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Show fort, there is a small washroom and four bunks, with oxygen outlets, out-lets, so crew members can rest on the way to a target. The plane's cabin is sound-proofed more thoroughly thor-oughly than those of airlines. ' The pilot and co-pilot sit in a large glass-enclosed compartment where visibility is excellent; they o:m actually look down through the nose at the runway when shooting a landing. The bombardier bombar-dier ' sits at then- feet and can talk with either, without interphone. inter-phone. The engineer and radio operator are to the rear of the co-pilot, the navigator on the other side. The bomb bay was designed and built in two sections connected connect-ed by a novel catwalk. Crew mem- j . bers now crawl over it, but a small-wheeled belly cart such as that used by mechanics beneath automobiles may be installed in later models. Auxiliary droppable bomb bay tanks can be carried to extend the plane's range. It is well protected by guns from all angles. It has new sighting sight-ing equipment, and its gun and cannon installations are power driven. Crew members are protected pro-tected by heavy armor plating. In the devlopment of the B29, we have witnessed the beginning of a new era in aerial bombardment.-It bombardment.-It is the first of our AAF extra-heavy, extra-heavy, extra-long range bombers that can strike out enemies in all parts of the world and it is destined des-tined to play a major role in knocking them out of this war. Here's Story of The Superfort The XB-29 was flown for the first time in September, 1942. Ten months later, in July, 1943, the first production model of the B-29 was completed. First of the new series of very heavy bombers, the B-29 is far more than a grown-up B-17; its name of Superfortress belies the extent of revolutionary design and structural changes incorporated in our newest and biggest tactical bomber. Actually, the B-29 is as different from the B-17 as the Thunderbolt is from the original Seversky P-35 pursuit. Outstanding features of the B-29 are: a new type Boeing wing that is claimed to be the most efficient ever designed, a new flap design that limits take-off and landing runs to those of B-24s and B-J7s by increasing total wing area 19 per cent when extended; a dual wheel fully - retractable tricycle landing gear; direct actuating controls con-trols without booster systems that handle easier than a B-17's; 2,200 h. p. 18-cylinder Wright Cyclone engines with dual sets of turbo-superchargers; turbo-superchargers; four-bladed propellers propel-lers so large (16 feet, 6 inches) they must be slowed down by 35 100th reduction gears to keep the tip speed under the speed of sound. Statistically, the plane Is a third again the size of the B-17 with a speed over 300 m.' p. h., an altitude alti-tude of over 30,000 feet, very long range and a very heavy bomb load. Its wing span is 141.3 feet, is length, 99 feet and its height, 27.9 feet. As it will write a neWi chapter in the AAF's concept of aerial warfare, another chapter this pne historical can be revealed :.corv tated the need for more firepow- j er. Minor alterations constantly are , being incorporated as we gain more flight experience; from combat com-bat experience, additional modifications modifi-cations will be suggested to increase in-crease the effectiveness of this Superfortress against enemy opposition oppo-sition and over enemy targets. Outstanding aerodynamic development devel-opment in the B-29 is the low-drag low-drag Boeing 117 wing. It carries a high wing loading that is compromised com-promised during landings and take-offs by a huge Fowler-type flap adapted to the wing. The new wing has more gradual stalling characteristics and better stall warning than other types used on bombers. The drag per pound of lift has been greatly decreased. Stability of the plane is excellent; excel-lent; any tendency to fall off on one wing during a stall carries 1 through into a bany and then into a straight-away glide. Advantages of the tricycle gear first on a Boeing plane are easier loading of bombs because the bomb bay is closer to the ground and increased safety in landings, particularly in a cross-wind. cross-wind. Tires are the same size as those used on B-24s and B-17s. The gear retracts electrically. Brakes are operated by a hydraul-is hydraul-is boosts the only hydraulic device on the plane. Belly landings have been made by several of the Superfortresses j and in no case did such a landing land-ing cause any extensive damage to the plane. Both ships stopped with hardly a jolt to their crews. The bombers structural members mem-bers are thicker than any used in previous bomber construction. Some of the highly stressed members mem-bers are of a web-type construction construc-tion resembling the trusswork of a bridge or a ship's bulkhead. Eleven and a half miles of wiring wir-ing wind through its framework. There are 150 electric motors of 49 different types. The interior of the B-29 is almost al-most as large as that of the Shratoliner. The crew is composed of 11 men pilot, co-pilot, bombardier, bombar-dier, engineer, navigator, radio , operator and gunnres. For com- business establishments throughout! the United States. When the first production model B-29 came off the assembly line in July, 1943, it already was a modified airplane from the XB model, main difference differ-ence being in armament, which had been increased as combat dic- . cerning the original conception and design development of this new substratosphere 'bomber. During the middle 1930's aircraft manufacturers were being coaxed along to build bigger bombers with higher altitude performance. The B-17 was the first, in 1935. Next came the XB-15, half again the size of the Fortress, but it was too slow; the XB-19, twice the size of the Fortress, was not sufficiently maneuverable, was limited in performance per-formance by undersized engines. Still, we needed a newer and bigger bomber. In early 1939, AAF tactical staffs under General H. H. Arnold and Materiel Command engineers under Maj. Gen. Oliver P. Echols, prescribed the military requirements around which our next bomber was to be built. They were assured by aircraft engine makers that horse-power in excess of 2,000 could be expected by the time the plane was to be flown. Next step this was peacetime was to circularize aircraft manufacturers manu-facturers for designs built around the military specifications. Then, as sketches and proposals began to flow into the Material Command at Wright Field, the Germans launched their war in Europe. From reports and observations of German porgress in aerial warfare, our tactica lstaff revived its specifications speci-fications to include leakproof fuel tanks, multiple gun turrets, heavier caliber guns and cannon and more of them more range and altitude. All sketches submitted by aircraft air-craft manufacturers were rejected temporarily, pending the incorporation incor-poration of these changes dictated by military necessity. Two companies com-panies (Boeign and Lockheed) were awarded contracts for an experimental ex-perimental plane when the plans were- resubmitted. Lockheed, which the works," intended to revamp it into a bomber. The sudden need for thousands of P-38s, however, forced Lockheed to drop its big bomber project. Boeing, with its Stratoliner and experience with the B-17, remained as the manufacturer charged to build the first of the extra-heavy bombers, the XB-29, now known as the Superfortress. Between the time of XB-29 design de-sign was approved and the day it made its first test flight, 900 changes were incorporated to improve im-prove the plane; 240 more were made before the first production model was completed. Hundreds more have been made since production pro-duction started. These changes in- tests on models that cost as much as $20,000. These ,. tests led to changes of nacelle design for the cooling of the huge 2,200 horsepower horse-power radial engine; drag was cut in half from that of the best designed de-signed nacelles on our other bombers. Even compressibility problems prob-lems were tackled. Drag was reduced to a minimum by flush-rivet and butt-point construction. con-struction. The plane was "clean" aerodynamically, so "clean" that the landing, gear, when extended comprises 50 per cent of the drag. Further wind tunnel tests prov-1 ed that counter-rotating propellers propel-lers on each side would improve further the aerodynamics of the plane by nullifying torque. However, How-ever, with an eye to maintenance problems, iit was decided to have all propellers turning in the same direction. This decission led to further fur-ther research and development of a new rudder design to solve the torque problem. A rudder balance contour also was perfected which eliminated the need for a booster to help the pilot handle the big ship in flight. Again military requirements led to a major change when the fuselage fuse-lage was lengthened three feef to permit the hanging of additional racks of 500-pound bombs. No sooner had the structures test model been completed than it was moved to a specially-constructed T-shaped test building where engineers proceeded to destroy the plane piece "by piece to determine its ultimate ' Strength ' and load capacity-.' v". .:"..','.'. - . ' Finally, on September 14, 1942, the first XB-29 taxied out on the runway for the ' initial flight. ".Eddie ".Ed-die Allen, Boeing's chief test pilot was the man at the controls. The huge sky battleship took' off, circled cir-cled Seattle for about an hour and landed with the ease - of an airliner. air-liner. . " . . v Allen, who seldom voiced ' an opinion about any plane (and he had flown hundreds) simply grunted, grunt-ed, "She flies." ' George Schairer, one of Bo'eing's crack aerodynamicists put it another an-other way: "It's the first ship which, after the first flight, permits per-mits me to go home and have damn little to do." The next day, after a final check-out, I made a second flight in our new XB-29. After, a short hop, I jotted down some notes: Unbelievable for such large plane to be so easy on controls . . . easier to fly than B-17 . . . faster than any previous heavy . bomber ; . . control forces very light ... stall characteristics remarkable for heavy plane ... In rapid succession, for weeks and months, we ran series of carefully care-fully planned tests for high speed, landings and take-offs, fuel consumption, con-sumption, speed calibrations, weight trials' and firing practice. Allen and I were at the controls the first time we took the plane off with a full load. It was to have been a normal take-off, but we inadvertently failed to lower j the flaps. Nevertheless, the heavily loaded plane lifted off the ground about two-thirds of the : distance down the runway, further proving our faith in the plane's flying qualities. Usual "teething" troubles of any new plane were ferreted out and, remedied during the flight and ground tests fuel guages, ignition systems, auxiliary motor-generators, bombing equipment, fuel cell leakage, control cable' systems. Each change carried the plane closer to combat. When all of the major ''bugs" had been worked out, the B-29 was booked for its big show. On February 18, 1943, tragedy struck. Eddie Allen, with a fine crew, was killed in the crash of the No. 2 airplane, which had been completed to help with the flight test routine. While in sight of the field, fire broke out in the plane's engines. Allen attempted to get the big ship back but, when just a . mile short, the plane fell out of control and dived Into a Seattl2 meat packing house. " ' Naturally, the crash ' retarded the program. Causes were " indefinite, indefi-nite, according to the investigation report of the crash board. Steps Immediately were taken to reduce all fire hazards in the airplane and, until these . changes were made, flight operations were suspended. sus-pended. It was not until September, Septem-ber, 1943, that the first ship again took to the air to resume tests. Meanwhile, production models were being fabricated. We were certain enough of the airplane, by now to go ahead full speed on mass production. To carry out the tremendous program, new plants were constructed and tooled up in Wichita.. Kan., Renton and Seattle, Wash.; Marietta, Ga.; Cleveland, Ohio, and Omaha, Neb. Four different dif-ferent manufacturers tackled the program and 41 per cent of their work was subcontracted to other elude buildt-in life raft ejectors and compartments on the top of the fuselage, a switch from blund to rounded wing tips, lengthening of the tail to provide for better nacelle contour, improved soundproofing sound-proofing of ' the cabin, and even the relocation of the crew's lavatory lava-tory from the right side of the fuselage to the left for reasons o'f weight. Inspection of the full-size, all-wood all-wood mock-up was made by AAF engineers in November, 1940. Two months later, the XB-29 was under un-der construction in the jigs; four planes were being built simultaneouslyone simultane-ouslyone for structures testing, three for flight testing. Cost of the first four planes approximated ap-proximated $6,500,000 including models and tests. Wind tunnels at Wright Field. NACA at Langley and Moffet Fields and the University Univer-sity of Washington ran exhaustive |