Engineering Division, Bureau of Aircraft Production

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   Имелись также грандиозные планы по разработке и постройке в большом количестве американской версии истребителя Bristol F.2B, но собрали и облетали только один биплан XB-1, позже переименованный XB-1A. В дальнейшем технический отдел самостоятельно разработал и построил прототипы нескольких самолетов. Среди них был довольно большой триплан G.А.X. (экспериментальный штурмовик) с размахом крыла 19,96 м, разработанный А. М. Лэддоном. Его оснастили двумя моторами Liberty с приводом на толкающие винты. В носовых частях мотогондол располагались бортстрелки. Дополнительные пулеметы установили внутри фюзеляжа для стрельбы вниз. В конструкцию были включены броневые плиты для защиты экипажа в ходе штурмовок. За прототипом последовали 10 серийных самолетов GA-1, построенных фирмой "Boeing".Также разработали и собрали прототип одномоторного штурмовика GA-2. "Boeing" построила еще один глубоко модифицированный прототип, также с кодом GA-2, но в серию он не пошел.
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Flight, April 1921

THE U.S. "G.A.X." GROUND ATTACK TRIPLANE

   THE accompanying illustrations, which we reproduce from our American contemporary Aviation, show one of the ten ground attack triplanes forming a contract with the Boeing Airplane Co., of Washington, U.S.A., placed by the U.S. Army Air Service.
   This machine was built to the designs of the Engineering Division of the Air Service, and the general characteristics are as follows. It is a twin-engined triplane of more or less conventional design, the main distinctive features consisting of the armoured front half of the fuselage, armoured engine housings, and the sloping N interplane struts. The latter arrangement is employed in order to give the same overhang on all wing extremities, the planes decreasing in span from top to bottom.
   The machine carries one pilot and two gunners, operating in all eight machine-guns and one cannon. These three occupants are practically enclosed in armour, which, together with that protecting the engines, weighs about 2,000 lbs. The pilot, who occupies the front cockpit, operates one 37-mm. cannon, a row of four Lewis machine-guns firing forward and downward, and one machine-gun firing upward and over the wings. [This pilot would do well in a jazz band ! - ED.] The gunners' cockpit at the back has two Lewis guns firing downward to the rear through a tunnel in the fuselage, and one shooting up and over the wings. Bomb gear may also be fitted. Aft of the rear gun cockpit the fuselage is of veneer construction.
   The weights and performance of the U.S. G.A.X. are as follow :-
   Weight empty (inc. water) 7,532 lbs.
   Useful load: Petrol 615 lbs.; Oil 60 lbs.; Crew (3) 540 lbs.; Armament 933 lbs.; Equipment, etc. 140 lbs.
   Total weight fully loaded 9,820 lbs.
   Weight/h.p. 11.2 lbs.
   Weight/sq. ft. 9.6 lbs.
   Landing speed 50 m.p.h. Minimum speed 63-6 m.p.h. (at sea level).

   The top plane has an overall span of 65 ft. 6 ins., that of the lower plane being 58 ft. 6 ins. The chord is 6 ft. 8 ins. for the top, and 5 ft. 8 ins. for the middle and lower planes; the gap is 5 ft. There is no dihedral angle on the top plane, but the middle and lower planes have 1 1/2° and 3° respectively; the angle of incidence of all planes is 1 1/2°. There is no stagger and no sweepback. Ailerons are inserted in the upper and middle planes only; the area of the upper ailerons is 36.8 sq. ft., and of the middle ones 21.8 sq. ft., 10 per cent, of each being balancing area. The total supporting surface of the planes is 1,016 sq. ft. The tail consists of a divided triangular stabilising surface of 53.3 sq. ft., to the trailing edge of which are hinged balanced elevators of 36.4 sq. ft. The balanced rudder (45.8 sq. ft.) is hinged to a vertical fin. Dep. Control is used.
   The landing chassis consists of a laminated spruce V located under each engine nacelle, braced by a steel tube running from the axle to the centre of the bottom of the fuselage; each unit has a pair of wheels, and the weight of the two units complete is 385 lbs.
   Two 12-cylindered Liberty engines, each developing 435 h.p. at 1,800 r.p.m., are installed, with Delco ignition, and Zenith carburettors; they drive direct four-bladed propellers of special design. The radiators, mounted in the nose of each nacelle, are fitted with shutters. There is a short exhaust pipe for each cylinder.