

19

Although it looks a bit crude by today's standards, this airframe is being thoroughly studied as more and more lead weights are added to the aircraft to test its ultimate structural integrity. A tempo rary wooden partition encloses t he aircraft from rest of the factory as such testing cou ld be hazardous since there was always

20

P-S I MU STANG

the chance of a catastrophic structural failure, which could send bits of metal flying about at high velocity. Several other Mustang books have wrongly identified this aircraft as the NA·73X. It was an incomplete airframe (often referred to in testing documents as XX. 73) t hat was tested to dest ruction to provide accu-

rate data on the airframe's strength and then scrapped after the trials had been completed. The testing progressed in a very logical manner, finally culminating with crucial wing strength trials the fly ing surface failed at 105 per cent of its design load.This highly-de tailed photograph was take n on 16 January 194 1

.. ......,. ,.

""

A smiling 'Dutc h' Kinde lberger and a so me what dou r Sir Hugh Do wding at t he NAA plant o n 10 Febru ary 1941. Dowding, o n an inspection to ur, is ho lding a prese nta t ion mo del of t he Musta ng Mk I

Dem and fo r t he Mustang Mk I was so grea t t hat early examples we re rapidly crate d and shippe d to Britain. As t his pho tograp h shows , t he packing cra te itse lf was a bit of a work of art, being designed to ho ld all of t he aircra ft's com po ne nts. W hile o ne workman affixes t he vertical fin to the right side of th e crate wall, ano t he r slides in the horizo ntal sta biliser. No te th e pilot's seat fixed t o t he floor of th e crate. The wings in the backgro und are for a Harvard BUNDLES FO R BRIT AIN

21

Left side of a Musta ng Mk l's cockpit, ill ust rating the tr im co nt rols for the ailerons, rudd er and elevator. The landing gear handle is at the bottom of the side co nso le. while the co mpact throttle and propeller controls are co nveniently placed for the pilot's left hand

22

P-SI MUSTANG

smo ot h layers with a minimum of turbu lence. With most airfoils there is a layer of ai r ad jacen t to th e su rface tha t flows in a rando m fash ion , sometimes eve n reversing its d irection of flow. Thi s is th e boundary layer. The laminar flow airfoil is designed in suc h a way t ha t th e bounda ry layer has a mi nim u m th ickness, and nearl y all t he air flows in smooth layers . Lam inar flow o f th e air decreases th e dr ag produced by th e ai rfoil. The laminar flow wing on th e Mustang was the first time that suc h an airfoil had been employed o n a prod uction m ilitar y aircraft , th e design of th e airfoil itself being based up on Russell Robin so n's rep ort s filed with the Nat iona l Advi sory Committe e for Aeronautics (NACA). Rob in son (an ae rody na miclst with NACA) had cond ucted succe ssful wind t un nel expe rime nts wit h th is new gene ration of low dr ag airfoils, and NAA aerody nam icist Ed Horkey and hi s crew laboured for weeks to adopt th is data to the new fighter design. Since time was a factor to be recko ne d wit h, Kinde lberger issued an order to Edgar Schmued th at his team mu st be read y to design a co nve n tio nal wing wit hi n 30 da ys in case th e lam ina r flow concept d id no t

work out (in fact all th e data for t his 'seco nd' wing was unear th ed in 199 7 during resea rch in t he Caltech files). Ed Horkey tested his pre lim inary wing in th e wind tunn el at t he Califo rn ia Institute of Tech no logy but foun d th at th e u nit had an unpl easant stall char acte ristic th at was not acce ptab le to Horkey and would certainly be frowned u pon by t he Briti sh . When a modi fied wing sectio n only sligh tly im proved t he problem, Hork ey suspected t ha t part nf the pro blem lay in t he tigh t confines o f t he Ca ltec h tu nn el, so he shipped t he woo de n wing section to the so mew ha t larger tu n nel at th e Uni versity of Washingto n via a Un ited Airlines DC-3. Horkey's gamble paid off, and the win g perfo rmed as planned in th e larger tu n nel. Th e Mustan g Mk I, designa te d NA-73, was fitte d wit h fnur .50 cal and four .30 cal mac hine guns. Most Ame rican fight ers were still well behind t heir Europea n coun te rpa rts in th e firepower depart ment, and th is arma men t selection was co nside red quit e pow erful. Power came from t he Alliso n F3R which reached its opti mum power at lower altitud es. Several small modificati ons were made on combat-ready Mustan gs by t he

Right side of th e Mustang Mk I's cockpit, showing th e map and data case , map read ing lamp. ox ygen regulator and panel fo r navigatio n lights. land ing light and pitot heat. The ro und device mou nted o n the can opy structu re is th e Morse co de key.The spade type gr ip favoured by t he British is also shown to advantage. with the firing button t o the left. Cockpit placards warn no t to exceed 505 mph in a dive and no t t o lower flaps at speeds abo ve 170 mph

BUND LES FOR BRITA IN

23

British, including slight changes to th e air duct system and rad iat o r air scoo p. During subse q uent flight t rials, a co mbat-ready Musta ng Mk I was found to be 35 mph faste r below 15,000 ft (3 75 mp h) t han th e sta nda rd Spitfi re Mk V, alth ough at ceilings ahove t his height performanc e rap idly fell away du e to t he design limitations of the Alliso n whic h, lacking an efficien t form of supe rcha rging, was str ictly a low to med ium altitude en gine - unfortu na tely t he air battles over t he Continent were being fough t at higher altitudes, As mor e early model Mustangs arrived in Britain aircraft were assigned to RAF Duxford for air co mbat testing, where th e type co mpared favourabl y wit h t he Spitfire at lowe r alti tudes . Few vices were u near t hed , and British pilots were impressed with t he NAA's creat ion of a logical coc kpit layout wit hi n the con fine d space offered by th e st reamlined fuselag e. Also whi le at Duxford , t he Mu stan g Mk I was tested again st a captured Messerschm itt Bf I09E and, once agai n, had a d istinct edge ove r 24

P-5 1 MUSTAN G

Fine study of Musta ng Mk I AG345 in flight on 19 August '94 1 with test pilot Bob Ch ilton at the cont ro ls.The slimness of the radiator scoo p installation is notewo rthy.Th is aircraft was reta ined for a time at NAA to test vario us improvem ents - as can be seen. the fighte r has been fitted with the raised and extend ed carburettor air scoop. The first gro up of Mk Is (se rialled AG34S th rough AG664) we re built and de livered to Britain between Novembe r 1941 and May I942.AG345 was st ruck off charge on 3 Decem ber 1946

This head -on view of Mustang Mk I AG346 emphasises the aircraft's elegant and slim lines.The position of the arm ament is also displayed to advantage.Two of th e .50 cal weap ons were fitted in th e lower nose cowl and the re maining two .50s on the inboard wing positio n, leaving four .30 cal wea pons to be housed outboard .The lack of visibility for the pilo t in th is three-point positio n sho uld also be noted.This particu lar aircra ft enjoyed a long o perat io nal caree r before being finally being shot down by flak near Gace on 20 August 1944 while serving with No 168 Sqn of the Seco nd Tactical Air Fo rce BELOW

the Luftwaffe figh ter, but it must be no ted t ha t t he Emil was by t hat time no longer in producti on , having been repl aced by newer and more deadl y aircra ft. In view o f th e type's rest ricti on to lower altitudes, th e Briti sh decid ed to co n ti n ue to use th e Spitfire as t he ir stand ard high-perfo rma nce fight er. RAF Fight er Com mand re ject ed th e Mustan g Mk I, and t he aircra ft wa s sen t off to th e new Army Cooperation Co mmand (ACC). The ACC was esta blishe d dur ing 1940 to co-ord in ate air /g round act ivities wit h th e Army - a vita l task t hat was neglected, with disast rou s resu lts, by th e British Expe d itionar y Force in Fran ce. Th e Mustang Mk I was idea l for th e ACe since it was heavily armed, high ly man oeuvrabl e, had a very good ran ge and could really get mo ving at altitudes below 10,000 ft - th e regime which wou ld be most beneficial to the Army. Up until the int rodu ction of the Mustang, the ACC had bee n eq uip ped wit h Westland Lysanders an d Curtiss Tomah awks, neith er of whic h were ideal for fron tline ope ration s over heavil y-defended target s in Occu pied Europ e. It was initially plan ned to eq uip 18 squa dro ns with th e Mustang, but only 16 squad ro ns were eve ntu ally so constit ute d. With 'Dutch 's' co ncept of a high-tech production line ha ving bee n in place fro m the early stages o f th e Mustan g's developm ent, aircraft were rap idly rolling o ut o f th e assem bly hangars to join Texans and new B-25 Mitch ells on th e co mpa ny ramp . Furt her modificat ions were in sto re for t he fight er, however, and 150 Mustan g Mk lAs (NA-91) fitte d wit h four 20 mm can no n in t he win gs were built. Fifty Mk lIs (NA-99) were also supplied to Britain, th ese being USAAC P-5 1As pull ed from th e produ ction lin e. The RAF even tua lly received a total of 69 1 Allison- po wered Mustangs from th eir o riginal co n t racts, th is figure deleting t hose aircra ft lost at sea d uring shipping .

BU N DL ES FO R BRITAIN

25

DOLLARS AND CENTS

'We furt her offer to co nt inue th e manufactu re of the se planes at t he rate of 50 airplanes per mo nt h unt il at least the end of the yea r 1941 , sho uld yo u desire to incorporate and exercise an o pt ion for these additional airplanes prior to 30 April 194 1.

hat did it cost for th e first Musta ngs. what did th e Brit ish and NAA expect from each other and how was th e contract awarded? The following is a lett e r from NM's Lee Atw ood to Sir Hen ry Self of th e Anglo-Fren ch Purchasing Co mm ission.The lett er was dated I May 1940. In today's litigious so ciety, th e lett er appears t o almost be a gentlemen's agreement;

W

'In accordance with o ur understanding. we are proceed ing wit h the design of a single-sea t fighter airp lane, ou r Mo del NA-73, incorporating an Allis on engine and fitted with provi sion s for

equipme nt and arma ment as detail ed mo re completely hereunde r. 'We have reach ed an ext re mely satisfact ory agreement with t he Cu rtiss Aeroplane Company of Buffalo wherein the y are furni shing t o us data covering a comprehens ive series of wind tunn el, cooling, and performance te sts of a similar airplane , which data will ass ist us in the des ign and manufact ure of these airp lanes.We have also rece ived release from th e United States Army for the manufacture and export of the se airplanes and wish to assure you that all ar rangeme nts are entirely satisfactory.

'We are prepared to co nst ruct and deliver to you 320 of the se airplanes before 30 Sept ember 1941, and guarantee t o effect deliveries in accordance wit h the following de livery schedu le:

'We have co nstructed a moc kup and have co mpleted t he initial phase of the detail design and are submitting to you herewith certain data and info rmat io n regard ing th e cha ract eristics of th e airp lane. You will no te tha t we have provided for armor prote ctio n fo r the pilot and a sealing arrangement for the fue l tank s. Pro visions are being made for the installation for four .50 caliber machine guns. two of which are in the fuselage and the o th er two in th e wing. As a no rmal load we are specifying 200 ro unds of ammu nition per .50 caliber gun. but are making additional prov isions for more ammun itio n as a special loa d. Pro vision s are being made for four British Type 303 machine guns with ammunit ion boxes to acco mmo date 500 ro unds of amm unitio n per gun as no rmal load. 'Strictly for com parative purpose s, we are including th e results of a study show ing th e differ en ce in size and performance betwe en t he airp lane offered and o ne which might be offe re d with a minimum armam ent and witho ut protective armor. but is otherw ise the same . It will be no te d that th e high speed in t his condition is 400 mph with a wing area of 190 sq ft. W ith a full co mplement of ar mament and armo r plate prote ct ion front and rea r, t he weight is increased from 6450 Ib to 7765 Ib and th e wing area is incr ease d from

1941 FEB

MA R

APR

MA Y

JUN E

JU LY

AU G

SEP

Airplanes

5

20

40

50

50

53

51

50

Spares

3

5

5

5

5

10

15

15

JAN

(equivalent ale)

26

P· 5 I MU STAN G

OCT

NOV

t 90 sq ft to 230 sq ft in ord er to maintain the same landing spee d.The resulting pe rformance is materially redu ced and high speed is 384 mph under the same condition s.

'The speeds quoted above are based on a power of 1030 hp at 16.000 ft altit ude. using 90 octa ne fuel.Since we do not have precise and final information on the powe r rating of the engines to be furnished for th ese airplanes. this rating is still somew hat of an estimate.We believe the AngloFrench Co mmission has. or will shortly have, accurate information on this matter.When we receive the exact figu res. the perfo rmance guarantees will be arithmetically adjusted accordi ngly.

We have made a careful estimate of th e price . including sufficient st ructural tests to guara ntee the st ruct ural integrity of all parts, wind tunnel testing and flight testing.We have include d a pr ice breakdown. separating and pricing all items of equ ipment to be installed and supposedly furnished by us.We have not co nside red the price of engine. propeller. radio. oxygen. machine guns or ot her ite ms of armame nt or military equipment. and it is assumed that the se items will be furnished to us free of charge for installatio n in the airplanes.The price summary for airplanes, ex clusive of crating o r tran sportation. but cove ring all other charges is as follows:

$ 983.9 5 A) Power-plant. eng ine accessorie s 'The genera l provisions for armament have been discussed B) Inst r ume nt s 1787 .35 with Air Co mmodo re Baker and C ) El ec tri cal Equi pmen t 890.75 MI:Thom as and it is believed D ) Miscellaneous Equipme nt 52 8.40 that the arrangement offered is E) Rad io Equip me nt Cu st o me r fu r nished the most pract ical possible at this time, co nsiste nt with the C us tomer fu rn ishe d F) Ar mam e nt general instructions we have received. It is possible to To ta l equ ipm e nt to be increase the fire power 4190.45 furnished by Contr acto r th rough the installation of 33,400.00 Base airplane additional guns if abso lutely necessary,but the perform ance 37,590.45 Total per Airplane will suffer a proportionate loss. We feel there will be no difficulty 12,028,944.00 Total for 320 Airplanes in making any changes o r Spa re parts (20%) 2,405 ,788.80 modifications which you may feel 2 16,000 .00 Crating per a ir plane $6 75. to tal are essential or desirable, and are prepared to co-o perate wit h 96,2 3 1.35 Crating for spare pa rt s (4%) your technical staff to the fullest exte nt.We do feel. however. that 14.746,964,35 To tal Contract Am ount the design as presented is close to an optimum co ndition. all things con sider ed. Details of equipment and installation are yet to be covered. 'Wi thin 60 days after the contract has been executed we will furnish a complete percentage but our previous experience wit h Harvard aircraft, which incorp orate much British breakd own and a rec omm ended list of spare parts to approxi mate 20% of the co ntrac t price s of th e equipment. leads us to be lieve that we will have airplanes. Spares will be delivered in acco rdance no difficulty whatever in ar riving at satisfactory with the delivery schedule attached hereto, agree ments in all these matte rs.

BUNDLES FOR BRITAIN

27

provided a spare parts list is approved and agreed upo n within 60 days after submissio n of such a pro posed list by us. 'We are prepared t o proceed immediately upo n rec eipt of a letter from you acce pt ing th is pro posal and receipt of down-payme nt. We des ire a down-payment of 10% of th e co nt ract amo unt upon approval of th is pro posal and a subsequent monthly payment of 2.5% of the contract am ount each month until 25% of th e contract has been paid. Details of final payments and acceptance will be as mutually agreed upon and in general accordance with our previous contracts with the British Government.We feel t here will be no difficulty in t he prepa ratio n of th e final co nt ract at your convenience inasmuch as we have rea ched agreemen ts with you r staff concern ing all pr incipal po ints invo lved in a co ntract of th is type . 'The price s quo te d above are inten ded t o include all normal and reasonable mod ifications and

changes which yo u may req uire. prov ide d that such change s are agree d upo n w it hin t hree mo nt hs of th e date of th e agreement and provide d th e re is no co nside rable addit iona l ex pense to us as might be invo lved in th e pur chase of additional mate rial or equ ipment. Cha nges init iated after th is time may invo lve a de lay in delivery or a cost increase. 'May we request that you give this matter your ea rly attention as we are prepared to proceed on rece ipt of a letter of approval from you and re ceipt of down -payment as reque ste d above .We will con sider the date of receip t of this payment as the date of the contract. 'If th e re are any matters no t prope rly covered in this lette r o r th e enclo sed data and it is necessary to withho ld the lette r unti l such matters are clarified . we will grea tly appreciate it if you will noti fy us of th ese matt ers by telegram or tele pho ne at o ur ex pe nse in o rder that there will be no delay.'

Brit ish Purchasing Co mm ission acce pta nce pilots C hris C larkso n (cent re) and Battl e of Britain ace Michae l 'Red Knight ' C ross ley (right) po se with LA Coste llo. th e reside nt t echn ical officer with the Brit ish Air Comm ission OP POS ITE TOP

28

P-5 1 MUSTANG

RIGHT They had good reaso n to cover t he ir ea rs - thes e NAA wo rke rs are subjec te d to th e rigours of a canno n t est o n a Mk IA which was fitte d with fou r 20 mm weapon s in place of the machine guns.The aircra ft has been jacked up into flying att itu de and a batte ry cart pro vides power via a plug on th e right side of t he fuselage. To have t he laminar flow airfo il work most effect ively. the paint and skin co ndit io n of th e wing was supposed to have been mainta ined without scratches o r marring - so meth ing not evident on this airc raft!

BUNDLE S FOR BRITA IN

29

CHAPTER

C[]

PONY SO LD IERS

WHE N AMERICA N GO VERNME NT APPROVAL was given to allow Nort h Am erican and the Brit ish to proceed w it h t h e d evelopmen t of t he NA-73, one o f the co n d itions th e fo rmer in sisted upo n was that the fourth and ten t h produ ction a ircraf t be h and ed over to the Army Air Corps. An Aut h o rity fo r Purchase document (n umber 16526 5) was issued o n 24 j u ly 1940 and ca lled for t he delivery of th e t wo aircraft wit h t he AAC designation of Xlt-S1. On 20 Sep tember of t h at same yea r, an official contract was approved by th e Assista n t Secretary of War. Th e two prot otypes were built in accorda nce with t he British Model Spec ification, a lt ho ug h certa in m odi ficat ion s were also mad e to accommod at e sta n dard Army eq uipmen t. As wit h t he British aircraft , th e wings consisted of two pane ls bol ted together at t h e centre p lane of the fuse lage . The mai n and rea r spars were of flan ged aluminum alloy sheet const ructio n, wit h the flap and aile ron hi nge sup ports m o un ted on t he rear sp ar. Th e rem ain in g str ucture co nsisted of ex t ru de d stringe rs and p ressed ribs, onto wh ich a skin covering o f al umi num coat ed alum in um alloy was rivett ed . Space between t he m ain and rear spa rs o n each side of the centreline was arranged t o h old the fuel cells, a struc tural do or being provid ed in the under su rface of eac h win g sectio n to facilitate t hei r installation an d removal. Th e aileron s we re of th e sealed balance type. Th e fuse lage constr uction at t h e cockpit sectio n co n sisted of two curved side panels, four longeron s (two o n eac h side of the cockpit) formi n g its st ructu re togethe r with th e outer skin , wh ich was reinforced by ver tica l fram es. Aft of the coc kp it, the longeron s extended into a sem i-monocou pe st ruct ure rein fo rced by vertical frames. All skin and fra mes we re aluminum coated alu mi n um alloy. Th e fuselage was d ivided into t hree sectio ns - t he eng ine sect io n , t h e m ain section and th e tail sectio n . All sections were de tachable, an d attac hed with bolts. Th e tail u n it was a full-cant ileve r st ruc tu re wit h a sem im onocoupe fin an d stabiliser, the latter being constru cte d as on e unit wit h deta chabl e t ip s. Th e full-cant ileve r m et al-cov ered st ruc ture consisted of tw o spa rs, alum inu m alloy ribs an d extrude d st rin gers. 30

P-5 1 M U S,~T,:;: A.:;: N~ G~_ _

The elevators was mad e up o f two sections, each int erchangeab le with th e o the r, an d were of fabric-covered aluminum alloy co nst ru ction. Th e st ructure co ns isted of a front spar, a short int ercosta l rear spa r, flan ged ribs and metal leading and t railing edge sections. Roth elevato rs were static balan ced and eq uipped with tr im tabs, which were con tro llab le from the cockpit for longitudi nal tri mm ing o f th e aircraft und er all flight cond itions. The vertica l sta biliser was a full -cantilever semi-monocoque stru cture co nsisting o f a for ward and rear spar, flan ged ribs and ext rude d stringe rs. Th e rud der was sim ilar in st ruc tu re to the elevato r, being fabri c covered and dyna mic ally balanced . It was also eq uipped wit h a trim tab controllab le from t he cockpit for d irect ional tr im min g o f th e aircraft u nder all flight co ndit ion s. The land ing gear co mp rised two main lan d ing gear assemblies an d a steerable ta il wh eel, all of wh ich were exte nde d and retracted by hyd raulic pressure. They were com pletely encl osed by fairing doors whe n retract ed . The tail whee l was capa ble of swivelling 360 an d was steerable wit h in th e ran ge of the rud der pedal travel. The main land ing gear whee ls were fitte d with hydraulic brak es.

De tailed facto ry view of P-S IAs undergoing final co mpletio n o uts ide th e NAA factory. During this time period the company was rapidly ex panding, and so me of th e final work had to be com plet ed o utside. No te how the aircraft are on jacks. and th at the NA-99 de signation has bee n applied to th e rear fuse lage of each aircr aft, alo ng with th e last two digits of the manufacture r's co nstruct ion numb er.Also note the additional windscreen window

0

PON Y SO LDI ERS

31

Produ ct ion o f th e new figh te r for t he Briti sh rapidl y mo ved forwa rd an d on 20 May 1941 Rob e rt Ch ilto n made t he first XP· 5 1 flight in AAC si n 4 t-03K. Alt ho ug h pro gress wit h the British aircraft was relati vely rap id, th e same co u ld not be said o f the Ame rican Mu stan gs, Th e first XP-S1 arrived at \Vright Field on 24 Augu st wh ile th e seco nd XP-5 1 (sin 4 1-0:19 ) did not get to t ha t loca tio n un til 16 December - the two aircraft had been sch edu led to arr ive in Februar y a nd Ma rch ! Exp a n sion of the America n ai rcraft indust ry to face wha t wo uld a p pa rentl y he a certa in e nt ry in to the war in Europe saw Nort h American issued wit h a co nt ract for ISO ('-S Is o n 7 Ju ly 1941 - well before the two Xl's had been teste d . In a report subm itted on 15 j ul y 1942 regard in g th e XI'-51, Capt \V G I.ogan co m me n ted , 'Except for min or incidental ch a nges , the project progressed at a normal rate . O n 24 Februa ry 1942, an Engineer ing Order was issued to rem ove th e origina l h yd rau lic gun cha rge rs o ut o f bot h airpla nes a nd insta ll in lieu th ereo f fu lly auto ma tic gu n cha rge r equ ipme nt which was bein g devel oped by th e Bendi x Co rpo ratio n in t he seco nd airpla ne . Th is was done so th at th e n ew c ha rging eq u ip me n t could

32

P-51 MU STANG

Lo o king no t unlike the NA-73X (and often identified as such in reference bo o ks). the first XP-5 1 poses for its portrait on the NAA ramp. USAAC sin 41-038 was rolled ou t of the factory in a highly po lished natura l metal finish (after its RAF paint had been stri pped) wit h the classy red . w hite and blue tail stri pes th at wer e soon to be eliminat ed as th e th reat of war increase d. The milita r y requested that NAC A perform flight test s on the aircraft. and it was duly flown to Langley.Virginia.Test ing commenced on I March 1942. and was finally completed on IS May of the same year.The aircraft LEFT

was flown for an accumulated total of 24 hours while fitted with special instrumentation. including accelerometers. turn meters and a time r. A recording yaw vane was also added on a boom that extended four feet fro m the right wing t ip. whilst an airs peed boom was mou nted fro m th e left wing t ip.The XP-S I created histo r y d ur ing these tri als as it was t he first aircraft t o fea tu re a low dr ag airfoil t o be te sted by NACA During te st ing. a maximum lo ad fact or of 8 G was calcu lated . along with a te rminal velocity of 0.82 Mach

ABOVE This mock-up section of wing was used for testing the 20 mm canno n. Some pilots felt that the increased weight of these weapons decreased the type 's overa ll performance. Note spent cartridges under wing

PO N Y SO LD IERS

33

be flight tested at an ea rly dat e. Sin ce th e delivery in stallati on, it was decid ed th at provision onl y wou ld be made for insta ltat ion of th is eq uipme nt. ' Prelim ina ry flight tesung was co nd ucted o n th e first air plane a t th e co n t ractor 's plant by th e co n t ractor's per son nel and govern ment pilots in accordance with the terms of the co ntract. Co n side rab le t rouhl e was incurred wit h t he Allison engi ne in sta llat io n in th e ea rly stages of th e airplan e's d evelopment. At o ne part icul ar throttle setting, th e engine was found to be ex t remely ro ugh a nd , in o ne instance, the e ngine complet ely cut out resulting in a forced lan di ng in a plo ug hed field . Th is landing was mad e hy th e co n t racto r's pilot without damage to propert y o r personal injury, a lt ho ug h co ns ide rab le damage was do ne to th e air p lane tuuthcr's note: this triers to till' NA-73X, al/d apparently does 1I0t take i1110 account tlu: fact thu! tile accident repotts il1dicatl'd that th e pilot I",d filii olle tank dry ). 'U nde r the terms of the co nt ract, t he Arm}' was SU P POSl>J to receive t he fou rth a nd te n th prod uct io n ar t icles. Th ese airplanes were schedu led for d elive ry in Februar y a nd Ma rch 19-11. The product ion o f th e NA-7J was dela yed both by th e cra sh landing o f the experime n tal m odel and th e dela y of th e eng ines fo r th e British a irplanes . To facilita te th e delivery of th e XI'-S I mod els it was decided to tak e th e fou rt h and tenth articles from th eir place in the asse m bly lin e a nd in stall th e Arm y eng ines in t hem for delive ry to \ Vrigh t Field . This proced ure was followed a nd th e first air p lane was accepted a t th e plan t of th e co n t ractor and flown to Wright Field o n 24 August 194 1, for th e purpose of co nd uct ing o fficial performance test s. ' Upo n arriva l of th e first airplane at \Vright Field , a safety inspection was co nd ucted. Th e ai rp lane was next we ighe d a nd balan ced and a n actual weight a nd ba lance report prepared . Before flight testing co uld be conducted , it was necessar y to in stall backfire scree ns to prevent d amag e to th e airp lan e d ue to 34

P-S I MU STANG

LEFT Weari ng te mporary American markings for flight testing within the United State s. Mustang Mk IA is prepared for its next sortie.The aircraft was finished in Dark Green and Dark Earth upper surfaces with Sky under surfaces . whilst the spinner was in Dark Earth. AM190 went to the Aero plane and Armament Experimental Establishment (A & AEE) at Boscombe Down for further tes ting. before being assigned to No 5 16 Sqn.The aircraft was struck off charge on 31 Octo ber 1945.The Mk l ied directly to the American Mustangs

BELOW Maste r wing jig for th e P·S IA. which allowed for precise construction of the unit. At this point . the main landing gear leg had not been added. but the forward 40 per cent of the wing had been filled and primer ed. Note that the interior is bare metal and devoid of zinc chromate. The completed wing wou ld ho use two 90 gal fuel cells that wo uld weigh 1080 Ib when full

PONY SO LD IERS

35

engine backfi re. Thi s wor k too k co ns ide rably longer th an was an ticipated d ue to th e break ing off of studs. It was also necessary to insta ll new aileron and flap b racket bo lts to co rrect an un satisfactor y co nditio n found by NAA in other airplanes. Th e replace men t parts were fu rnis he d by t he cont racto r and ins ta lled by Army personnel un de r the supervision of the co ntractor 's represe n ta tive . 'Add itio nal fligh t tests were co nducted on th e two airplanes de liven..-d to th e Army. It was during flight testing of th e first Army airplane th at it was d iscovered th at engine d ifficu lties previousl y encou n te red co uld be ove rco me by increasing th e lengt h of t he ram ming air in take scoop . It was on ly after th e co nt racto r co nsider ed th e airplanes to he sat tsfactory th at they were turned ove r to th e Army. ' Prelim inary performance tests were co nd ucted at t he ro ntra ctor 's plant by personnel on t ~ l' co n tracto r's first articl e du ring xtarch 19-11 , Final o fficial perfor man ce flight tests were co nd ucte d at \Vright Field betw een HOcto ber and 22 December 1941 . The reason for th e long pe riod of flight testi ng was du e to t he hig her prio rity of other airplanes to he tested, bad weather 36

P-S I MUSTANG

ABOVE As production at NAA built up. th e Mustang line was mod ified severa l times to accommod ate increased military orders. In th is view. early Mustangs were be ing built alo ng with Har vards for the RAF Early Musta ng fuselages ro ll down a very cr ude production line. the former being mounted o n rou gh wooden dollys fitted with casto rs for easy movement.The ten gallon oil tank has be en se cured to the firewall through th e use of hefty st raps RI GHT

PONY SO LD IERS

37

ABOVE A P·S IA fuse lage is mated to its wing.The aircra ft carries th e co nst ructor's ide ntificatio n number 132 paint ed o n st rategic areas of th e o uter fuselage and inside pane ls.The clipboa rds affi xed to the fuselage are assigned to the particular aircraft and o utline wo rk th at need s to be don e.The squared off tips of the Mustang's fl ying surfaces not on ly ease d produ ction, but also res ulted in re duced turbulence where t hey mat ed with the laminar airflow wing

38

P- 51 MU STAN G

RIGHT Coc kpit of a P-Sl with th e pilot's seat removed. The large handle near t he floor is t he tail whe el lock. No te t he ST IA gun sight. along wit h th e ring-andbead sight

PONY SOLDIERS

39

Installing the SCR-274 command rad io behind the P-51A pilot's positio n.This rad io was th e main co mmunication between th e pilot, ground bases and ot he r aircraft.The substan tial roll over structure immediate ly forward of the radio com par tment would save many pilots during landing or take -off accidents

40

P-51 MUSTAN G

ABOVE This teaching aid displays the Mustang's relatively simple hydraulic system

Fitted to its dolly,a co mpleted P-SIA tail con e assem bly is ready to be moved to th e final production line

LEFT

PONY SOLDIERS

41

Highly detailed view of the cockpit of P-5 IA-I -NA sin 43-6055. with the rear quarter panels removed for additional clarity. Original contracts called for the cons truction of 1200 P-5 IAs. but th is was drastica lly cut back to 3 10 aircraft when th e Me rlin engine was introduced to the Musta ng airframe BELOW

42

P-S I MUSTANG

RIGHT P-SI A- I-NA sin 43-6008 was retained at the factory for the installation and testing of bazooka-style rocket launchers. The P-SIA was fitted with a three-bladed Curtiss C.S3D-F32/50700 electric propeller with aluminum blades - Musta ng Mk Is had steel blade s

and malfun ct ion ing o f th e coo lant scoo p co n tro l and lan d ing gea r ret racting mech anism du ring th e co ld weat her. Th ese d ifficulties and o the rs o f a m ino r nature were corr ected by Army personne l and the co nt racto r's rep resentat ives. The seco nd airplane was th o roughl y inspected by t he Flying Branch after delivery and was then turned over to th e Armament La bo rato ry for firing tests.' Although it is appa rent th at th e aircraft, as wit h any new type, had some development al p roblem s it is also obvio us th at the milita ry either too k t he ir ti me solving th em , or simply forged ahead on testing o t he r types at hand . However, given the fi nal overall co n trihutio n o f th e Mustan g to the Allied victo ry, Dill' must won der just what th ey were th in king. The few su pporters of th e new aircraft had a lo ng and hard fight ahea d to make sure that de velopmen t would conti nue, a nd t he warplan e would en ter service. During December 194 1, No rth America n was bu ilding 3 1{2 Mustangs per day to fulfil th e British o rd er, but Kindlc bcrger felt that he could raise prod uct ion to a who pping ten fight ers per day with in th ree weeks of a substant ial Army o rder, Co l Homer Sanders, frustrat ed co mma nder of th e 5 Ist Fighte r Gro u p in India, who se pilo ts were find ing it increasi ngly d ifficult to fight superior j apa nese eq uipme n t in P-40s, com men ted o n 26 August 1942 t hat , 'App aren tly t he go-ah ead signal was not given (for ~ Iu stan g produ ction ) o r th ere would certai nly he PONY SO LD IERS

43

some available fo r co mbat d uty by this time. It appea red th ere was a tenden cy hy th e Mat erial Division to hinder th e development o f t his airplane, wh ich can o nly he accoun ted for by t he fact th at it was st rictly a No rth America n pro ject and Material Divisio n could claim no cred it for it'. Bark at the facto ry, North American was in a t rem endou s sta te of flux . Bet ween the star t of the war in Europe and th e Jap anese snea k attack on Pearl Harbor (a period tha t spanned just two yea rs and two months), th e co mpa ny had go ne from a ca pability of bu ildin g 70 ai rcraft per month to a mass-production facility t hat could ch u rn out ]25 ai rcraft in th e same tim e period . Thi s had also been a period of frant ic h iring , th e co rnpa ny swelling from 3-l00 em ployees to ove r 15,000, with build ings being rapidl y erected to ha nd le prod uctio n. \Vith th e 150 P-5 1s now und er production , th e Air Co rps dec ided to con vert 57 of t hese airfra mes in to armed photo rcco n natssancc ai rcraft for use in Europe and Nort h Africa, whil e th e remain ing 93 x tustan gs 0 11 th e o rde r were transferred back to the RAF as Mustang Mk. lAs. It is int eresting to note t hat

44

P-51 MU STANG

all these aircra ft were fitted with fo u r 20 111m ca n no n in place of th e ma ch ine guns . Th e can no ns ca rried 125 round s per gu n, and five rounds wit h linkage weig he d th ree pounds. Th is co mpared to o ne pound for t h ree .50 cal rou nd s and lin ks, and 011(.' pou nd for fin' 30 rou nd s and links. Nort h Am eri can 's cost to

A·l6A·I·NA sin 42-8 3934 is raised in a cradle for the test firing of its weapo ns.Th e bomb

racks were set close r to the landinggear to benefit from th e greater strength o f the wing structure.A·36 prod uct ion totalled 500 aircraft (NAA cln 97·15881 to 16380). and con sideration was later given ( 0 putting the type back into production since it had proven so effective. but Merlin producti on had by mat time completely ecl ipsed th e

Allison line

produ ce th ese ai rcraft was S26,741, but whe n p rofit and governmc n t furn ished equipment were added, th e price wen t to S5H,69H. Of th e aircraft pull ed fo r ph ot o-recon co nvers io n, th e :U rd and I0 2n d airframes in th e P-Sl co n trac t were withheld by Nor th American fo r cx pe rime n ta l engine wor k. The prot ot ype camera ins tallation was u nderta ken at NAA (P-S t -I -NA), while th e remai ni ng S4 were dep ot modifi ed as P-S I-Z-NAs, but were later redesignated F-6As_ In an attem pt to given thi s va rian t 50111l' special d istinction, th e nam e Apach e was briefly adopted . The Air Corps' next o rde r was for a P-5l of a dif ferent flavou r. On 16 April lY4Z, co ntrac t AC-Z7]96 called for t he constructio n o f 500 NA-97s - wh at wo uld become known as til l' A] 6A. Th e effect of the Luftwaffe's d ive-bom ber. or Stuk« , fo rces had been horrif yingl y portrayed acro ss th e co u nt ry's newsreel scree ns ea rly in the war, an d to t he public, and perhap s the m ilitar y too , th e dive-bomber was a terrif ying th reat th at seemed un sto ppabl e. Only experience wou ld pro ve t hat th e di vebomber, althou gh highl y effective in its design ed role, was at th e mercy of a stro ng fighter force. The Air Co rps real ised th at it lacked just suc h a weapo n. so No rt h Ame rican, with th e m inimu m n u mber o f mod ificat ions, co nve rted th e P-5 I int o a div ebomber - th e A-] 6. Thi s aircraft featured speed brakes built in to th e top and botto m win g sur faces, alo ng with a bom b rack under each Wing. Fitted wit h six .50 cal machine gu ns and ZCX.> round s pl'r gu n, th e A ':~6A (br iefly nam ed In vad er ] would beco me an important stepping stone in th e developmen t of till' Mustang, since it ad ded a ver y effective gro u nd attac k roll' to the aircraft's profile. \Vith th e a\v ard ing of th e :\ -] 6 co n trac t, and fur t her testing on earlier aircraft un derway, th e mo me n to us d ecision was mad e to o rde r a fight er variant of th e Mustang fo r th e Air Co rps. Fitt ed wit h t he new Allison V-17 1O-HI, IZOO exa m ples of th e 1'• .'i t A were ordered o n Z] Jun e 194 Z under co n tract r\C-]047Y, wit h the factor y dcsign atlon NA-99. As production fo rged ahea d , repor ts were comi ng hack from t he co mbat fron ts calling for modifi cation s or Impr ovem en ts to til l' basic design , and one of t hese was a sand filter ing vystem for the Alliso n car burertor since No rth African sand was redu cing reliahilit y o f th e Allisons. The p-s l A wo uld he fitted with four .50 cal Brown ings (two in each wing pan el ) and associated magazin es to carry IZ60 rou nds of amm unitio n. As with virtu ally any othe r co mba t aircraft , weight began to grow as th e ai rcraft neared series p rodu ctio n - t he co mbat load of the A-model was X600 lbs, and thi s further increased to 9600/1 0,:100 lbs if 75/1 50 gal d rop tank, were fitt ed . PON Y SOLDIERS

45

With th e awa rdi ng of the P-S IA cont ract, ext reme ly high levels of ma ss product ion were plann ed at Nort h American, and assembly lin es ca pable of co nst ructing 20 aircra ft per day were set in place. The need fo r new fighters was so great t hat th e or iginal co ntra ct for 1200 P-SI As was sup pleme n ted wit h furth er orders for 1050 aircra ft. However, t he P-SI A was to becom e a fairly limited prod uction fighter as orde rs were soo n slashe d to just 3 10 aircraft. The reason for th e dr astic red uction in n u mbers was t ha t th e Mustang airframe had been ma ted to th e vastly su perior (at med ium to high altit ude ) Roll s-Royce Merlin soon after produ ction of t he P-SI A had co m me nce d. Co mhat histo ry wo uld soo n be mad e . . .

To co nvert t he basic Mustang de sign int o th e A-36A, NAA enginee rs ex pended 40.000 manho ur s o f w o rk - o ne suc h modficat ion follo w ing th e fitm ent of dive br ake s saw th e pitot tube reloc at e d to t he starboard wing, Th e A-36A re taine d the NA·73's no se- mounted .50 cals. however. Mechanics are seen her e running up the Alliso n V- 17 10-87 prior to t he aircra ft's acce ptan ce by the milita ry. N ote t he dual landing lights in th e leading edge of the left w ing

46

P- 51 MU STAN G

CHAPTER

rn ONTO BERLIN

W ITH T HE ALLISON-POW ERED Mustangs. Nor t h Amer ican , the USAAF and th e RAF realised th ey had an excellent airf rame mat ed to a not-ideal engi ne . However, t his was not a criticism of the V- 1710, for th e engine perfor me d very well wit hin t he regime for which it had been d esign ed. Ho wever, as the war rapidly progressed, it became obvious that th e air war was going

to be fought at great altitudes - an arena for which the Allison was not suitable. Sometimes a momentous trend sta rts o ut in a thoroughly mundane manner. Dur ing 1942, Wg Cd r Ian Ca m pbell-O rde , com ma ndi ng o f ficer of t he Air fig h ti ng Devel opm ent Un it (AFDU) at Du xford, called h is frie nd Ro nn ie Ha rker an d told

him that one o f th e new Allison Mustan gs was at th e ba se, and invited hi m to co me an d fly t he figh ter. Har ker, Roll s-Royce's service liaison pilot, qui ckly accepted the invita tio n and headed to Duxford . whe re he flew Musta ng AG4 22 (lat er aba ndo ne d in flight on 2 October 19..l ] when its engine qu it while serving wit h No 4 1 Operationa l Train ing Unit ) o n 30 April 194 2. Harker had previo usly flown th e Alliso n-powered Cu rtiss Tomahawk, and was very war y of American claims to high performan ce. However, he was mo st impressed by t he Mustang, and th e next d ay sent a report to Rolls -Royce whi ch , in pa rt, read , 'This ai rcraft sho uld prove itself a fo rm idable low and mid-altitude fight er. It closely resembled a Bf 109F, probably due to its being designed by o ne of t he Messersch m ttt d esigners, wh o is now wit h th e North America n Aeropla ne Co (t h is, of course , was incorrect , as Schm ued was never em ployed by Mcsscrsch rnirt, hut th is sta rted a trail of m isinfor matio n th at wo uld bother t he designer fo r the rest o f h is life). The po int whic h st rtkcs me is t hat with a powerful and good engine like th e Merlin 6 1, its performa nce sho uld he o ut standi ng, as it is 3S mph faster t han a Spitfire V at roug h ly the same pow er'. Harker's qui ck ca lculations showed th at th e Alliso n Mustan g was 30 mp h faster at 5000 ft and 35 mph faster at 15,000 It th an t he frontli ne Spitfi re :-lk V.

The top per son nel at Rolls-Royce too k hi s suggestio ns very seriously, and moved rapid ly with a secret mem o dated 14 xtay O N TO BERLIN

47

194 2 from E \ '1 (late r Lo rd ) Hives, genera l man ager fo r Ro llsRoyce Derb y, sta ting, 'I feel m yself th at it might pay a very goo d di vid en d (t he co nversio n to Rolls-Royce power), if it ca n be don e qu ickly, to inst all t he Merlin XX in thi s mac hi ne. It wo u ld be a relatively qu ick job , a nd m ight fill a very usefu l inter im nich e u nder existing con d itions. I am en deavo uri ng to ob tai n perfor man ce data abou t the ai rcraft so t hat th e ga in th at mig h t he a n ticipated can be estima ted. I recall th at Air Commo do re R R Ma nsel l a nd E T Jon es, whe n in th e USA, d id suggest t hat th e Packa rd sho uld he fitted into th e Mustan g ai rcraft, hut it d id n ot get a ny fu rthe r'. However, t he Air Mini str y vo iced some concern since a stro ng co m mitme n t ha d been given to the prod uct io n of the Spitfire Mk IX. It felt th at th e mod ification of t he Mustan g wo uld d raw va lua ble resou rces away from gett ing th e Mk IX into th e fro n tli ne to comba t th e Luft waffe's pote n t new t hreat - th e Fw 190. Thi s left Harker part icu la r per plexed , and he late r wrote, 't ha t my proposal was u n rea listic, th at t he Air Min istr y wo u ld n ot app rove an d th at th ere wou ld not be any engi nes avai lab le a ny how as th ey were all requ ired for the Spitfires - a nd why waste time o n a n unt ried Amer ica n-b uilt aeropla ne!' 48

P-S I MUSTANG

LEFT With its landing gear firmly chocked and tail raised to simulate level flight attitud e, a natural metal P-5 IB has its four .50 cal Brown ingAN M2 machine guns tested and bore sighte d at the Inglewood factory. Building Mustangs had become an aroundthe-dock effor t by this stage of the war. and e ngine runs and gun fi ring filled the night-time hours. This view shows the P-5 IB's Hamilton Standard 24050 fourblade propeller to advantage along with the canvas dust cover s installed inside the landing gear wells to kee p the interiors free from dirt and grime. Howe ver, in the fie ld, crew chiefs usually dispensed with the covers since the blocked access for mainte nance. With the addition of the Merlin to the Musta ng airframe , the fourblade wide chord propeller became nece ssary to abso rb the increased power at higher altitudes. Also a new. and heavier, radiator was required for better cooling charact eristic s

W hile Rolls-Royce proceeded with the creation of the Merlin-powered Mustang X, similar activity was taking place at NAA with P-51 USAAF sin 41-37352 becom ing the first American Mustang to fly powered by a Merlin. Finished in stand ard O live Drab and Ne utral Grey camo uflage, the aircr aft re tained its four 20 mm cannon , but featured an entirely new air scoop similar to the eventual production sta ndard item . Packard Motor Cars was licensed to build the Rolls-Royce Merlin 61 as the V- I650-3, and two early examples were shipped to No rth American for installation in the aircraft that would initially be designate d XP-78.The con tra ct for the se conversions (USAAF sIn 41-37421 being the oth e r airframe) was signed on 25 July 1942, with the factory designation NA-I 0 I being assigned to the aircraft. Note the NAA logo on the vertical fin.The conver sions were carried out in a building ABOVE

se parate from on-going Mustang production, and although it appea rs that the co nversio n to carry a Merlin was fairly straight. forward. it was no t, and tens of thousands of e nginee ring hours were exp ended to ensure t hat the mod ificatio n work was a success .A new mo to r moun t and cowling was requ ired, while the forw ard fuse lage had to be strengthe ned. Also, a new air scoop and radiato r, as well as a supe rcharger, nee ded to be incorporated into the P-5 I airframe.The V-17 10 had tipped the scales at 1335 lbs (dry), while the Merlin weighed 1690 lbs. The latter's four- bladed Hamilto n Standard pro peller was also heavier than the Allison 's 'th reeblader'. Both the XP-78s retained the four 20 mm cannon of the P-5 Is from which they had been co nve rte d, but the inte ntion from the start was to equip the production Merlin Mustang wit h four .50 cal Brownings

O N TO BERLIN

49

The Rolls-Royce conversions were more functional , and rather than being aimed at mass production, they were basically utilised to prove that the mating of the Merlin and Mustang would wo rk. As the first aircraft so converted. Musta ng IAL975/G (the G denoted that the aircraft was involved in a classified, and important, project. and should be kept unde r consta nt guard when on the gro und) underwent several cowl ing changes. Fitted with a Me rlin 65 driving a 10ft 9 in diameter Spitfire prope ller, the aircra ft completed its first flight on I3 October 1942 with Capt R T Shepherd in co mmand . On this flight a speed of just 376 mph was reached befo re the cowling started to come apart following a build up of pressure . Further modifications saw a dramatic rise in performance, and one Ro llsBELOW

50

P-5 1 MU STAN G

Royce official wrote to another, 'The speed realisation is most encouraging. Soon we shall have a scream for Mustangs instead of Spitfire IXs!' In the wake of t he first flight Ro lls-Royce engineers calculated that fitting the Merl in 65 to the Musta ng resulted in the aircraft suffering a 44 per ce nt loss in directional stability - or the equ ivalent fin area of 3.8 sq ft. In order to rectify th is situation, a joint Rolls-Royce/NAA dorsal fin modification was proposed, which added another two square feet of area. However. directional sta bility pro blems remained a feature of the Me rlin Mustang until the introduction of the P-5 IH, with its ta ller vertical fin.As for AL975, the aircraft was operated by Ro lls-Royce until struck off charge on 5 April 1945 and scrapped - certainly an unfitting end for such an historic aircraft

This pho tog raph is of interest since several sources have listed t he aircraft featured as being the first NAA Merlin Musta ng - sin 41 -37352. Ho wever, compare this photo with the identified shot of '7352 on page 49. and note that this aircraft has a complete ly fresh paint scheme and unpainted sta inless steel exhaust sh ro uds. The aircraft also has the early national insignia and the landing gear o leos are exten ded to their maximum length, which may indicate that it lacks an engine or that the oleos we re over-in flated for some other purpose.The most noticeable difference is that the wing is complete ly devoid of 20 mm armament. Note the barrage balloon in the background - Mines Field was ringed with these as a defence against a Japanese surprise attack RIGHT

Despit e o fficial reluct ance fo r th e Merlin Musta ng. E \V Hives used h is polit ical power to have t hree aircraft tran sferred to t he facility at Hucknall fo r co nversio n wit h Merlin powerplants. Rolls-Royce freely let North Ame rican know wha t t hey were doin g. NAA was not u na ware of t he benefits of th e mod ifi cation, and o ne of the cha m pions of th e re-engint ng programme was Maj Tho mas Hitch cock, assistant air attac he at th e US l.mbassy in l.ondo n. Ill' issued t he fo llowing mem o, da ted B October 1942, 'The reaso ns for th e rem arkab ly low d rag of th e Mustan g arc not fully understood o n th is side of th e ocean. The English think it is o nly partly du e to the laminar flow wing. The Rolls peopl e became very much interes ted in t he possibilities of the Mustang airfra me with the Merlin engine. Estimates were made as to the speeds tha t could be obtained with the installation of th e 6 1 and 20 Merlin. The Air Minist ry ins tructed the Rolls people to install five Merlin 61 engines in ~f u s t a n g airplanes . Simultaneously with this development it was arranged to have the North America n Co m pany install a Packard version of the Merl in 6 1 in the xtusrang airframe. Requests were sent to the United States to have the Packard Co mpa n y sta rt manufacturing Merlin 61s as promp tly as possib le. 'The inte resting qua lities of the xtusran g airframe were brought to the attention of Gene ral Arno ld an d Adm iral Towers when th ey were in Lo nd on June last, by th e America n ambas sador 1I0l1 n C \Vinan t), Air Chief Marshal Sir Charles Port al, O N TO BERLIN

51

ABOVE A comple te P-5 1B motor mount in a jig,awaiting installation on an airframe. Totally different from the Allison mou nt, the unit was relatively simple and very rugged. Once in combat, it was found that a thorough inspection of early P-5 1B engine mounting bolts and nuts was required, for the stress of high speed, high G, combat manoeu vring in early 1944 resulted in the Merlins tearing away from the airframes .Technicians soon discovered that the engine mounting bolts and nuts used on early pS IBs were not strong enough to retain the Merlin under these condition. Replacement by bolts of greater strength quickly cured this dead ly problem

52

P-51 MUSTA NG

'Rosie the Rivette r' torques exhaust stack bolts on a Y·1650· 3 as it rolls down the production line. Note the custom tool holde rs that would mount on the bare metal cowl former for easy access as equipment was installed.This view shows the header tank. which was a reservoir for engine coolant, and separated air from hot coolant exiting the engine. The header tank was a complex piece of equipment built by NAA and fitted with four Acme Aircraft castings (exit and filler nozzles). The v. I650-3 was equipped with a two-speed. two-stage. supercharger at the rear of the powerplant.The supercharger could produce a sea-level atmosphere OPPOSITE RIGHT

within the induction system , and this allowed the Me rlin to pro duce more horsepower at 25.000 ft than the Allison could at full take-off powe r - thus creating the power needed for the long escort missions into enemy territory

ABOVE Detailed view of the left side of a partial p·S I B fuselage, showing the relative simplicity of the Mustang's construction.The gear handle, trim console and underwing sto res salvo are all in place, as are th e hydrau lic lines for the retractable tail whe el.The large meta l bar in the middle of

the fuselage was part of th e roll. over structure to protect the pilot, while the circular open ing to the rear was an acce ss panel fo r the fuselage cables.The brown leathe rette aircra ft documentatio n case was immediat ely behind the rear window. Note how th e fo rward portion of the fuselage

was painted in 'NAA Green ', while the rear sectio n was left in bare metal

ON TO BERLI N

5]

ABOVE Simple yet rugged. a

P-S IB rudde r is seen before re cei ving its fabr ic co vering.T he re cognitio n light a nd w ir ing are in

place. but t he large slot awaits installation of the phenolic resin trim tab .Written markings are still on the aluminum skin. and it

is interesting to note that these un its never received a protective spray of zinc chro mate .The rudder utilised a single spar with flan ged alc lad ri bs attache d. a V-

t railing edge piece and a beam for attachment of the trim tab .The leading edge of the rudder was cut o ut fo r the vertical tai l's hinge fitti ngs. the un it be ing hinged to t he ve r t ica l tail w ith thre e seale d

54

P·51 MUSTANG

ball bear ing fittings.The rudder was dynamically balanced with a 16.6-lb lead weight fitted to the top. while an addit ional balance weight at th e botto m of the leading edge helped reduce static unbalance.The trim tab was also hinged by three seale d nee dle bearings REMAINING PHOTOS The windshield. canopy st ruct ure and rea r panel windows for a P-5 1B. Although it may lo ok simple. th e canopy frame work had over 1200 pieces.The main portio n of the cano py had a panel o n each side tha t co uld be manually slid to the rear by the pilot via the knobbed handles seen in the photograp h.The flat forward sect ion of the cano py was a fiveply.laminated 11/2 inche s thick. bullet pro of and slante d 31e back from the vertical when installed on the aircraft. The windshie ld's side and upper panels was 3/ 16 inch thick plexiglass

ON TO BERLIN

55

,

Interest ing view of a main landing gear leg being installed in t he win g of a P-SIB. Th e landing gear

was made und er co nt ract by Bendix. N ote how the leading porti on o f th e win g has received

its layer of filler and a coat o f primer.At this stage of asse mbly. th e phenolic resin ex t ern al sto res shackle has also been installed . Th is pho tograph was ta ken o n 26 August 1943

56

P-S I MU STAN G

Ch ief of th e Air Sta ff, Air C h ief Ma rsh al Sir Shol to Douglas, Com m and er in Ch ief Fighter Comma nd , a n d Air Mars ha l F J Linn ell, Min ist ry of Aircra ft Prod uct ion Resear ch a n d Developme n t. Rober t Lovett, Assista n t Secreta ry fo r Wa r fo r Air, was a lso advised by letter, dated 5 Ju ne 194 2, of th e Impor tan ce wh ich Eng lish a nd va rio us Ame rican rep resen tatives att ach to th e Mus ta ng air fra me a nd t he dc stra bi ltty o f e ne rget ica lly pursu ing the Merli n de ve lopme n t. ' Mr (Ph il) Legarra, Nort h America n represen ta t ive, reported whe n he ca me back fro m the U.s in t he ea rly pa rt of Septe mber th at the Mustang h ad t he lowest prior ity th at co u ld be gra nte d to a n ai rp lan e. 'The Must ang is o ne of th e best , if n ot t he best, fighter airfram es that h as been developed in t he wa r up to da te ... its develop me nt a nd use in this t hea ter h as suffered for var ious reason s. Sired by th e Eng lish o ut of a n Ame rican mot her , the Mu stan g h as had no paren t in t h e Army Air Co rps o r at Wrigh t Field to app recia te a nd pus h it s good poin t s. ' Im po rta n t peo ple o n bot h sides of the Atlan tic see m more int erested in pointing wit h p ride to t he devel o pme n t o f a 100 per cen t nation a l prod uct tha n t he y a re co ncerned wit h th e ve ry d ifficu lt p robl e m of rap id ly developin g a fighte r plan e that will be su perior to an yt h ing t he Ge rma ns h av e.' Alt h oug h Hitch co ck's feelings we re well-place d , he did not kn ow th at wor k was goi ng on to make th e Merl in Mu stan g a

BEL OW Photographed outside the asse mbly hangar under the camouflage netting, t his view of a P-S IB wing shows the large stress doo rs to advantage. Made of Alclad 24S-T aluminium. the str ess doo rs offered access to the wing fuel tanks. while also forming an essential part of the wing's struc ture.The leading edge of the wing has rece ived its coating cfdum-dum' filler (a material that was applied to help maintain the desired laminar flow). while a quick coa t of primer has been sprayed over the fo rward portion of the wing.The main landing gear is inside the wing, but the gea r doo rs have not bee n attached .

Early pheno lic resin ext ern al stores pylons are in po sition .The long pipe running do wn the cen tr e of th e wing is th e engine co mpart ment scupper drai n which, when completely assem bled. would dra in out of the left side of the scoop.The scupper was in place to drain anything leaking from the engine compartment. NAA employee Geo rge W ing invented an extra hard rivet for use during the construetion of the laminar flow wing. When utilised in the wing struct ure. it replaced nearly 800 rivets and bolts . giving a 60 per cent weight saving, while also increasing shear st rength by 200 pe r

cent. W ing wou ld go on to found his ow n co mpany, producing aviation components and even an unusual two-seat twin-engine d privat e aircraft called the Wing De rringer

ON TO BERLIN

57

realit y. Hap Arnold had see n th e pot ential in th e design a nd Brig Ge n O liver Echols, Arno ld's Chid, Mater iel Division , was in stru cted to get th e co nce pt in to rea lity. Fro m 1940 o nwa rd s, Echols had been respo nsible for sett in g up th e license-built Packa rd Me rlin prod uction line, and he quietly made Slue that two n ew V- 16S0-3s were tran sferred to No rth Ame rican for th e XP-7H pro ject (the Mer lin Mustan g had been given t his new de signation, but it was to be short-lived) . In Britain , Mustan g A ~ f12 1 was sent to Hucknall o n 7 Ju ne 194 2 to form th e basis for t he first co nversio n. The aircraft was fo llo wed by A1.96 3, '\1.975, AM203 a nd ,\M 20 X (t he last two were ad ded to t he Rolls-Royce prog ramm e hy till' requ est o f th e USAA F). SOI11l' initial flyin g was do ne with Ai\f12 1 in its stoc k co nd itio n to obta in perfo rm an ce data . At an early stag e in the co nversio n it was decided to use the Merlin 65 in stead of th e Merlin 6 1, and th e first aircraft made read y for fligh t was AL9 75/G, whi ch flew o n 13 October 1942. Back in Inglewood ,

58

P-51 MU STAN G

LEFT A batch of early B-mode ls comes together in the Inglewood plant. It is int eresting to note how Ame rican aircra ft manufacturers picked up o n the mass production techniques created by Henry Fo rd for his automotive empire. Close examination of the photograph show how various components were added in a logical order as the aircraft progressed down lo ng lines befo re making a tight l.I-turn and heading down anot her long st retch. all the time being pulled by an electric hoist-At the ext re me left background. Packard Me rlins were

placed in engine mounts, while partia l fuselages were assembled. On th e next turn , fuselages became more co mplete. while tail cone s and tail surfaces wer e installed as the fuselage passed out of the left side of t he photograph.Taking one more If-turn, the wings and engines were installed. along with many other details including the canopy structure and plexiglass (which still wore its pro tective paper coating fro m the manufacturer) .These aircraft were P-SI B-S-NAs

ABOVE Facto ry lay-out illustrating the flow of parts and components into complete P-SI B Mustangs

ON TO BERLIN

59

ABOVE Nearly complete P-SI B tail cones and tail surfaces in their jigs awaiting transfer to the assembly line on 10 January 1944

60

P-S I MUSTANG

LEFT Electric overhead hoists were utilised to move the tail sections to the assem bly line. Once the P-SI Bs entered combat. Base Air Dep ot Areas in the United Kingdom we re set up to correct faults found in th e B-model after its initial com bat experiences.These faults were eithe r rect ified in the field o r incorporated in the NAA production lines. One fi x was the reinfo rcement of the horizon tal stabfflser afte r it was disco ve red that at high speeds o r whilst being handled carelessly (o r enthusiastically). Merlin-powered Mustangs exhibite d a pre vio usly

unsee n weakness in the tail. which sho wed up as be nt metal o r. in the worst instance. com plete str uctural failure.A doubler plate was prod uced fo r reinforceme nt of the ho rizo ntal tail spar until a strengthene d co mponent could be inco rporate d int o the production line

ABOVE Another view of the P-Sl B production line. Unde r a large Ame rican flag. the V-16S0-3 powerplants can be seen to the left and the very basic fuse lages star ting th eir journey at Station I imme diate ly alongside .The latt er then mo ved up and do wn the rows whe re . at each station . specific co mpo nents and equipment was added . Piles of parts can be see n at each statio n including seats, sco ops, cowlings. et c.The se supplies we re replenished during the day by cons ta nt delive ries fro m the parts dep ot

ON TO BERLI N

61

ABOVE Bcmod el Mustangs head toward com pletion. The dolly which moved each aircraft thro ugh assem bly is clearly visible. As can be see n, vario us wing access panels were not in place when th e wing recei ved its coa t of primer. One worker is hammering sheet metal around a left wing gun po rt. while three colleagues are finishing cockpit installations.Along th e wall.worke rs' cloth ing is o n hangars th at were lifted high from the shop floor. appar ently as a fire prevention aid.The armour plate aroun d the head er ta nk and canvas f itting over the nose gear case are also installed. Note B-25 Mitchells also nearing com pletion on th e left side of the photo

62

P-SI MU STA NG

RIGHT Up on jacks. an early model P·5 J B undergoes gear swing tests. with power being provided by a hydraulic 'mule' locate d under the propeller.The canop y has bee n rem oved and placed o n the wing.Workers found t hat co nducting such wo rk under the camou flage netting was preferable since it he lped diffuse the hot sun or bad weath er

BELOW A Mustang is re mo ved from its dolly.This particular aircraft has had the cowlings taken off. Gene ra l Tires featu red the diamond tread common to th e tyres o n many W orld Wa r 2 com bat aircra ft - it was felt that this type of tread was better suited to grass fie lds or unpre pared runways. Gene ral. Firesto ne and Goodyea r all supplied tyr es for the Mustang prod uction line

O N TO BERLIN

63

Firmly cho cked, P-51 B-INA USAAF sin 43-12342 is run up by a mechanic pr ior to a test flight. Dou glas SBD Dauntl esse s can be seen be ing prepared for a sim ilar ta sk in th e backgro und . The aircraft carr ies the shortlived red surround to the nationa l insignia, and alth ough just o ut of th e fact ory, the P-5 1B's flat Oli ve Drab and N eutra l G rey camouflage already show co nside rable wea r just from use around the factory.T he se rial num ber wa s painted o n the vertical tai l in Insignia Yellow. USAAF o rders led to so me confusion on how such a numbe r, or 'radio call sign', sho uld be presented. On 13 BELOW

64

P-S 1 MU STAN G

Januar y 1943. Spec. 98-241 OS-Q. Amendment N o 2, Paragra ph E·6A read . 'Each air plane shall have a radio call nu mber painted on its vertical tail surfaces.The radio call numbe r shall co nsist of at least four numerals and shall be de termined in the following manner:Th e firs t nu mbe r and th e hyphen shall be om itted from the serial number of the airp lane , using zero wh e re nece ssary between th e yea r de signated and the serial num ber to make at least four numera ls'.The document co nt inued,' Fo r light coloured backgro und s, the numbe rs shall be black in accordance w ith colo ur chip N o 44 o f Army

Air Force s Bulletin N o 41, an d fo r dark backgrounds , the nu mbe rs shall be ye llow in accordance w it h co lour chip N o 48 of Army Air Fo rce s Bulletin N o 4 1'. Even th o ugh this clarified the situ at ion, m istakes were st ill made at various factories and es pecially in the field wh en th e aircraft was re painte d

test pilot Bob Ch ilto n too k the first NAA Merlin-po wered 1'-51A conve rsion, USAAF si n 41 -3 7352, a loft o n :10 November 1942 , so it was a close thing as to which coun try too k the honour of flying the first Merlin Mustan g, Actually, NAA and Rolls-Royce freely exc hanged data as the co nve rsions went along. I.t Col Cass Hough h ad seen t he potential of the Me rlin Mustan g from the sta rt, a nd as a tec h nica l officers at HQ Vilith

High-angle view of P-51 B-I -N A

Fighter Co m ma nd, he kept in close touch wit h Roll s-Royce liai-

ente red com bat, distinguishing

son officer \ Villiam Lappin . w ho eventually invi ted Hough to Hucknall to fly one o f th e new aircraft. ') just assume d it wou ld

hopefully prevent accidental

be a co nvent ional airplane because nobod y to ld me anything. The on ly informa tion I got from Bill Lappin was that the first flight s that had been m ade up at Huckn all resulted in th e pilo ts being just d eligh ted with the airplane. 'Flying a new airplane, I always pu t the power 0 11 easily at the start to ge t the fee l of th e airpla ne o n th e ground, th en gradually give it po we r, \ Vh en I got airborne, a couple of hundred feet off the gro u nd , I pu lled up the gear and decided then I'd sec

USAAF sin 43- 12408 displays the Mustang's broad and simple wing structure to advantage T he square wing tips bor e some similarity to those of the Luftw affe's Bf 109, and w hen the Mustang wing bands were required to firings on the fight er.Th e easy staining of the camouflage paint is readily visible, as are the tapedover gun po r ts for the four .50 cal Brow nings

how it would climb from scratch. I pour ed the coal to it and th e

O N TO BERLI N

65

Rows of Mustangs (for both the USAAF and RAF) indicate the rapid build-up of production at NAA In RAF service. the aircraft was designated the Mustang HI, and even tho ugh they were fi nished in full grey/green camouflage. they car ried USAAF insignia on t heir fuselage sides pr ior to delive ry.The closest Musta ng III to the came ra is FX968, which served with the RAF until being struck off charge on 24 July 1944 ABOVE

Detai l view of the rear cockpit area of a P-5 1B7-NA that has had the rear quar ter panel plexigtass removed to display the battery holder and racks for the radio transmitter and receiver (both units of which were removed from the aircraft). The large black rubber 85 gallon fuselage tank is also visible.along with its vent tube .The new tank was introduced on the P-5 1B production line, and numerous earlier examples were retrofitted with the unit. Made of the same self-sealing rubber material as the OPPOSITE TOP

66

P-S I MUSTAN G

wing tanks. pilots had to carefully monitor the tank, for when full, it placed the centre of gravity at its aft limit.Accordingly. fuselage tank fuel was utilised from the start of a mission, and manoeuvring was restricted until less than 25 gallons remained. However. the fuselage tank greatly increased the range of t he P-S IB/C. The ADF loop can be seen on the rear fuselage. while t he uppe r recognition beacon is fitted directly above the rear view glazing.The open access panels allowed work to be carried out on the electrical systems .The hand hold for the pilot is also visible in th is view. as is the black 'ground here' circle which was utilised when the aircraft was being fuelled.The gauge for the fuselage fuel tank (on a mounting above the vent tube ) has been taped over to avoid damage while equ ipment was installed or removed

Over a snowcrusted section of the San Gabrie l Mounta ins, test pilot Bob Chilton looks upward at the photographer in the B-25 Mitchell camera aircraft.The high angle view of the Musta ng emphasises how some pilots or anti-a ircraft crews co uld mistake the P-51S/C for the mitt Sf 109.This particular aircra ft is carrying two 65 galIon jettisonab le fuel tanks on the underwing pylons. Fuel gauges were not provided for the external tanks. and the pilot was requi red to rotate the fuel selector valve approximately every 15 minutes in order to keep the aircraft in trim. Prior to dropping the tanks . the pilot had to select an internal tank or the Merlin would falter as the fuel supply rapidly depleted. No boo st pumps were provided for the drop tanks. and fuel was forced out of them by a pressure of five PSI from the exhaust side of the vacuum pump. If this system failed. the engine-driven fuel pump cou ld draw fuel from the tanks up to an altitude of 10.000 ft OPPOSITE BELOW

ON TO BERLIN

67

Camouflage and bare metal P-S IBs are seen at the NAA plant as new unpainted Mustangs supplemen t the last camouflaged exam ples coming off the production line. USAAF sIn ABOVE

43-7 138 is a P-51B-1O-NA (398

examples of which were built), whilst the aircraft to the right displays a white cross under the individual aircraft data block. Such a marking alerted gro undcrews t hat the Musta ng was fitted with the 85 gallon fuselage tank. which required filling. Regarding the fuselage tank. Louis Wait. NAA administrative tes t pilot. commented,'The first o bjectio nable feat ure was t hat t he weight without external tanks was increased to about 10.000 lbs. which decreased the ultimate pullout fact or from an ori ginal t 2 G dow n to 9.5 G. but th is was not as serious as the fact that when

68

P-51 MUS TANG

the additional fuel was added . the airplane 's cen tre of gravity was placed so far aft that the it became longitudinally unstab le. This instability was particularly dangerous in that a pullout at high speed was always accom panied by a stick fo rce reversa l which. unless o pposed by the pilot. would quickly carry the airplane into an accelerated condition where the wings wou ld fail at the inboard end of the gun bay" RIGHT Nearly fully equipped P-5 1B cockpit. Items of note include rear view mirror mounted on the upper por tion of the windshield. a cras h pad atop the instrument panel shroud. and basic flight instruments arranged in the central panel. The devices mou nte d to the low er right and left windshields are movea ble fluoresce nt lights

ON TO BERLIN

69

aircraft snap rolled! Ro lls-Royce hadn't provided enough vertical fin area, and not eno ugh offset. ' I was eager to get it to altitude and sec how it performed because th at was the critical thi ng . I stu d ied th e fuel cu rves of th e Merl in in several other airframes so I knew what the ran ge of the airplane would be on interna l fuel, hut I did n't no w how t he ai rplane would actually hand le at high-a ltitude because no one had ever got an Allison Mustang abo ve 2-l,(X)() or 25,000 ft. O rdi na rily, the two-st age blowers - t he early o nes - were manually o perated o n th e Spitfires . I had just begun to think it was tim e to cha nge blo wers - I hadn 't even inq uired whe re th e hand le was for changing it - whe n, all of a sudde n, I got thi s big "c h ug" and a thu m p around 16,000 ft an d of co urse it was then in high blower. There was an auto mati c su percharger gear cha nge an d it was a co mplete su rprise. ' I go t up to about :n ,ooo ft with it and it was so man oeu vrable, and I co uld tell with out makin g any speed run s, assuming th e airspeed ind icator was calibrate d reaso nably caref ully, that it was pe rfo rm ing won derfully. I just couldn't believe so me of th e thi ngs J saw afte r do ing a couple of speed runs with it.'

70

P·51 MUSTA NG

Wi th its window s covered over to prevent reflection. the right side of a P-SI B co ckpit is illust rated showing such detail s as the aircraft o pe rating rest rictions plate. SC R522 and SCRSJ S radio co ntrol boxes

It sho uld be not ed tha t th e supercharger had th e ability to maint ain sea level at mos phe re from th e inductio n syste m to th e cylinde rs, whi ch allowed th e Merlin to produce more horsepower a t 26,000 ft than th e Allison could d ur ing- a fu ll power take-off. Th e Mustang Xs were rather crude looking aircraft with ungainly cowlings and cooling syste ms , but th e XP-78 was a much more elegan t package. However, th ey were also not without trouble. Using th e lessons th ey had learned with th e earlier scoops, NAA engineers created a new coo lant rad iato r and scoo p design that was successfully ma ted to th e aircraft. However, th e first en gin e run s on th e devel opment aircraft came to a quick end when temperatures rocket ed into th e red . Th is was ca used by et hy lene glyco l loo sening residu e in th e cooli ng tube, and clogging the new alu m in u m radi ator, which had been de signe d to be of less weight in o rder to avo id strc ngt henl ng the mounting area. Whe n Ch ilto n took th e first ai rcraft up, he was very pleased th at th e Merlin was exceed ing performan ce spec ificanon s. but afte r ap pro xima te ly -IS mi nu tes th e engine ove rheated and he had to make a qu ick landing with th e Mustang

Left side of a P-SI B cockp it. showing the t hro ttle and mixture control, bom b control and antisalvo guard. landing gear handle and rudder. elevator and aileron trim tab contro ls

ON TO BERLIN

71

AB OVE North Ame rican Aviation opened a new plant in Dallas,Texas, to facilitate increased Mustang pro duction (along with other types of aircraft, including the Texans seen in the background). The first Must angs built at Dallas were des ignated P-5I C-I-NTs and were virtually identica l to the B-models - the Dallas facility would produce a total of 1750 P-S ICs. This particular P-SI C- IO- NT is a 'presentation ' machine - an aircraft which had been 'bo ught' by donations from individuals, compan ies or civic o rganisat ions - in th is case Brandeis Aza No. 533 B'nai B'rit h. Fact o ries usually made quite a deal over these aircraft since they se rved as exce llent morale booste rs.Th is view shows the filled and painted wing to advantage, as we ll as the three co loured ident ification lights mounted under the right o ute r wing panel. Natural metal Mustangs had become th e norm following a major revision of Technical Order (TO) 07- 1-1 issued on 26 December 1943, which stated that t he exterior painting of USAAF aircraft was to be discontin ued (except for aircraft being supp lied

72

P-S I MUSTA N G

to Allies by the USAAF): 'Painting of the exterior metal surface of Army Air Fo rces aircraft is hereby discontinued . This does not, however, eliminate t he req uired identification dat a, insignia, anti -glare coatings and corros ion prevention. Man-ho urs ex pended on mainta ining existing camouflage finishes, now cons idered unnecessary, will be held to a minimum.'

RIGHT PackardV- 16S0-J Mer lin, with rocker covers removed, receives a spraying of preservative material prior to sea shipment to Great Britain. In the background can be seen Thunderbo lt s, Lightn ings, and an A-36 also being prepa red for ocean voyages.The large capped tank to the right of t he photograph is the afte rcoo ler filler tank. During August 1940, dialog was started between the American and Brit ish govern ments in order to forge an agreeme nt for license production of the Rolls-Royce Merlin by the Packard Motor Car

Company.An agreement was reached in short order, and RollsRoyce shipped over 2000 drawings to Packard t he next month. Three buildings were acquired fo r engine production, and a team of over 300 engineers was assigned to set up the Merli n for American production. The Brit ish metric system was reta ined, as it would have been too much work to convert, and t he Whitworth thread pitch was utilised on the basic eng ine while accessories were standard American AN units that could eas ily be obta ined and replaced under combat condit ions. The first American production Rolls-Royce was the Merl in 28, wh ich was similar to the unit in the Avro Lancaste r bomber and emp loyed a single-stage two speed supe rcharger.The engine was given the military designation ofV- 16S0, the V denoting the V- 12 configuration and the 1650 being the cub ic inches (actual cubic inches were 1649 but the figure was rounded up). Each Merlin had over 14,000 parts - more than double the number used in a Packard motor car.The super-

charger was the key to the Merlin Mustang's performance, and the addition of a Wright supercharger drive quill to the supercharger created the V- 16S03, which entered production in September 1943.In factory parlance. this became the 'high alritude' Merlin, compared to the V-16S0- 1 used in the Curtiss

P·40F.

trailing a tell-tale wh ite stream . Once again the radiator was clogged , and flight testin g cam e to a halt until the cause of the problem cou ld be found . It was traced to an electroly tic act ion between the various metals and the cool ant, which caused residue to be loosened . In order to overcom e th e problem , NAA contracted with the Harrison Division of General Motors, and a new radiator was bu ilt th at had a frontal area of 2.7 squa re feet. The scoop section had to be slightly redesigned for the extra weight, bu t the new radiato r had a separate section for supercharger coo ling, while th e o il coo ler was mount ed forward of th e coolant radiator in its own separate scoo p, with its ow n shu tter. Chilton resumed flight testing in December of that year, and was delighted to find the new unit worked perfectly, and th at performance was greatly increased over the Allison aircraft. The NAA co nversions involved two P-S1s - USAAF sins 4137320 /37469 (these aircraft also carried RA F sins FD4S0 an d FDSI 9) - which had been transferred to the Merlin Mustang

ON TO BERLIN

73

conversion pro gramm e. The conversion work o n the first aircraft was actua lly comp leted in just six weeks, and it was decided to d rop the XP-78 designation for the new aircraft and adopt th e designation XP-51B (NA-102) instead. Such was the USAAF's faith in the Merlin Musta ng that an ord er for 400 P-51B-l -NA Musta ngs was placed o n 26 August 1942 - almost three month s before the first flight of the XP-5 1B. A plan by the RAF to have its earlier Allison Mustangs conve rted to Merlin s was dropped in favour of obt aining new produ ction aircraft. North American officials serious ly co nside red th e impli cation s of mass-produ cin g th e ne w B-model alongs ide th e hu ge orde r for 1200 P-51As, and, acco rdin gly, a simp le and efficient produ ction lin e was designed and implemented tha t co uld acco mmo date th e delivery of 20 Mustan gs per day. However, th e superiority of th e Merlin P-SIB saw th e A-mo de l o rde r slashed to just 310 examples, and the assembly lin e was dul y mod ified to acco m moda te th e mass-prod uction requ ireme nts of the Packard Merlin instead.

74

P·S I MU STANG

Wh ile P-SI B prod uction reached a crescendo, NAA maintained a very active exp erime ntal shop that rea lised new co ncepts and impr ovements.This view shows bazoo ka-style rocket launchers fitted o utside of the norma l underwing pylons fo r te sting on a P-5 1B - such modifications were quickly and efficiently undertaken and se nt o n to flight test. As can be seen, with its four .50 cal Brow nings, six roc kets and two 500 -lb bombs . the aircraft became a potent ground attack weapon

CHAPTER

rn BUBBLE TOP

WITH PRODUCTION IN FULL SWING on th e P-SIB/C at both bo th th e Inglewo od and Dallas plants, constant improvement s and modification s were introduced on the production line as reports cam e back from the combat front . The BIC Mustangs, as well as th e majority of Allied and Axis fighters of that period , had can opies constructed from metal-framed plex iglass.

While efficient in protecting th e pilot from th e elements, the metal panels decreased visibility - especially at night or in po or weather - and o ne o f the complaints coming from th e frontline

was that th e P-SI B/C pilots suffered from poor cockpit visibility. This problem had, to a limited extent, been soived in the field through th e introduct ion of th e Malcolm hood mod ification. Created by the British , th e ho od was a semi-bubble unit wh ich repia ced the framed cano py on early Mustangs. Rails were added on eithe r side of th e cockpit wall to allow th e canopy to be slid back, but this 'field mod' was only an interim measure. The primary reason for the lack of o ne-piece clear vision canopies in th e early war yea rs was th at th e technol ogy required

to create a large 'blown' plexiglass transparen cy simpiy did not exist. How ever, th e incredible pressure of wartim e development

saw suc h technology and machinery qui ckly developed which en sured th at a bubble can op y could be created that would take the pressure of high speed flight and th e stress of combat. Thu s, NAA engineers began sketching out a drawing of a P-SIB with a bubble canopy, and the pap er result s produced a sleek lookin g aircraft with Vi rtually un precede nt ed Visibility. The ne xt ste p was to create a beaut ifull y crafted wind tun-

nel model so that th e bubble canopy concept could be tested. By this tim e NAA had realised the importan ce of havin g th eir own dedicated tunn el and, accord ingly, allocated a large sum of money and critical wartime materials to con struct it in a fortress-like concrete building at the Inglewood plant. Prior to th e advent of th e NAA tunnel, the company had to de pend entirely up on oth er local sites (espec ially th e one at Cal Tech ), which operated on a schedule giving a certain time to each manufacturer. Weeks, sometimes months, of precious time were often wasted in waiting for a chan ce to use these tunn els. With BUBBLE TO P

75

ABOVE The No rth American assembly hangars resound with the noise of P-SI D production in full swing.This photograph shows D-models rapidly nearing completion as they head toward the exit door - the lead aircraft has had its four-blade Hamilton Standard cuffed hydromati c prope ll er already fitt ed. Note the unco mpleted fuselages on the right that seem to head off into infinity. They wou ld finally make a 180" turn and head back towards the photographer as more and more equipment was added

76

P-SI MUSTA NG

RIGHT Testing out the bubble canopy co ncept in the new North American wind tu nnel. Built of mahogany and metal. and costing $20,000, the quarter-scale mode l was sanded down by hand and given five coats of lacquer so that it shined like a fine violin. Weighing 400 lbs. th e test mod el was fi rmly anchored to its suppo rt pylons, since the t unnel co uld produce air speed s of up to 32S mph.Wh en the model was set up for a test. a 3000-hp motor, driving a seven-blade 19-ft prope ller at a maximum of 700 rpm, could send the air flow back over the mode l at high speed.

The model was adjusted for the first run at a zero angle of attack in orde r to initially get nor mal reactions, its final setting being accurate to within III OOth of a degree .Allow ing for the weight of the model, all scales were set fo r zero

-

BU BBLE TOP

77

ABOVE Few of t he early fighters of World War 2 had cockpits which offered good visibility due to the built up canopies (a st ruc t ure t hat utilised numerous metal frames to hold plexiglass panels) then employed.The frames hindered vision under normal cond itions. and could play havoc if the aircraft was being operated at night or in poor wea ther. Accordingly. on 27 February 1943 two P-SI B-I-I O-NA airframes were bailed back to NAA for t he development of a bubble cano py which wou ld lead to t he production of a new Musta ng variant the P-51D. Bob Chilton is see n

flying P-SIB 43 - 12102 wit h th e

sleek new cano py in place. From th is view. it is very evident how the visibility from the cockpit was drastically improved

78

P-SI MUSTANG

OPPOSITE TOP The fi rewall and oil tan k (note t he heavy duty st raps t hat wou ld keep the oil tan k firmly in place. even during the most severe of com bat manoe uvres) are attached to t he basic P-SI 0 fuse lage. to which the majority of interna l fittings and controls are already in place. Four longerons and formers com posed this simple. yet very rugged, structu re

OPPOSITE BELOW A P-SI D wing near ing comp letion. Note how the forward 40 pe r cen t of the airfoil has bee n primered. fil led and sanded. At this point. the basic landing gear structure has been installed. along with t he aluminium drop tan k/bomb pylons and stubs for the 5-in rockets.Also not the cr ude stencil application of the US national insignia.The large stress doors have not yet been put in place. waiting for the installation of the fuel tanks

BUBB LE TO P

79

the new tunn el, NAA engineers could run tests co ntinuously and quickly, covering a mu ch larger field t han befo re. The tunnel utilised a 3000-h p powerpl ant wh ich drove a seven-blade 19-ft propeller at up to 700 rpms, and this could get th e air mo ving at speed s of up to 325 mph. A 200-h p au xiliar y system supplied power for motors to run propellers in the models and fo r various other operation s. Scientific considerations governed all the details in the construction of the tun nel. The redwood test section was sup ported on steel 'I' beams, anchored at each end to the concrete porti on of t he tunnel. The power and propell er sectio n was dou bly strong, whilst th e walls of the con tro l and compu ting roo m were floatin g and heavily sou nd proofed. About 200 years ago , Venturi discovered that, as a passageway narrowed down, the flow of air through it gained speed - hence the Ventu ri effect and the NAA tunnel was built on that principle. The air stream narrowed down nearly eight times, making high speeds possible through the test section. The problem o f making the air flow smoothly arou nd t he square angles of the tunnel was solved by curved metal vanes or plates set up at the corners. Since a tem perature of 150 cenngrade might develop in the air stream during co ntinuo us op eratio n at hig h speeds, water-cooling o f the vanes was 0

80

P-5 1 MUSTANG

BELOW

Bullet-p roo f fuel tanks

aw ait installation in the wi ng. Wing conveyor lines A and B were phot ographed on 29 July

1944

Frontiel"S of J<'l"ee dolll Just as th e fr ontiers of Ameri ca gre w beneath th e flying hooves of the mu stang s, so today' s frontie rs of fr eedom are gua rded by iorth Ameri can Mustangs - swift pur suits named for the hardy strain of American wild ponies. These fleet, agile fighter s, in active service with th e RAF, are helping Britain att ain comp lete supremac)' in the air. er t s e t r t

•

It.

I( IS E '

P-SI MUSTA N G

81

rna

SATUIlO .U' EVE."iIt..;G i>OST

TODAY AND TOMORROW Today, tomorrow and until the war is won every All ison engine is built co a standard that em braces five " must" qualities:

*

Paformd1Ut

* Reliability on which our pilots can depend . * Smoothness co lessen pilot

that helps our fighters win battles.

. fatigue. range.

* Economy for greatest

* Durability for

ing readi ness.

fighting

maximum fight-

* Viral

now for our

Byers, these are also characteristics you will want _in engines that will power postwar planes.

POWERED BY ALUSON

Tbe _rJ--5"POO AUr- .... ~ '1l. s: A...,.4>. F(naf P"-' tix foil"""" pI..-:

gi-f l>talt for

P'J8-L~,

P-J9 -AI'~.

P"4"-W.""'•• A-j6..JP11-M." ,-S

LIQUID-COOLED AIRCAA" ENG INES

DI V IS IO N OF

Indianapol is, Indiana

•

_ _ _82

P·51 MUSTAN G,

_

INVI SIBLE CREW" The " STROMBERG" Inje ction Ai'c,oft Co,b", et Of is new in p. incip le. Ai. flowing inTothe co.b".etotna licall y co mpe nsa ' e s f a. a ll a !lit " de de nsit y ch a nge s. " STROMBERG" lniection Air croft Co,b,,'elon Q1"e s1anOo,d l!'quipmeJ'lt on most Ameticon o irc,oft.

P-SI MUSTANG

83

•

mort~ I2lmcrican ~·51 IDlllftallB ijiB~tcr

liin Xirfbldrriliigd (iinbrdrr ~irr1JlaU,~r01lrUtl. 3n bIn mit longlr 9l1\1.langlm.ftlllon, ':tragniidiln monliltl: i5t~ Irm :Hump!. gro ~lm baudiwnr. 50,folibrigl!JJlafdiinlngll1l1blf figrm .ltiibllr.liiniliftoiflllnb (!jill 013 ba3ldinlUnljlln!l11ng I . . Il!.!!ln./'"'..... . inllitwrrl. lun i ATTENTION LUfTWAFFE! Keep away from this plane. Expect to see it on the farthest trip American bombers make. Expect to see it up high-40.ooo feet-but don't e xpect to see it for long, because the Mustang t ravels at over 425 m p. h.

And you can expect to see more and more Mustangs, too.The men and women at Xorth American are stepping up production every month. So when you see this high fighting. far flying ~I ustang, look out. Luftwaffe. Get out of there quick!

North Amer ica n P-51 Mush.ng Fi9 h le r

Nort h _'\merican A,riation Sets the Pace WI . ... 11:I ' LAN IS I MAl .... u H UO UH U • • • lite B-2S .\fitcMll /.trmobc!r. A. T .(i T=z" a>J>tl>tlt t'i,i..n. P-51 M I4 It1>tT. ••..fJrlh Amaic8" A ....tn". l rse ,u..... Aircraft War f'rrx),.dw.. C"~1lrl'L IN(. .'

_ _--"8:;:. 4

P·5 I MU ... ST ~A:.:;N~G~

_

w.

Flying 'Bazooka :\l YlTKYL'I A, Bt :R.\I A ... a l ap garrison is almost surrounded

by Chinese and American forces. but Jap supplies are still coming through. A P·S1Mu stang sq uadron is out to break the supply line. Bazooka tubes are mounted on the Mustangs'

wings and the Yanks are out shooting sky rockets at the Nips. w ater -borne supplies get holes punched in them. Trucks and tr ains are blasted out of this world. A new incurable headac he for the Japs is born . . .flying bazookas.

Nort h Ame rican P-S I Mu sta n g Fig h te r

WORl O'S 'AS TEST ' IGHTU

P ~ A "E

., SPEED

ovu

~2 S

M. P.H .•

, Cf l U NG OV U .Q,ooO Fu r

North Am.erican .t\ d o ti o n Sets the Pace PlAN U THA' MAKE HI ADLINES. •. llu P -5 1 ,lfli.!tQflgfighln" (A .'6fighkr-fxnn brr), ~25 a"dPBJMitdrAl

.IT-6 Iwd SNJ

1c.~a'i combat train(/", N orth .d./IlUU UIl Av iatwll,

bomMr,tAe l ac. Member,A ircraft War pm ll.ctio71 Cowu;il, In"

P-S I MUSTANG

8S

finishing Touch An Ameri can Mustang pilot has latched himself onto t he ta il of a new Nip Navy plane- th e Tcjo. Th e fJ,:antic I ap has pu lled every trick in the book. Finally, in despe ration he racks hi s T ojo into a back -breaking 180 degree vert ical tum. T he

llONDSbought these p!:!nes . WASTE FJ,.'l'S helped ann them . W~"TK P.~P£R.hel ped shi p them . GASOLl:lE f1j~ them • WILL

YOU help delive r th e next squ ad ro n ?

Mustang pi lot ref using to g ive up his advant age. follows. Hal fw ay around th e Musta ng has out-turn ed the T o]o, At the three-quarter mark the l ap has tu rn ed into the gun sights of th e Mustang. T he Ameri can pilot applie s the "finishing touch. "

. ·'Uurri o mc Hall,'· famed wind tunne t at tl:orth American Avia tion whe re en . gineas creale man·m"dc hu rricanes to d,,'·d op and test the sta!>ility alld flight characteristic!; of the <'·5 1 Mustan g.

North ibnel'ican Aviation Sets the Pace PU,NU ' "AT MAleE "UDlINE S . • • the P-5 1 MustaJigfighter(A-36 fighler·bomber). S ·25 a,/d PSj MitchcllboI/lMt", the A T·6 and SNj Tem/ I ecmbat trainer. North Ameri"m Aviation, Inc. Jlcmhcr, A ircraf t iVar Prodlfction CtJff/lcit. Ino:

86

P-51 MUSTANG

Winged Starting in a screaming dive at 8,000 feet this P-51 Mustang pilot is hurl ing his winged javelin at a l ap attillery position. Right now he is travelling so fast that anti-aircraft gun s cann ot even follow him. He is in an

80degree dive. His pull-outwill be at "rhubarb height." Th is is one of the most accurate forms of bombing. The strain on both plane and pilot is terrific. but the P-Sl Mustang can take it like American pilots can dish it out.

No r th American Aviation Sets the Pace PLAN I S tH AT MAKI H IADLI NI S••• the P-51 M ustang jighter (A -36fighter.bt:nnher), B-25 and PBI M itche/l1xJmber, the AT-6 and SNj Texan combat trainer. Nort h American Aviation, Inc. Member, A ircraft War Production Council, Inc.

P-S I MU STANG

87

Thi« Pence ')'olk . Alokes Sense ./ Yo u don't have ro tra nslate the languageofa Mustang's 50 calibre guns or the 75 millimeter cannon talk ofa Mit chell bom ber. T he J aps already unde rstand. So do the Nazis. So le t'S keep talking, Yo u bet you (an help! Thi nk of it this ~r-------

REVOlUTIONA RY

SU ~ER .SP[E O

way. The Bo nds you buy help bui ld these fast -talk ing planes. T h e waste fat you collect hel ps unn "ihcru. \X' astt: paper helps ship them, and gasoline flies the m. Would n' t

you like to saya fewwordsof this kindofvpcace talk," too?

North Amer ican P-Sl MUIt a ng Fight e r

_

WING

SU f _SEAUNG GAS TANKS

SIX $.O-CAI.. MACIlIN£ O!:'N S, t HREE IN EACH WING

fill MUSTANG 15 A ~ nOM 'H! GIIC I/ NO U ~l

1000

' p' ..!' ~ •• ,

. U m,p. h.

~,.

ROMI UNDER EACH WING

C.lling t . 0,000 f • • ,

Ran,. , 200 0 mil.,

North Amel'iean Avi a t i o n Sets the Pace PlANES fH A' MAK( HI ADlI N ES • • . tkB.2S .\1i/eMII bomber. A T·6 T.;:""" (0", 1>(1111'(11"(, , p . st M",/,mg figMff (A·36 fighltr·bcrnkr), and Ihe lJ.2 4 LiWata, />qm/ot:r. No,-ti, A",...ica" A.,jaj;'m,ltu:. ;If"",kt-. A,'emf! War Prwh,cti(m Ce"".il, 1"".

88

P -5 J-1:1 UST~'::IG

Boosting the Harrison radiator into position in a P-SID fuselage. Note the strong straps that would firmly hold the heavy radiator in position.The radiato r had 2.7 square feet of fronta l area and contained a separate section for supercharger cooling. while the oil cooler was fixed forw ard of the coo lant radiator in its own channelled scoop with shutter L EFT

With the radiato r in place and attach ed (this view also shows all the coo ling plumbing required for the P-SI D). workers prepa re to fit the bubble canopy. which is still coat ed with prot ective fil m. Note the clip board outlining electrical 'squawks' on the side of the fuselage BELOW

BUBBLE TQf'

89

provided . The building consisted of a basem en t, main floor, mezzanine and top floor. The weighing system was in the basemen t, whilst th e main floor hou sed th e test sectio n, contro l room , hallways on each side of the test section, the ther modynam ics roo m and accessories roo m . On th e mezzanine were the computing an d furnace rooms. At the top was the laboratory and model shop, consisting of wood wo rking and mach ine sho ps. In operation, the tun nel was quite a co mplex piece of equ ipment. On ce th e model was in place, engineers wou ld make a fina l ru n-thro ugh to ensure everythi ng was fun ctioning for th e test. Powerful mercury vapo ur lamps were turned on whil e indicators were checked to make sure all doors were securely locked. If a door some how opened during a test, the powerpla nt would auto matically shut down . The floors had been vacuum clean ed since du st had to be removed from th e atmosphe re, and very littl e air was taken in from th e outs ide in o rder to keep th e test sectio n as clean as possible. Once th e test sta rted , th e clutch was set for low speed an d the power was turned on. As th e speed increased, there was a rising roar and slight vibration that wou ld fill the building as engi90

P- S I MUSTA N G

ABOVE Mat ing a V-I650-7 t o the firewall. Finished as a complete unit. t he entire engine insta llation was a masterpiece of simplicity. and an engine change could be don e in the field in we ll under 24 hou rs

Mo ment of tru th . Raised on ho ists. a P·51 0 fuselage is prepared fo r mat ing to the wing. Rather amaz ingly. the structure was attached to the wing at o nly fou r po ints OPPOSITE TOP

Alread y fitted with th eir back plates. Hamilto n Standard prop elle rs are guided on e by o ne to the final assemb ly line.As with virt ually every o ther major Mustang comp one nt, the prope llers we re moved via over head lifts. Note t he extremely Sto ut meta l and canvas strap for lifting the heavy unit LEFT

BUBBLE TOP

91

ABOVE A wo rker carefully guides t he Hamilto n Standard pro peller onto t he Me rlin's drive shaft. Note the lightening ho les tha t have bee n dr illed into t he spinne r's back plate

92 - P-S I MUSTANG

Carried on a ro lling rack, Browning .50 cal machine guns are whee led into place for inst allation in a D-mo del's wing. In moving fro m the P-S I B/C to t he P-S ID, an extra two guns were needed to fully outfit the fighter.The basic .50 cal weapo n weighe d 69 Ibs O PPO SI T E TO P

RIG H T Bro wnings in place , with ammunition access panels remov ed to revea l t he neatness of t he installat ion .The P-5 ID/K co uld carry no less t han 1880 .50 cal ro unds, with t he inboard weapo ns having 400 ro unds and t he ce ntre and ou tboard guns 270 ro unds apiece

BUBBLE T0 l:

93

94

P-S I MUSTAN G

Metal underwing pylons eventually replaced earlier Phenolic resin units. Fitted with a SOO-Ib bomb on P-SID-S-NA 4413553, t his pylon had been sten cilled for a maximum 550-lb bomb load when photographed on 20 May 1944.The load limit was later raised to 1000 Ibs LEFT

LEF T At the Web er Showcase and Fixtu re fact o ry in Los Angeles, hund re ds of Musta ng drop tan ks pass through an infrared drying syste m while a female worke r kee ps an eye o n production in this 5 August 1944 pho tograph

RIG HT With a minimum of celebratio n, a wo rker applies a rather crude number 10,000 to identify the 10,000t h Mustang as it rolls off the pro ductio n line

BUBBLE TO P

95

neers carefully monito red the models, grap hs and instrument s to make sure that the recording graph pap er was sm oothly moving th rou gh th e automatic recorders. When th e readings for a particular setting h ad been obtained, the power was sh ut o ff and the engineers began rigging the model for its ne xt test. Wit h the second run, t he grap h would record the effect of t he air stream on the model under new condition s. The test sectio n where the model was placed was a narrow tunnel th roat ope n at both ends, its wooden walls being made of h ighl y polishe d redwood and pierced by ob servation windows on both sides . Through the windows, NAA engineers coul d watch th e model bei ng tested. Special cast steel struts su pported th e mod el on a cen t reline and the stru ts ran down through th e floor, with out touch ing it , and were an ch ored to a structural steel 'I' beam . This, in turn, was supported indirectly by the weigh in g scales thro ugh a series of rods and levers. There were six scales to mea sure the lift, d rag, side force, pitching, rolling and yaw ing mo vement (twi sting force) on the model. An automatic recording system gave a co mplete graph of forces acting on the mode l. The scales measu red t he forces exerted against th e model and tran sm itt ed the data electr ically to the control room. _ --,96 = -- P- SJ MD1"rA N G

A nearly co mpleted Musta ng just o ut of the assemb ly hall is fuelled and se rviced under t he camouflage net ting pr ior to its initial eng ine run and systems chec k ABOVE

Devo id of mark ings except fo r fact ory se rials. Mustangs are read ied for engine runs at Inglewood OPPOSITE TOP

RIGHT P-SID 44-72810rest fires its six Bro wnings into a specially designed stand t hat cou ld be ro lled directly to t he aircraft, wh ich remained in its parked attitude rather than ground crew s having t o go to t he extra work of placing the ta il in an in-fl ight posit io n

BUBBLE TOP

97

ABOVE Wo nde rful facto ry view taken at the NAA plant in Dallas (it was act ually in nearby Grand Prairie , but was usually identified as Dallas). show ing a Texan rea dy for delivery t o the USSR. followed by a Mustang for The Nether-lands. one for the Royal Australian Air Fo rce. a USAAF examp le and. finally. a Musta ng Mk IV destined fo r the RAF

98

P-SI MU STAN G

Parked under the Inglewo od camouflage nett ing, t his F-6D (not e the came ra ports) exhibits t he diffe rent finishe s of aluminum used in the Mustang airfram e.The protective fil m for the bubble cano py is still in place. The weight of an F-6D Mustang increased by approximate ly 100 lbs due t o the installation of t he two camer as and asso ciated fi tti ngs and co ntrols. The aircraft retained its full fighte r ar mame nt, however RIGHT

Using lift a nd d rag data, engineers could take th e results of win d tunn el tests an d det ermin e closely what a com p leted aircraft cou ld do . Wit h ou t th e tu n n el, if it had been necessary to cha nge an act ua l aircra ft an d fIy it to correct each fault or error, the expense and ti me wou ld h ave bee n prohibitive durin g wartime. The tu n n el was a shortcut. NAA te sted out a lam in at ed wooden m odel with a bub ble can opy in the tunn el an d found that suc h a mod ificat ion wou ld be perfectly acceptab le. The disturhed air flowi ng fro m th e bubble did not adve rsely effect th e tail surfaces, but th e removal of the up per portion of th e fuselage did resul t in a loss of keel, and the engineers felt tha t the bu bbl e top Mustang would be even more d irectio nally u nstabl e th an earlier varian ts. P-SIB-I -NA sin 43-1210 2 (the tenth such aircraft) was pulled from the assembly line and moved to the expe rimental sho p, where it was redes igned from the windshield back to accom moda te th e bubbl e canopy and cut -down rea r fuselage. Fuselage forgers were redesigned and bu ilt to crea te th e sleek fuselage, an d test pil ot Bob Ch ilto n pron ounced the new mo dificati on very effective. This lead to two B-models being yanked from th e production lin e (the 20 lst an d 202nd P-SIB-IO-NAs) to be utilised as engi neering test un its for the n ew ve rsion of th e Mustang - th e NA-106, or P-SID. Beside t he b ubble canopy, the new variant wou ld h ave numerous other cha nge s. The cowling was sligh tly revised, as was th e wing structure in order to accommodate tw o ext ra .50 cal Brownin gs and th e lan ding gear geometry was also modified. Th e fuse lage fuel tan k was ins talled in all Ds, and th e V1650-7 powerplant was fitt ed as standard. Th e 'Dash 7', as it was

BUBBLETOP

99

'-

PRODUCTION LINE TO FRONTLINE

NORTH AMERICAN AVIATION

P-SI

MUSTANG

100

P-S 1 MU STA NG

BELOW F-6K 44 -1 1554 has the

RIGHT M ustangs being readied

sighting area for its oblique

for a day's test flying before being

camera checked out in a D allas

de livered to the USAAF. By 1945

hangar (note the sighting mark-

the price of a complete Mustang,

ings painted in black on the upper

including government furnished

surface of t he wing leading edge).

equipment (GFE), had dropped to a remarkable $50.985 - or $ 3.59

This aircraft is fitted with a fo urblade Aeroproducts A·542·A I

per pou nd, w hich compared very

Unimatic propeller which had a

favourably to the Be ll P-63

diameter of I I ft

Kingcobra at $6.74 per pound

ABO VE This is why t he Axis powers co uld not win the war over 130 P·51D Musta ngs are parked in the early morning mist at Inglewood as they wait fo r flight tes ting.American mass production te chniques became the world's most efficient during the war. Even though the Mustang was one of the simplest

war time fighters, the aircraft comp rised over 36.000 parts held togeth er with 25,000 rivets. and these totals did not include 300 GFE items

BUBBLE TO P

10 1

102

P-SI MUSTANG

LEFT An NAA worker hands the Maintenance Inspectio n Reco rd to a USAAF ferry pilot prio r to P-510 -5-NA 44-13962 departi ng its Inglewood birthp lace forever

ABOVE W hile P-S l D production was phasing into the lightweight P-SI H. trialling was still going on in order to find ways of improving the Musta ng's less t han ade quate directional stability. No te that P-5 10 44- 13253 (the first 0 -5NA) has he re been fitted with a meta l rudd er and increase d vertical fin, along with an expe rime ntal do rsal fin. Behind it. P· SI H 44· 64 162 (the th ird H-model) wears an ea rly style vertical tail before t he unit was increased in height. This aircraft is followed by P-SI D· 20-N A 44-6400 I. with a stan dard D-mod el vert ical tail and dorsal fin

BUBBLE TOP

103

commonly known, had its supercharger impelle r gear ratios cha nged, which inc reased take-off power to 1490 h p and fun power (at 8500 ft) to 1590 h p. Gear rali os for the supercharger became 5.802:1 (low speed) and 7.349:1 (h igh spe ed), and although th is modification sligh tly reduced performance at altitudes in excess o f 25,000 ft when compared to the V-1650-3, it sign ifican tly boosted speeds at lower altitude s. Once in the frontline, however, it was not uncommon for the engin es to be in terch ange d, and early mod el Mustangs could be found with 'Dash 7s' wh ile later ones also u tilised V-1650-3 powerplant s. Overhaul lime was determ ined to be 300 hours flying tim e for either variant. Besides some of the earlier aircraft, the elevators had their fabric covering replaced with metal, but the rudder remained fabri c-covered throughout D-model production . Some attention was also paid to improving the P-51D's aileron effectiveness, with seals being attached to the aileron's balan ce strip's lead ing edge. Thi s m odificat ion wor ked very wen , allowing pilo ts' to lessen th e stick forces req uired to manoeuvre the fighter, particularly in combat. The structural integrity o f the ailerons was also improved through the employment of three hinge bearing attachments rather than two . With the add ition o f two extra Browning M2 weapons, the P-51D cou ld tote 1840 rou nds of ammun ition , divid ed int o 400 rounds for each inboard weapon, while the centre and outboard .50s had 260 rounds ap iece. Capable of firing 800 roun ds per minute, th e M2 ha d a muzzle velocity of 28 10 ft per seco nd, with a maximum range of 7200 yards, but the effective comba t ran ge was about 800 yards maximu m . The early P-5 I B/Cs had lots of armament problems since the weapons were installed at a rather extreme side angle to allow feed chutes easy access from the ammun ition trays, but this caused jams due to casings and lin ks becoming en tangled in th e feed belts. Furt he r snags were encountered with the weapon s' oil and grease lubricant, which would often congeal at rarified operatio nal ceilings despite being fitt ed with hea ters (t he latte r were usually only act ua ted near the combat area). These major problems were rectified by repositioning the weapon s and issuing instructions to pilots to turn the heaters on afte r the weapons had been charged. The D-model Mustang was to be the 'shining light' o f NAA's wartime prod uction, th e Inglewood plant alone co nstructing 6502 D-NA figh ters. Th is tally Inclu de d an ea rly o rder for 100 P-5I D-1-NA aircraft to be su pplied una ssembled to Australia, and, oddly, the first four aircraft of this order were des ign ated as Ds, although th ey had th e old sty le buil t-up canopy! The Dallas factory would go on to contribute a furthe r 1600 D-NT Mustangs to t he over all total, a number which included 136 aircraft converted into F-6D photo-recon platforms. The Dall as-buil t P-51 K was similar to the D-model bu t featured an Aeroproducts propeller, and 1500 of these mach ines were also comp leted . By any sta ndard, th e P-5 I D was a resounding production , as well as combat, success. 104

P-SI-MUSTANG

CHAPTER

W

There is a misconception that the Allison-powered Musta ngs were somet hing of a failure in fro ntli ne

ser vice. In th e enviro nment fo r which it wa s des igned (low to medium alti tudes), the A llison

Musta ng was re spected by its adversari es. and the fact that th ese airc raft se rved t hrou gh t he entire war is an indication of th eir

success . W ith t he wind sock sticking out almo st ho riz ontall y. Fig O ff

D W Samson. an Aust ralian from Adelaide. and his grou ndc rew

FRO N T LIN E

prepa re Musta ng IAG43 1 for a mission on 3 June 1943. As can be se en, t he airc raft's paint has weathered and chipped from intense operations . Note also the barre ls for the .50 cal machine guns pr otruding fro m th e cowling

above the pilot 's head, and th e o pe ning cut into t he rear vision panel fo r a cru de , but effective , camera port. Ass-igned to N o 16 Sqn when photographed,AG 4 3 I was converted into a maintenan ce tra ining airfr am e during

October 1943. wit h the serial 422 5M. lt is interes ting to note that the RAF got an ave rage. and amazing. engine life of 1500 hours with the V-1710-39 - three tim es th e life of th e average Merlin. Also , th e Brit ish did away with th e automatic bo o st control. resulting in a grea t increase in lowe r level perfo rmance with no apparent ill effects - operating at full t hro ttle (72 in Hg) at se a level fo r over 20 minut es wit hou t damaging t he engine

FRO N TLI NE

105

.. .

4 . .,

..... ..

.

... .

.-

«~

.. .-..

.... . . - - -.I • ,; ...

.

~

:

,.

106

P-SI MUSTANG

..

Mustang I in its element down low and banking to utilise the F.24 camera mo unte d behind the pilot.W ith his aircraft finished in D-Day markings, t he pilot is reco rding a stream of Allied tank s moving through th e village of Conde-sure-Noireau following the successful Allied invasio n (and photographed from another Mustang 1).Tac-reco n missions were called 'Rangers', and whilst o ne pilot would take photos, another would act as escort (weaver'). keeping a loo ko ut for Ge rman fighters while t he othe r pilot concent rated o n taking the photos LEFT

ABOVE Two No 2 Sqn Mustangs - AG550 is nearest the camera and is an NA-73 from th e first batch of RAF Musta ngs, while AM112 is an NA-83 fro m the second batch.AG5S0 crash ed into a hill near Kimmeridge. Do rset, while flying in fog on 26 May 1943 and AM112 was damaged by flak on J August 1944 and crash-landed at forward airfield B8. No 26 Squadron at Garwlck, in Sussex, began receiving Mustang Is for ope rationa l tr ials during Januar y 1942, completing an inten sive t wo-week work-up at Weston Zoyland. In

March 194 2 No 24 1 Sqn re ceived Mustangs, followed by No s 16, 268 and 613 Sqns in April. No 2 Sqn at Sawbrid geworth also rece ived Mustang Is in April 1942, co mmencing opera tions in July. The Mustangs were a mar ked improvement over the squadro ns previous equipment, namely the ungainly Lysander and outclas sed Tomahawk

FRONTLI NE

107

, ..

",,'

..

, .

., .,• ,,:

r: .'

','

\.~

.'

..

""

. .-. e •

':

ABOVE A rather pastoral view of tac-r econ Mustangs in their element at a forward airfield follow -

ing the invasion of France.T he

pilots ar e re laxing between missions . enjoying a game of cards. reading and w riting letters hom e. Afte r evaluating the type,Wg Cdr Ian Ca mpbe ll-O rde mad th e following co mmen ts on 5 May 1942 abo ut the aircraft 's equipment

requ irements for operations from fo rw ard bases ;'It is thought that little extra equip me nt wou ld be required for operating the Musta ng fro m a forw ar d base .

108

P-S I MU STANG

Th e radiator. howeve r. picks up mud easily on a mudd y aero-

dro me . and water unde r pr essure is req uired for rem oving it succes sfully. It has the ben efit of having th ree good methods of sta rting - by external batte ry. by internal batte ry and by hand iner t ia. It must be noted that t he size o f t he fo rward base must be greate r t han th e minimum neces sary for contemporary types'

BEL OW During June 1943 Army Co-operation Command was disestablished and the Mustang squadrons placed under the umbrella off the 2nd Tactical Air Force or RAF Fighter Com mand. The NA-9 1 was an improved Musta ng I fitted with the powe rful punch of four 20 mm cannon, and the British ordered 150 aircraft as the Mustang Mk IA - the type eventua lly equipped Nos 2, 63. 168. 170, 17 1 and 268 Sqns. However, with the attac k on Pearl Harbor on 7 Decemb er 1941,the Ame rican govern ment commandeered 55 of the aircraft, resulting in only 92 cannonarmed Mustang lAs reaching Britain for frontline service. Here, Mustang IA FD472 receives field maintenance at a forwa rd airstrip during the Allied invasion of France. Note how the D-Day invasion st ripes have been applied

in a very neat manne r, and even exte nd onto the fairings for the cannon s.The 20 mm cannon was ideal for the tactica l reconnaissance mission since it cou ld easily destr oy or damage ar mo ured targets. Also, the weapon was in wide use on other RAF aircraft, which meant that serviceability in the field was quite goo d. Due to the fact that the initial delivery quantities were re latively small, and given the type's hard use and co mbat losses, it is not surprising that the numbe rs of in-se rvice Allison Musta ngs had rapidly declined by late I944.At first it was thought that the Me rlinpower ed Mustang Mk III could be incorpo rated into the units with Mk Is, but the re wer e too many ope ratio nal differences bet ween the two types. Not wanting to lose the long-range tac-recon coverage supplied by the Allison

Mustangs, the surviving Musta ng squadron s were str ipped down to opera te with bare esse ntials from primitive airfields prio r to the invasion of France.A Mustang squadron nucle us was built around the command ing officer. adjutant, pilots. aircraft and a mobile airfield team , which was respo nsible for maintaining and fuelling the aircraft, along wit h providing for the needs of squadro n perso nnel.The hardpre ssed Mustangs provided sterling se rvice before, during and afte r t he invasion. FD472 was serving with No 268 Sqn when it was str uck off charge on 30 September 1944, probab ly as the result of battle damage

FRONTLINE

109

~_-..:2_~

_

-, ABOVE Num e rou s co ats of paint and ext reme ly heavy wea thering

at Langley Field,Virginia, w here it was used fo r high-spe ed fli ght

disguise the impo rtance of t his

t est ing.The airc raft had bee n schedu led fo r de livery in Febr uary/March 194 1, and Gen Hap Arnold wo uld late r co mment, 'That we did not have it (the Musta ng) sooner was t he Air Fo rce's own fault' .W hen pho tog raphed, '0 38 was in storage at Free man Field, Indiana, fo r a pro posed natio nal air muse um. The aircraft was eventuall y sto red at the Smithsonian's Silver Hill facility until transfer red to the Experimental Aircra ft Assoc iat ion in t he late I970 s. Here, it was magnificent ly restored by Dar rell Skur ich and flow n for several years , until placed on display in th e EAA Museum

aircra ft - XP·S 1 USAAC sin 41-038.As part of the origi nal con tract with the British, the fourth and te nth NA-73 Musta ng Is were take n from the initial production bat ch and supp lied to the Army Air Corps for fur th er test ing to see jf the aircraft warranted pro ductio n. Ro ber t Chilton took XP-SI '038 aloft for the first time on 20 May 1941 but. fo r vario us reaso ns, th e fight er did not get to Wright Field for exten sive t est ing unti l 24 August 1941 , followed by XP· S 1 USAAC sin 41· 039 o n 16 December. Mo st of the testing wa s done with '038. as '039 suffered from a numb er of pro blem s. and th e former was even t ually t ransfer red t o NACA

1 10

P· S 1 MUS TANG

O P P OS IT E TO P Filt hy, and decided ly t ired lo ok ing in appe arance, a 27th Fight e r Bo mbe r G rou p (FBG) A· 36A takes a brea k fo r a snap shot with its groundcrew at Gela. Sicily. Note bombs under t he wing and the barrels of t he .SO cal machine guns pro truding fro m t he lower co wling.The lat t er also records 150 co mbat missio ns (98 dive-bom bing, 42 strafi ng and te n ar med reccn). while the spinner has been painted red and a blue surround had been rec en tly add ed to the nat io nal insignia. Individual aircraft lett er 'A' was applied direct ly over t he aircraft 's se rial.Th e odd loo king splotch atop the fuselage immediat ely behind the canopy was a poison gas detector patch . Operating from forward airfields, A-36As inflicted t re mendo us damage on fron tline Axis fo rces

An A-36A pilot perform s a low pull out after blasting a target during a statesi de training exercise. Ext ra stre ngthening was adde d to the wing and dive brake area to enable the two -foot wide bra kes to open during a dive, effectively reducing the airspeed to around 390 mph.The 27th FBG found that the aircraft was very effective in the dive-bombing ro le when the dive was ent ered at 90 0 from an altitude of aro und 8000 ft - during these dive atta cks, up to 20 A-36As would hit an enemy ta rget. In some vintage Nor th American adver tisements, the A-36A was called the 'Invade r'. but this was never an offi cial name. Lt Rober t Walsh of the 27th FBG. stated .'why don't we call them Invaders. since we're always invading places!' The name certai nly st uck with the pilots that were flying the aircraft. Comm anded by Lt Col John Ste venson, the 27th FBG ente red combat by blasting the island of Pantelleria (A. 36As new 1000 missions during 35 days) dur ing April 1943.The Twelft h Air Force fielded t he 27th and 86th FBGs, the latter being the first to go overseas in March 1943 LEFT

FRON TL IN E

II I

, 112

P-S I MUSTANG

,

..

.."

., .

Not an overly photographed aircraft (probab ly because most of them were assigned to remote and hotly contes te d fo rward comb at areas). this fine aerial port rait of A-36AOPPO SITE TOP

I-N A USAAF sin 4 2-83726 was

taken at a states ide tr aining base (vvaycross . in Georgia). indicated by the code painted on the verti cal tail. Note the heavy exhau st staining from t he Allison V-171087, denoting that the engine had been ope rating at high power settings.The dive brakes made the repos itioning of the pito t tube necess ary, and this unit was installed on the right oute r wing panel. Besides the two .50 cals in the nose . the .30 cal wing guns were replaced with four .50 cals. giving the aircraft a ver y heavy punch. Finally, the bomb racks wer e installed close r to the gear legs in order to utilise as much struct ural strengt h as possible. A-36A pilots wo uld go on to accou nt fo r 84 enemy aircraft destroyed during ae rial com bat

Its propeller churning up dirt, P-S1-2-NA

OPPOSITE LEFT

USAAF sin 41-37367 is guided

into a well-protected revetment on a field near the Anzio beach by its grou ndcrew during April 1944.The bottom of the revet ment's blast wall appear s to have been formed empty(?!) Italian wine barrels , with sand bags piled on top. Named Betty Jean, the Mustang is in very worn condition . with only part of the American flag remaining visible on the rudder.The national insignia on the fuselage has had its yell ow identifier painted over in blue. and white bars have also been added . obscuri ng the se rial which has been crudely repeated on the vertical fi n

ABOVE P-SIAs equipped only three USAAF units - the 3 1Ith and 23rd FGs and the Ist Air Commandos (AC).The latter outfit adorn ed their P-51As with the distinctive five white str ipes seen around the fuselages of the se aircraft.Although operating in the rough conditions of the China Burma India (CBI)Theat re, the Mustangs. and the ir Allison engines, proved to be extreme ly rugged. Lead aircraft carries t he name Mrs.Virginia. and note the heavy exhaust staining on both fighte rs. Forward portio ns of the spinners were left in natura l meta l.Seen near the Chin Hills. the second Musta ng is be ing flown by Col Phil Cochran. who later became t he character 'Flip Cor kran' in the popular com ic st rip Terry and the Pirates

FRONT LIN E

113

TOP USAAF sin 43-6174 was originally built as one of 155

P-S IA·l O-NAs, but was con verted to an F-6B photo-rec on platform .W he n pho tographe d at

t he name Jeanie under th e w indshield, and t he crude ly app lied wh ite identi ficat ion bands o n t he nose and wing.The D-Day mar kings under t he fuselage are

Le Molay, France, duri ng A ugust

almost ob literated on this air-

1944, t he aircraft (fitted wit h an

craft, altho ugh those on t he F-6B

English-designed Malcol m ho od

in the backgr ound are sti ll intact

bubble canopy) was assigned to th e I07th Tact ical Recon naissance Squa dro n (T RS), 67t h Tact ical Reco nnaissance Grou p (T RG). Note th e mission mar kers in t he form of cameras o n t he cowling,

114

P-S I MUSTANG

ABOVE Getting t he Mustangs to

Britain was a major o peratio n in itself.Aircraft being shipped by sea stood t he co nsiderable chance of having t heir transpo rts

torpedoed by U-bo ats. Minus t heir t ails and carefully cocooned against t he salt air and elements, these P·S IBs were photographed o n 18 Apr il 1944 at Filt o n in Brita in. In the background can be seen furt her B-mo dels in bare metal t hat have had their protect ive covering stripped off and are in t he process of being prepared fo r flight.Also no te t he var ious Do uglas A-20 Havocs squee zed in amo ngst the Mustan gs, th ese aircraft having also arr ived by ship

ABOVE P-5 1B-5-NA assigned to t he 368 th FS. 3S9t h FG.The spinner and nose band of this aircraft have been painted in green squadron colou rs. Note the Malco lm hood, single victo ry marking under the windshield and pe rsonal insignia of an Indian girl with a bow and arrow

ABOVE Flying Fo rt ress crews fro m t he 40 Ist BG (many of whom are wearing jackets with their aircraft 's name painted on the backs) check over P-51B-INA USAAF sin 43- 12172. which landed at their Deen eth o rpe base o n 27 Decembe r 194 3.Assigned to the 353rd FS, the aircraft has had the white identificatio n stripes roughly applied. In orde r to distinguish the aircraft from the Bf 109, the spinner was painted white and a similar colo ured band 12 inches wide applied directly behind it.Anoth er 12-inch band was applied arou nd t he vertical and ho rizontal tails. whilst and IS-inch bands were applied over and under th e wing near t he root. Being painted in the fi eld, t hese dimensions often varied.The verti cal tail band was discontinu ed or re moved fro m camouflaged aircraft from 23 March 1944

FRON T LIN E

115

Rural sce ne o f a 48 7t h FS, 352nd FG Mustan g rece iving in-depth mainte nance . Since the re is a so ldier with a rifle sitt ing beh ind a t ree immediate ly be hind the nat ional insignia, t he aircraft was probab ly pho tog rap hed at a forward field BELOW

I i~

P-S I MUSTANG

TOP Few photographs better

the Rhine and the aircraft is being

ABOVE Cl assic Mustang belly

express the P-51D 's master y

serviced at Y~ 74 , near Frankfurt,

over the once-vaunted Luftw affe

o n 2 April 1945

landing. P-5 ID-I O-NA USAAF sin 44-14 315 of the 383rd FS. 364th

than this view of P-51D -20-N A

FG is seen being examined at

USAAF44-63780 of th e 3S6th

H onningto n on 18 June 1945.

FS, 354th FG . parked next to

Th e individual aircraft letter is

burned-out Fw 1900 vv k-Nr

carr ied in a black circle on the

2 109 17 (not e the Reich D efence

ver tical tail

bands painted on the rear fuselage). Mustangs from this unit were the first to arrive east of

FRONTLI NE

117

RIGHT With cow ling, landing

gear and

J

I O-gal long-range drop

tanks scattered in trai l, P· S I 0-1 5-

NA USAAF sin 44-15516 Danny Bay 2nd of the 350th FS. 353 rd FG rests on it s belly following a ground loop on take-off while other M ustangs launch for mission to Germany on 29 December 1944

118

P-5 1 MOSTA N G

a

Some of t he bes t Mustang photographs to come o ut of Wo rld Wa r 2 we re taking during one photo session con ducted from a 91st BG Flying Fo rt ress. Seen on I I July 1944. the Mustangs we re fro m the 375m FS, 36 1st FG, ou t of Bottisham, Essex. Lead Musta ng is P-5 1D USAAF sin 44- 134 10 Lou IV. flown by gro up comm anding officer Col To m Christian. who was killed in action in th e aircraft o n 12 August. First Lt Urban Drew was flying 44- 13926 (destroyed LEFT

o n 9 August 1944 while being flown by Lt Don Dellinger) instead of his usual Detroit Miss (Drew was the Gro up's thirdranking ace) . while Lt Bruce Rowlett was in 44-13568 Sky Bouncer and Lt Francis Glanker was pilot ing P-5IB 42- 1068 11. The Mustangs uppe r surfaces were given a hasty co at of O live Drab when it was th ought the aircraft wo uld be immediately deploying to fo rwa rd airfields in France in the wake D-Day

ABOVE Sky Bouncer breaks away fro m the 9 1st BG Flying Fortress, illust rating the lowe r surface D-Day stripes and d rop tanks to advantage

FRO NT LIN E

119

120

P-S I MUSTAN G

Parked on pierced stee l planking,Joh n Meyer's PETIE 2nd rests between missions .The aircraft wears th e 'HO' codes of the 487th FS and the pilot 's impr essive sco re board - when Meyer foun d o ut th at the swastikas o n his aircraft did no t stan d out in the air as well and the crosses carr ied by so me of the other squad ro n Mustangs, he ordered his crew chief to put th ick black outlines around the kill mar kings so that the Germans would rec ognise him in t he air LEFT

The pilot of P·SI D USAAF sin 44· 140 34 'SY.]' died wh en his 384th FS,3 64th FG Mustang cr ashe d on landi ng and burst into flames at Ho nningto n on 30 July 1944 OPPOSITE BELOW

Mustangs o n parade . Pho tographed dur ing a victory ce lebration on 7 June 1945, th is view shows the unstopp able force of P-S Is in Eur ope .Taken at th e 78th FG's home field at Duxfo rd, each row co mprised an entire squadron .The 83 rd FS fills the middle with their Dallas-built P-S IKs, w hile th e ot her two units flew D-mo de ls BELOW

FRONTLI N E

121

A BO V E Ce rtainly one of the mos t attractive Mustangs. Big Beautiful Doll (P-S 1D-20- NA

USAAF sin 44-72 2 18) was the personal mount of Col Jo hn Landers. commanding officer of the 78th FG. Landers was an ace in bo th the Pacific and Euro pe the atres

122

P- S 1 MUSTANG

W ith bare meta l Mus-tangs servi ng as a backdrop. Miao workers pull a ten-to n roller over the ro ugh runway surface at Lao hwangplng airfield in China BELOW

FRONTLI N E

123

124

P·SI MUSTANG

Col Wi lliam Banks leads a colou rfully appointed pack of Mustangs from the 348t h FG. His own aircra ft was P-SIK-IO-NT USAAF sin 44-1 2073 SUNSHINE VII OPPO SITE T OP

L EFT The Me rlin engine of a 3rd AC Musta ng is run up prior to mainte nance at an occ upied Japanese airfield following VJ-Day. As we ll as th e black fuselage bands , the unit's aircraft also carried six black wing bands. Part of the occupation fo rces, the 3rd AC operated out of Chitose

Two days after the atomic bombings, t hese Mustangs stand neatly parked at their Pacific airst rip - waiting for a mission in a war that had co me to a sudden, and startling, conclusion ABOVE

FRONTL INE

125

CHAPTER

126

rn MUSTANG MEN

P-S I MU STANG

LEFT Maj David L 'Tex' Hill .A ~2 jacket firmly but toned up, prepar es fo r a mission in his 75th F5, 23rd FG P-51 B so me w he re in Ch ina. Hill originally entered th e Navy du ring 1938 and received his flight training at NAS Pensaco la. go ing o n t o fly w ith VT3 aboard the USS Saratoga and VS ~4 1 aboard t he USS Ranger. Resign ing his co mmission durin g

the summ er of 1941 . Lt (jg) Hill jo ine d the American Voluntee r G ro up (AVG) in Ch ina, where he went o n to de stroy a t otal o f 1 23/~ japanese aircraft before it disband ed o n 4 July 1942. Hill decided to stay in Chin a, accepting a commiss ion as a major w ith the USAAF and then going o n to activa te th e 75th FS. where he dest roye d four more japanese fighte rs. In December 1942 he returned to the USA, but was posted back to C hina the following year. where he assumed command of th e 23rd FG and des t roye d two more en em y fighte rs. Returning to Ame rica o nce again, Hill bec ame CO of t he 412 th FG with Bell YP-59s (later P-80s) - t he USAAFs first jet unit. He se parated fro m the service in 194 5 and joined t he Texas Air Nat io nal Gu ar d

ABOVE His face marred from ho urs o f wearing goggles, a smiling 2nd Lt Robert G Young,jr.

enjoys a smoke in the cockpit of his P-S l D after return ing fro m a bo m ber escor t missio n to Be rlin. The flag placard aro und his nec k ide nt ifies the pilot as an Ame r-ican . wh ile th e reverse side carried an inscription in Russian fur t her co nfir ming his sta tus as an USAAF flyer

MUSTANG MEN

127

Majo r Walker M 'Bud' Mahurin. with his elaborately marked P-51D-15-NA USAAF sin 44- 14978 " THE CHI EF", was part of the 3rd FG, 3rd FS, in th e Philippines. Mahurin ach ieved the majority of his ae rial victories in Euro pe wh ile flyi ng Thunderbo lts, but o n 14 Januar y 1945 he sho t down a Japanese 'D inah' w hile piloting t his aircraft. During t he Ko rean W ar. he was cred ited w ith 3 1/2 MiG 15s de st royed before be ing sho t down and ta ken prison e r

RIGHT Lt Jo hn C 'W hips' Meyer in the cockpit of 487 th FS P-SID-15 -NA USAAF sin 44- 15041 'HO-M' PETIE 3rd on 6 January 1945. w he n he was, w it h 37 1/2 victories (24 in t he air. 13 1/2 o n th e gro und ). the top-ranking ace in the Eighth Air Fo rce. Staying in t he air fo rce afte r W orld W ar 2, Meye r went o n to co mmand t he Str at egic Air Com mand befo re re t iring from the USAF as a General o n I August 1974. He died of a hea rt at ta ck t he followi ng year wh ile jogging on a Los Ange les beach

BELOW

--.-__a~_ _ fl

..,,,-,.,.

S r~·"

128

P-51 MU STA N G

MUSTAN G MEN

129

ABOVE Maj Jo hn Colem an 'Pappy' Herbst in the coc kpit of 74t h FS. 23rd FG P-S IB-7-N A USAAF sin 43-7060 Tommy's Dod in the CBI.The very weathered condi tion of th e Olive Drab and Ne ut ral G rey camouflage is no teworthy, as are the caps placed over t he o pen ings for the .50 cal Brow ning machine guns. Herb st en de d t he war with 18 1/3 Japanese aircraft destroye d, and like several othe r Ame rican aces, he was killed in a po stw ar jet cras h, perishing in P·80A-I -LO USAAF sin 44· 85053 nea r San D iego, Califo rn ia.The w hite cross on the fuselage let groundcrews know t hat th e aircraft was equip ped with the fuse lage fuel tank

130

P-51 MUS TANG

OPPOSITE TOP A rath er appre-

hensive lo o king Royal Canadian Air Force Musta ng I pilot (from probably either Nos 400 or 4 J 4 Sqns) waits between missions as ground crewmen remove the F.24 aerial camera. Down low, the Mustang I was an exce llent armed pho to -recon platform, and Wg Cdr Pete r Dudieen. a form er squadron comman der of an Ar my Co -Ope ration unit , made the following co mme nts o n 3 1 May 1943;'The lo ng range o f t his aircraft made it an ex ce llent tactical reconnaissa nce aircraft and its arma ment made it effective against mo st ground targets.As thei r o perations progressed, t hey swung more and more to offensive reconnaissance and began t o

take advantage of targe ts of opportu nity until t he o peration finally develop ed into a strategic effort against groun d o bjectives such as railway locomotives, canal barges, heavy motor transport vehicles and aircraft on the grou nd'.The usefulness of the Mustang I was suc h t hat less than 100 remained operational wit h t he RAF at t he end of t he war

RIGHT Maj Richard ETurner

with 356t h F5 P-5 1B U5AAF sin 43- 12434 'AJ-T' SHORT-FUSE

SALLEE. Turner received his pilot 's w ings on 29 Sept ember 1942 at Luke Field.A rizona. and ente red the combat arena with the 20 th FG. before being tra nsferre d to

th e 356 th F5, 354th FG during January 1943. H e destroyed I I aircraft in combat and damaged eight others , and was also credited with the destruction of two V I 'buzz bombs'. D uring the Korean War.Turner flew 13 combat missions with the 4th FIW H e died on 15 N ovember 1986 of complications arising from the onset of A lzheimer 's disease

MU STANG MEN

131

132

P-S I MUSTANG

LEFT A displeased looking Is Lt. Wi lliam T W hisne r is seen with his 487th FS P-51 B-S-NA USAAF sIn 42-106449 'HO -W ' Princess EUZABETH. Whi sner rece ived his wings on 16 February 1943 at Napier Field,Alabama, and was trans ferr ed to the 352nd FG a few days late r.Achieving his first victory in a P-47D,W hisne r was soon flyi ng the Mustang following the transitio n of his to the NAA fighter. He went on to achieve a tota l of 15 1/2 victories, all Luftwaffe fighte rs, and two probables.Whis ner also saw comba t during the Korean War, shooting down 5 1/2 MiG ISs and damaging six more.The reason fo r the unhappy look! W hisner's Mustang had been chosen to receive the name Princess ELIZABETH to coincide with the real princess's visit to his Bodney base, and the fighter pilot did not like the idea, nor the attendant press publicity. The valiant figh te r ace died following an alle rgic react io n to a yellow jacket sting on 2 1 July 1989 in Alexandria, Louisiana

During the D-Day invasions, USAAF and Commonwealth Mustangs racked up countless missions against the e nemy.The fact that thes e aircraft cou ld be rapidly turned around was due to the unwavering dedication of the ground crews - often wo rking in the open in harsh weath er. These RAF personnel are see n 'bombing up' a Musta ng III. Note the crudely painted D-Day identification stripes LEFT

ABOVE Capt Joh n Francis 'Smiling Jack' Thorne ll poses with crew chief SSgt G A Mclndoo and P-S IB- IS-NA USAAF sin 42-106872 'PE-T' of the 328 th FS. The pilot used this very aircraft to destroy three Bf 109s on 8 May 1944 near Nienburg. Tho rne ll finished the war with 17.25 aerial victories and two damaged. Note the additional rear view mirro r that helped co mpensate for the B-mode l's lack of rearward visibility

MUSTAN G MEN

133

Charis mat ic Co l Donald James Math ew 'Co l Don ' Blakeslee in t he cockpit of a P·S ID Mustang. Blakeslee had a lo ng military caree r, join ing the Army Reserves in 1938, w here he served as a 2nd lieute nant in the infant ry. Honou rably discharge d in 1940, he joined the Royal Cana dian Air Fo rce and arrived in Brita in du ring May 1941. Blakeslee serve d with No s 401 and 133 Sqns flying Spitfire VBs, destroying or damaging 13 Luftwaffe aircraft. He ente red the USAAF as a Captain on 29 September 1942, init ially flying Thunderbolt s. Blakeslee rapidly rose t hro ugh . t he ranks beca use of his natural combat lead ership, and he was so impressed with the Musta ng that he argued, successf ully, that t he 4th FG sho uld re place its P-47s with P-51s. His final ta lly was 14.5 dest royed, t hree probables and II damaged - an, impr essive reco rd fo r a high-ran king pilot w ho had to devote much o f his time t o adm inist rat ive duties

134

P-SI MUSTANG-

-

-

ABOVE Lt Robe rt Jo hn Goebel in th e cockp it of his 30Bth FS

P-51 D-5-NA USAAF sin 4413300 'HL-D' Flying Dutchman.

and Ds, and he ended the war with I I confirmed aerial victo ries and o ne pro bable

Receiving his wings o n 24 May 1943. Goebe l went on to fly Airaco bras in t he Canal Zone , before being t ransfer red to th e 3 1st FG o n I Apr il 1944. Goe bel sco red all his victo ries wit h th e 308th while flying a mixture of Bs

MUSTANG MEN

135

APPEN DICES

MUSTANG VARIANTS

A- 36A -NA

NA·71X

Ha ndbuilt prototype with civil regist ratio n NXI9998 (c/n 73-3097) for British requirement. Una rm ed wit h highly pol ished natu ral meta l finish, pow ered by A llison V- r 710-

P-51A optimised for gro und attack.A ircraft retained machine gun a rmame nt but had dive brakes mo unted above and be low wing.Allison V- 1710/ 1325 hp. Underwing racks co uld car ry 500- lb bomb s. Delivered in Ol ive Drab and Ne ut ral Gr ey camouflage.

30 of I 150 hp. Heavily dama ge d on early t est flight, re built and flight testing continued . Final fate of t his aircraft is uncertain, pe rha ps sc rapped o r don ated to t rade scho o l. XP-SI -NA

XP- 5IB-NA

Two P-51-NAs (4 r-37352, 4 1.3742 1) rebu ilt with Me rlin V- 1650-3/ 1380 hp engines . Many othe r det ail mo dificat ions made to areas such as radiat or, cow ling a nd aileron s. O riginally redesig nat ed XP-78 · NA before switching t o

USAAF acquire d tw o ear ly pro duct io n Mk Is (c1n 73310 f and 73-3107) fo r t est ing t o see if th e aircraft had combat poten t ial for the Army. Had carried RAF se rials AG348 and AG3 54 , assigned USAAC se rials 41-038 a nd 41-039 . Initially flow n in nat ur al metal test ing, aircraft wen t t hro ugh several paint sch em es. Pow ered by V- I? I039 . O ne surv ives with EAA Museum.

XP·51 B. O live Drab / Neutra l G rey camo uflage. P-5IB·NA

Total of 1988 B-models constructed, of wh ich 71 B- rO-NA we re co nverted to F-6C- NAs. Early ve rsion po wered with V-1650 -3/1380 hp. Four Browning machine guns in wing. Later ve rsions had V 1650-7 .550 B-5s became B-7s with addition of fuselage fuel tank . Underwi ng racks held drop ta nks, bombs. Fuselage tank retrofitt ed to ear lier aircr aft.

P-51-NA

Similar to Mk I, 150 built with four 20 mm ca nno n in wing and wit h American sty le inst r ume nts, radios a nd con tro ls re placing British it e ms. C a rr ying cons t r uct ion

Delivere d in O live Dra b/Neutral Gr ey untilAAF edict eliminat ed camo uflage.

numbers 9 J - J 1981 through 9 1-12 130, aircraft we re given RAF se rials FD418 t hrough FD59 7. 57 we re converted

P-5IC-NT

to P-5 I-I-NA standards (lat e r F-6A-NA) an d carr ied two K.24 cameras (se rials 41 -37320 throug h 41- 37339;

at t he Dallas,Texas, plant.Total of 1750 Cs com plete d, including 20 conve rt ed to F-6C -NT. C- I powe red with V1650-3, but remaining 1400 aircra ft carr ied mo re powerf ul

Basically ide nt ical t o B excep t for the fact t hat it was built

4 1-37352 th rou gh 41-37366; 4 1-373 68 thro ugh 41373 71; 41 -374 12 th roug h 4 1-37429. O ne airc raft (4 137426/ FD52 4) was t ransfe rred t o US Navy as BuN o

·7 .

57987. Most aircraft were delive re d in RAF sty le camou -

XP·5ID·NA

flage o r US Olive Dr ab/N e utral Gr ey.

Con version of tw o P-5 1B-1Os (42- 106539, 42- 106540) with cut-do wn rea r fuselage and bubble canopy. Many detail

P-5IA-NA

refine me nts. Ol ive D ra b/Neutral Grey.

Similar t o P-51-NA but wing canno n re placed with fo ur .50 cal Brow nings. AllisonV- 1710-81 / 1200 hp.Two underwing

P-SID-N A

pylo ns for bo mbs or drop ta nks. 50 transfer red t o RAF t o re place aircraft kept by Ar my fo r P-51-I- NA conversion,

Produ ct ion bub ble t o p Mustang. Fo ur P-51 D-I-NAs complet ed with o riginal built-up canopy.Tota l of 6502 Ds built

and 35 later co nverted t o F-6B-NA. Production stopped at P-5 IA-10 in o rder t o change line over to Merlin powe r.

at Inglewood . Dorsal fin added after prod uct io n comme nced to co mpe nsate fo r loss of keel surface after

_ _-1

36

-- -

removal of to p rear fuselage. 1454 P·5 1D·NT built at Dallas. Many refinement modifications introd uced th roughout producti on. D-24-NA had two sets of rocket stub launchers under each wing panel.Six .50 cal Browning guns. Dallas delivered 135 F-6D-20-NT /-25·NT tac-recon variants. Most de livere d in natural metal finish.

ROYAL AIR FORCE MUSTANG VARIANTS Mk l

620 built, te n transfe rred to Soviets, two to the USAAF. Allison V- 17 10·39/ 1150 hp. Four .50 cal guns in wing. two .30 cal guns in lower no se.

TP ·5ID

MklA

Ten Ds modified for dual control training and extensi ve wo rk carried out in the cockpit area fo r pro vision of a second seat and full instrument panel. Part of rear fuselage cut away to make mo re room for secon d seat (first conversion used standard cockpit space and regular canopy) and a larger, longer canopy was fitt ed.After the war, furth er TPs (designated TF by th is time) were built from random alrframes by Temco in Dallas.

Same as Mk I but with four 20 mm canno n in wing. Part of o rde r kept by USAAF.

P·5IE

O riginal designation for Dallas-built D but dro pped in favour of D·NI. XP· 5IB

Two built with 1675 hp Rolls-Royce RM.14.5M Merlin (dn 105-2593 1 to -25932) with five-blade Rotol pro pellers which gave unstable flight characteristics. O ne to RAF.

Mkll

50 aircraft similar to P-5 1A. Mklll

852 aircraft. so me transferred to RAAF and USAAF. Similar to P-SIBle. Mk IV/IVA

Similar to P·S ID/K. MkX

Fou r Mk Is (AL963.AL97S.AM203,AM208) co nverted with Rolls-Royce Merlin 61 o r 6S engines with four-blade props. different radiators. etc fo r testing.

P·5I K·NT

Same as P-51D-NT but built with Aerop ro d ucts pro pelle r instead of Hamilto n Standard unit.To tal o f 1500 Ks built. including 163 as F·6K-NTs; 594 transferre d to RAF as Mustang tV.W ith the K· IO-NT. underw ing roc ket stub s for four 5 in rockets added. P·5IM·NT

Dallas-bu ilt version of the P-S ID-30· NT with V- I650-9A engine. O ne co mplete d but rema ining o rde r for 1628 cancelled with en d of war.

APPENDICI ES

137

u

~

~\ All drawings on this page are of an A-36A. and are

~

to 1/72nd scale

0

~

l

-

OJ

-,

~

•

-

\/ \ fir--

l-

~

I

-,

•

I", I

I

'\.ai

I

r

Ir-k

;J,

.>.

Ir--'-'jL-

).... ~

l

I---

.

I

01' I---c

••

~ 138

P,5 1 MUSTANG

I

~

~

0_

I

~

/

~

0

-...:

I~~

<,

''.0;:'

1

I

[110111111000]] ![~.j

I

~

tJ

1-=-=

L

-

•

i~~~D DOi IIO il

0

- '---

m>-

~ I

>.l=<

~I

0

I-- f--

fr-

"'!..-

_

---- --, ~

c::..

Mustang Mk I

o

o

v Mustang Mk IA

o

Mu stang Mk IA ~

0

P-SIBNA (Malcolm hood) r-

r:

rr

o

~

~

r-

'--- '

0

~

P-SIC- IO-NT s:

0

0 ~.

/ ~

F-6D

APPENDICIE S

139

o

+_

•••J •••!.•.• ~. __

:

o

~ CJ l

o

i f

i

- 1" .

I

I

.. '_. ~ _ .• ::1 Ii

---..~ .

., ...;. .... p. ~ .....:...

.., . ~ i·· · I ... . ,

i

·_.j·:~~:9 - . -~--

-1

"

'~"

" f

!

c

--t __

All drawings on this page are o f a P-51 020- N A. and are to JIl 2nd scale

!

...

;,

n I I '- /

_ _ _ 140

~-51

MUSTANG

P-51 D-20-NA

P-51 B-15-NA (Malcolm hood)

P-51 D-20-NA

P-51 B-1 O-NA

P-51 D-5-NA

o

'0

P-51K-5-NT

-

:& P P E N D I C I E~

14 ~

NAA MUSTANG MODE L DESIGNATIONS Designat io n Military Seria ls

NAA

M U STA N G SER IAL NUMBERS XP-5 1-NA

41-038 and -039 4 1-37320 to -37469 43-6003 to -6 102 43-6 103 to -6157

NA-73X

NA-73X

none (civil NX19998)

P-5 1-NA P-5 IA-I-NA

NA-73

Mustang I XP-5 1

AG345 to AG664 4 1-038 and 039

P-5 1A-5-NA P-5IA-10-NA

Mustang I

Al 9S8 t o Al999. AM100 to AM257. API64 to AP263

XP-5 IB-NA P-5 IB- I-NA

P-51

41-37320 to 37469 . FDil S to

P-5I B-5-N A

NA-97 NA-9 9

A-36A P-5 IA

FD587 42-83663 t o 84 162 43-6003 to 6312

NA- IOI

XP-5 18 P-518 - 1 P-51C- 1. -5

RD-1058 NA-83 NA-9 1

NA-102 NA-103

and -10 P-5IB-5. -10 and - IS

43-63 13 to -6352: 43-6353 .6752; 43 -675 3 t o -7 112

P-5 18- 10-NA

43·7 113 to -7202; 42 ·/06429 to

41-37352 to 3742 1 4)-12093 t o 12492

P-51B-15-NA

- 106538: 42-10654 1 to - 106738 42-106739 t o - 106908: 42- 106909

42-102979 to 103378. 42- 1033 79 to 103978.

P-5 IC-I -NT

42-102979 to -103328

to -106978: 43-24 752 to -2490 I P-5 IC -5- NT

42- 103329 to - 1033 78:42- 103379 (0

- 103778

P-5I C -10-N T

42-103779 to - 103978: 43-24902 [02525 1;44-10753 to · 10782

42-10654 1 to 106978.

P-5 IC -I I-NT P-5I C- IO-NT

44- 10783 to 44 -108 18 to 44 · 10853 t o 44- 10859 t o

43-6713 to 7202 .42- 106429 to 106538, 43-63 13 to 67 12.

NA-106 NA-107

P-5 ID

43-24752 t o 2490 1 42 -106539 and 106540

P-5ID

42-103379 t o 103978.

NA- I09

P-5 1D-5. -10 44- 13253 to 1575 and - 15

NA- I IO NA-I II

P-5 ID-1 P-5 IC-10.

43-24902 to 2525 1

P-5 ID -5 P-5IK

41-3735 2.4 1-3742 1

43-12093 to -12492 to

43-24902 to 2525 1

NA-I 04

43-6 158 t o-6312

P-5I C- I I- NT P-5IC-10-NT P-5I C- I I-N T P-5 IC-10-NT XP-5 ID-NA

-10817 -10852 - 10858 - 11 036

44· 11 037 t o - 11122 44- 11 123 to - 11152

! (disassembled to Australia)

P-5 1D-5-N A

42-106 539. 42- 106540 44- 13253 to - 140 52

44- 1075 3 to 44-111 53 to 44-1 1353 t o 44-1 285 3 to

P-5 ID - 10-NA P-5 1D- r 5- NA

44-14053 to -14852 44-1485 3 to -15252: 44-15253

P-51D-20-NA

to - 15752 44- 6316 0 t o -64 159: 44 -7202 7 to -72 126; 44-72127 to -72626

11152 11352 12852 13252

NA- 112 NA- 122

P-51D-20 P-5 1D P-5I D

NA-I24

P-5I D

44-84390 to 84989. 45- 11343 to 75025

P-5 IM

cance lled, transferred to NA-I 09

44-63 160 to 64 r59. 44- 72027 to 72 126. 44- 72 127 to 73626 . 44-736 27 to 75026

P-51D-25-NA

44-72627 to -73 626 ; 44-73627 to -74226

P-5 ID-30- NA P-51 D-5-NT P-51D- 20-NT

44-74227 to -75026 44- 11153 to - 11352 44- 12853 to - 13252

P-51D

45-75026 cance lled. transferred to NA 26

P-51D-25- NT

NA- 127

44-84 390 to -84989;45 - 11343 to - 1154 2

NA-138

P-5 ID

cance lled. end of war

TP-5 ID

45 - 11443.45 - 11450: 44-8461 0 to -846 11

P-5 IK- I-NT P-5 IK-5-N T

44-11 353 to - 11552 44-11 553 to - 11952

P-5 IK-10-NT

44 -1 1953 to -1 2752; 44- 12753 to - 12852

P-51L-N T P-5 1M-NT

44-91 104 to -92003 (cancelled)

_ _1 "42 ,

P-S I MUSTANG

45-117 43

ROYAL AIR FO RC E MUSTANG SERIALS

XP-5I B

Span

37 ft

Mkl

AG145 t o AG663 ;AG664;AL958 to AM257;

Lengt h

Mk IA

AP164 to AP263 FD41 8 to FD567

Height Wing area

32it 3in 13 ft 8 in

Mk II

FR890 to FR,939

Mk III

FB I ID to fB399; FR4 11 ; FX 848 t o FX 999;

Empty weight Loade d we ight

BBBO Ib

Max speed Ce iling

42,000 h

Climb Po wer plant

3600 fpm (initia l) Packard V- I650-3! t 380 hp

FZIOO t o FZ197; HB821 t o HB961; HK944 to H K947 ; H K955 t o H K956 ; KH42 1 to K H 640; SR406 to SR440 Mk IV Mk IVA

KH64 1 to KH670

233 sq ft 7050 Ib

441 mph

KH671 to KH870;KM I00 to KM492; T K586;TK589; KM744 to KM799 (cancelled)

P·SIB

Overa ll dime nsions Emp ty we ight

MUSTANG SPECIFICATIONS XP · 5 1

as XP-5 IB 6980 Ib

Loa ded we ight

11,800 Ib

Max speed Cru ise spee d Cei ling

439 mph

C limb Range Pow erp la m

362 mph

4 1,500 ft 30,000 ft in 12. r minut es

Span Length Height Win g are a

37 h 32 ft3 in 12 ft2 in 233 sq ft

Empty weight Lo ade d we ight Max speed

6280 lb

O ve ra ll dimensi on s

as Xp· SIB

8400 lb

Empt y weight Loaded weight

7 100 lb

Crui se speed

300 m ph

437 mph

C eiling

30,800 h 2500 fpm (initia l) 625 to 104 0 miles

Max speed Cru ise speed Ceiling C limb

41,900 h 30.000 it in 13 minutes up to 2800 miles

C limb

Range Pow erplant

382 mph

Ali isonV.1710·39/ 1150 hp

400 to 2700 miles Packard V_ I 650-7/ 1490 hp

P·SID

Range Po we rplant

I 1,600 Ib

362 mph

Packard V· 1650·7 ! 1490 hp

P·51 O verall dimensio ns

as XP-5 1

Emp ty we ight l oaded weight

8800 lb

Max speed C ruise speed

387 mph 307 mph

Ce iling

3 1,300 h

6550 Ib

C limb

2200 fpm (initial)

Range

350 to 1/ 75 miles AllisonV· 1710· 3911 150 hp

Powerp lant P-5 IA Overall dimension s

as XP-51

Empty weight

6430 Ib

Loaded weight

900Q lb

Max speed Cru ise spee d

390 mph 305 mp h

Cei ling

31,400 h

Climb

2300 fpm (initial)

Range

350 t o 2550 miles AllisonV-17 10-81/ 1200 hp

Power plant

APPEND ICIES

143

EIGH TH , NINTH & FIFTEENTH AIR FORCE MUSTANG CODES AJ

AX CG CL CV CS CY FT GQ HL HL HO IV IX JA KI LC LH MC MX MX DC OS PE PI

144

356th FS1354th FG I07th TRSI67, h TRG l8th FSl55th FG ll8th FSl5Sth FG l 68,h FS/l S9th FG l 70th FS/l59th FG l4l,d FSlS5th FG 353,.d FSl354th FG 355th FSl3S4th FG 8l.-d FSI78th FG 30ath FS/31st FG 487th FSl352nd FG l69th FS/l S' th FG

PZ QI QL QP QP SX VF VF VQ

486,h FS/l 52nd FG 36 1St FSt356th FG nnd TRSI69, h TRG ll4,h FSl4th FG

2nd FS/S2nd FG l52nd FSll 5l,d FG ll6th FSll Sl .-d FG 5th FS/52nd FG 8th ATS

VX

I09th TRS/67th TRG

6Sth FW 55th FSl20th FG

WD WD WR WZ WZ YC

77th FsnOth FG

YF

350th FSll 5l ,d FG 7.th FSl20t h FG 82nd FSl78th FG 307th FSJ31 sr FG l5 9th FSll 56'h FG 357th fS/35Sth FG 328th FSIl52nd FG l60th FSIl 56th FG

YJ ZM

ll 5, h FSl4th FG 4th FSl52nd FG l S4th FS/lS5th FG 84th FSI78, h FG l 09th FSil I st FG 10t h TRSl69th TRG l 58th FSllS5th FG l S I st FSll 5l,d FG 12th TRSl67th TRGI 10th PRG l 80th FSll 6l , d FG I60th TRSl36l ' d TRG

162ndTRSlI 0th PRG

P-S I MUSTANG

A' A' Bl Bl B6

38 1st FSJ363rd FG 161st TRS/363rd TRG l6l,d FSll S7th FG

B7 Cl Cl C5 C7 D7 E2 E6 E' G4 )2 L2 N2 N5 R4 SE 5M 5Q 5Y 6N 7F 'B

'D 'H

374th FS/36 I st FG 382nd FS/363rd FG

162nd TRS/363rd TRG l64,h FSll57th FG 555t h FSl496th FlG 50l ,d FSll l 9th FG 375th FS/36 I st FG

402nd FS/l 70t h FG 376th FSf36 I it FG l62nd FSllS 7th FG 435th FS/479th FG 4l4th FSl479th FG l8l,d FSll64th FG II Ith TRSl6.th TRG l6th BS l 8Sth FSll64th FG 15th TRSl67th TRGI 10th PRG S04th FSll l ' , h FG l84th FSll 64th FG 505, h FSll l . th FG 485th FS/37Oth FG 4l 6th FS/47. ,h FG 40 1s! FSJ370th FG 8S7th BS