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Show TolfBy 9 Story Is B-- 2 -- Speed Marked Development Of Big Plane ESQ First Flight Was in Production (The following article la of printed from the July Issuewas Air Force Magazine. It written by Col. Donald L. Putt, chief, bombardment branch, engineering division, Materiel Command, who was in charge- of the famous XB-2- 9 project. Permission to reprint must be obtained from the War Department Bureau of Public relations, re- B-2- Officer JLE3L' NT W Ciharge aa T moaeu bariy w--, Shown in Contrast to 9 1 -. - ' MiVfetv After Teh Months (-- 1 ( IshriJ k) - D. C. THE Washington, - EDI- TOR.) The was flown for XB-2- 9 the first time in September, 1942. Ten months later, in July, 1943, the first production model of the completed. B-2- Set misst was 9 dam Moot First of the new series of very is far heavy bombers, the p 9 its more than a grown-uname of Superfortress belies the extent of revolutionary design and structural changes incorporated in our newest and biggest tactical is as bomber. Actually, the 9 as the different from the 7 Thunderbolt is from the original Seversky 5 pursuit. Outstanding features of the 9 are: a new type Boeing wing that is claimed to be the most efficient ever designed, a new flap design and landing that limits take-of- f runs to those of and total wing area 19 by increasing extended; a dual per cent when wheel fully - retractable tricycle landing gear; direct actuating controls without booster systems that 2.200 handle easier than a h. p.. Wright Cyclone engines with dual sets of , B-2- eer,' B-1- 7; No ' V " . ent the : mte B-2- leorti B-1- A dUp bead -- hie P-3- B-2- 3-17- 's; turbo-supercharge- rs; four-blade- bys propel- d lers i 9, 7, . e, B-1- 5, 9, - et nt sou-poun- s. M-1- 7. i Maen ire..-- At0m pr&4 . B-2- extra-heav- B-1- J 9 Superfortress that already hu THE LONG AND SHORT. OF" IT . . . Shown above with two earlier AAF models is the gargantuan showered the Nips with tons of heavy explosives. The massive bomber is equipped with twin bomb bay doors to enable the ship to disgorge its destructive cargo without upsetting its balance. The revolutionary new plane is so aerodynamlcally clean the front wheel landing The comparatively mild name "Superfortress" belies its completely modern design gear when lowered doubles wind resistance. Fortress. It carries the biggest bomb load farther, faster and higher than ever before. famous from the different Flying airplane totally so large (16 feet, 6 inches) y bombers,, the XB-2they must be slowed down by now known as the Superfortress. to reduction 35100th gears keep the tip speed under the speed of Between the time the XB-2- 9 de sound. sign was approved and the day it uu made its first test nignt, Is a the third plane Statistically, imto were incorporated changes a the size of with the gain 240 more were speed over 300 m. p. h.. an alti- prove the plane; tude of over 30,000 feet, very long made oeiore ine iirst production was completed. Hundreds .range and a very heavy bomb load. model Its wing span is 141.3 feet, its more have been made since pro These changes length, 99 feet and its height. 27.9 duction started. included built-i-n life raft ejectors feet. on the top of As it will a new chapter and compartments from blunt a switch ' In the AAFswrite the fuselage, concept of aerial to rounded wing tips, lengthening one another this warfare, chapter historical can be revealed con- - of the tail to provide for better - cerning the original conception nacelle contour, improved soundproofing of the cabin, and even the and design development of this relocation of the crew's lavatory . new substratosphere bomber. side of the fuselage from the right middle 1930s, aircraft During the of weight. manufacturers were being coaxed to the left for reasonsfull-sizall- of . the to Inspection along build bigger bombers with by AAF higher altitude performance. The wood mock-u- p was made1940. Two 7 was the first, in 1035. Next engineers in November, was unmonths later, the XB-2- 9 came the XB-1half the again - size of the jigs; four Fortress, but it was too der construction in the simultanslow: the XB-1twice the size of planes were being built the Fortress, was not sufficiently eouslyone for structures testing, maneuveraDie, was limited in per three for night testing. formance by undersized engines. Cost of the first four planes apNeeded Bigger Bomber proximated $6,500,000, including Still, we needed a newer and models and tests. Wind tunnels at bigger bomber. In early 1939. Wright Field. NACA at Langley AAF tactical staffs under General and Moffett Fields and the UniverH. H. Arnold and Materiel Com-- sity of Washington ran exhaustive mand engineers under Mai. Cen tests on models that cost as much P. Echols, prescribed the as $20,000. These tests led to . Oliver requirements around changes in nacelle design for the - military which our next bomber was to be cooling of the huge 2,200 horseWilt. They were assured bv air. power radiol engine; drag was cut . craft engine makers that horse in half from that of the best depower in excess of 2.000 could be signed nacelles on our other bombexpected by the time the plane ers. Even compressibility problems were tackled. , was 10 oe iiown. Next step this was peacetime-w- as Drag was reduced to a minimum to circularize aircraft nunii flush-rivconand butt-joifacturers for designs built around by struction. The plane was "clean" tne military specification. Then. aerodynamlcally, so "clean" that as sketches and proposals began to the landing gear, when extended, flow into the Materiel Command 50 per cent of the drag. at Wright Field, the Germans comprises Further tunnel tests proved launched their war in Euro no that counter-rotatin-wind g propellers on From reports and observations of each side would further German progress In aerial warfare, the aerodynamics improve of the plane by our tactical staff revised its spe torque. However, with cifications to Include leakproof nullifying eye to maintenance problems, fuel tanks, multiple gun turrets, an it was decided to have all propelheavier caliber guns and cannon lers in the same direction. more and of them more range This turning led to further redecision and altitude. and development of a new All sketches submitted by air- search to solve the torque craft manufacturers were rejected rubber design A rudder balance contemporarily, pending the incor- problem. tour also was perfected which poration of these changes dictated eliminated the need for a booster com Two by military necessity. to help the pilot handle the big and Lockheed) panies (Boeing were awarded contracts for an ex ship in flight perimental plane when the plans Major Changes were reau omitted. Lockheed, Again military requirements led which already had the Constella. to a maior change when the fuse tlon "in the works," intended to lage was lengthened three feet to revamp it into a bomber. The permit the hanging of additional d sudden need for thousands of racks oi bombs. No sooner had the structures however, forced Lockheed to drop Its big bomber nroiwt test model been than it Boeing, with its Stratoliner and was moved to completed a specially-con- wun re. vurcrience ine test taed as the manufacturer siruciea where engineers proceededbuilding to do. xo Duild the first of the stroy the plane piece by piece to F-38- ber fro eras Tl eate Dsn StH to B-1- 7s B-2- 4s 1 WW fall! I'ker be determine its ultimate strength and, until these changes were There are 150 electric motors of 'fell made, flight operations were sus- 49 different types. and load capacity. is u The interior of the u-- z Finally, on September 14, 194Z, pended. It was not until Septemof the Strato the first XB-2- 9 taxied out on the ber, 1943, that the first ship again most as larsre- as that liner. The crew is composed runway for the initial flight. Eddie took to the air to resume tests. bombar 11 men pilot, models Allen, Boeing's chief test pilot, Meanwhile, production was the man at the controls. Tne were being fabricated. We were dier, engineer. : navigator, rw For cohuge sky battleship took off, cir- certain enough of the airplane by operator andis gunners. a small washrooa cled Seattle for about an hour and now to go ahead full speed on mfort, there owlanded with the ease of an air mass production. To carry out the and four bunks, witn oxygen can rest on liner. . tremendous program, new plant3 lets, so crew members The plane'i Allen, who seldom voiced an were constructed and tooled up in the way to a . target. more d opinion about any plane (and he Wichita, Kan.; Renton and Seattle, cabin is than those of airlines. had flown hundreds) simply Wash.; Marietta, Ga.; Cleveland, sit in I The pilot and grunted. "She flies." Ohio, and Omaha, Neb. Four difcompartment s one of George Schairer, Boeing ferent manufacturers tackled the large crack aerodynamldsts put it an- program and 41 per cent of their urhr visibility is excellent: tDC7 first "It's the other way: ship work was subcontracted to other can actually - look down throut which, after the first flight, per business establishments through the nose at- the runway wm mits me to go home and have out the United States. When the shooting a landing. The bodamn little to do." 9 came mbardier sits at their feet andxtt first production model The next day, after a final off the line in July, 1943, tallr with ithr without UlteTassembly check-ou- t, and.1 I made a second flight it already The was a engineer phone. modified After a short from the XB model, mainairplane in our new XB-2nno(Ai an tn the rear of theother differon the Unsome I notes: down the ence hop, jotted navigator being in armament, which pilot, believable for such large plane to had been increased as combat dic- side. . so . . controls be easier tated the need for more firepower. easy on to fly than 7 . . . faster than The bomb bay was design! Minor alterations constantly are connecany previous heavy bomber being incorporated as we gain and built in two sections control forces very light , . . stall more flight experience: from com. ted by a novel catwalk. Crew characteristics remarkable for bat experience, additional modifi- memhers now crawl over it, bUtl cations will be suggested to inbelly cart such J heavy plane. . In rapid succession, for weeks crease the effectiveness of this that used by mechanics bfneaa and months, we ran series of care- Superfortress against enemy oppofor high speed, sition and over enemy targets, later models. Auxiliary aropi fully planned tests bomb bay tanks can be carried fuel conlandings and take-offdevel Outstanding aerodynamic vtanil the nlane's range. sumption, speed calibrations, opment in the 9 is the g It Is well protected Dy weight trials and firing practice. 117 wing. It carries a Boeing Allen and I were at the controls high wing loading from all angles. It has new sigWis that its Un BM and inir wnilnmmt the first time we took the plane promised durinff .'landings nnA cannon installations are poweroff with a full load. It was to take-off- s by. a. huge . Fowler-typ- e have been a normal take-of- f, but driven. Crew members are proHuapiea xo ine- wing. The new teot1 hv hea w armor Plating. we inadvertently failed to lower more w has gradual stalling the development of the the flaps. Nevertheless, the heavi wing characteristics and better stall fi ly loaded plane lifted off the warning 'than other times .used on have witnessed the beginning new era in aerial bombardment of the ground about ur h aus Wat nf wnur AA( distance down the runway, fur bombers. The drag per pound of It ! msv decreased. Domo greatly extra-long ther proving our faith in the "li,i?...oem range heavy, Stability of th nlnna Is Ml AnPTTliPS Ml V plane's flying qualities. lent; any tendency to fall off on k.(i. t -- a If is -Kfai Ferret Out Troubles one wing during a stall carries paru oi I lie wunuj nnu ru Usual "teething" troubles of any a into a bank and then into tined to play out major new plane were ferreted out and through uus oi them knocking y siraigni-awaglide. remedied during the flight and Advantages of the MmrrU ground tests fuel gauges, ignition first On a Boeinff nlana systems, auxiliary ors, bombing equipment, fuel cell easier loading of bombs because leaxage, control cable systems, the bomb bay is closer to the Each change carried the plane ground and increased safety in closer to combat. When all of the aMuiugs, particularly in a cross-win"Some employes still are not. Tires are the same size as major "bugs" had been worked those used vuinpiisninn uie reus time off v on and was booked for its The out, the 9 ot form taking gear retracts electrically. dental,prior big show. optical or medical appoint On February 18, 1943. tragedy Brakes are operated bv hy struck. Eddie Allen, with a fine draulic boost the only hydraulic Campbell, OASC civilian person- I .J .. ..tarrlmr crew, was killed in the crash of uevice on me piane. M .1 --1.1 J saiu the No. 2 airplane, which had been jthat the leaveW , Belly landings have been made uciHevine, explained to with several of the the completed flight by help form must be appr test routine. While in sight of the and in no case did Superfortresses such a landing plication In advance, and shown to the wnr cause out in the Diane's field, fire broke any extensive damage to the keeping unit at the clockbou Both ships engines. Allen attempted to get plane. with prior to leaving for the appoW, the big ship back but. when lust a naraiy a jolt to theirstopped crews. ment or treatment. mile short, the plane fell out of The bomber's structural mom form P Then to control and dived into a Seattle bers are thicker than any used in be takenthebyapplication the employe meat packing house. construction doctor giving the PPoln.tme,nIthi Domber previous Naturally, the crash retarded some oz the mem treatment, who must fill "v the program. Causes were indefi- bers are of ahighly e stressed construe. rfrntnii'i oarttfloate on the D8C to the investigation tlon resembling the trusswork of the form. The form must then nite, according report of the crash board. Steps a oridge or a shin's bulkhead. given to the timekeeping unit' Eleven and a half miloa of wlr. the immediately were taken to reduce on the day all firt hazards la the airplane Ing wind through its framework. turnclockhouse to duty, he explained. 1 co-pii- thof-nnffh-lv sound-proofe- co-pil- ot glass-enclos- ed - B-2- CO- 9. ... B-1- -- small-wheel- ed s, B-2- low-dra- B-2- two-thir- 9, ds w ... motor-gener- at . Leave Applications Needed in Advance d. B-2- B-2- 4s s. i web-tvn- |