Douglas Y1B-7 No.3, belonging to the 31st BS, 7th BG, at Fort Knox, Kentucky, for an exercise in 1933. The camouflage was made up of large patches of dark green, olive drab and purple: under-surfaces were painted light blue. In the background, an 11th BS Curtiss B-2 Condor can be seen
The Douglas Y1O-35 was virtually a biplane from which the lower wing would have been discarded.
The Douglas XO-35 fitted with three-blade propellers. This view shows the distinctive gull wing arrangement and the numerous struts that isolated the engine nacelles from the fuselage.
Wearing fur gloves, an Air Corps pilot poses in front of a brand-new Y1O-35 at March Field.
A line-up of red-nosed Y1B-7s of the 31st Bombardment Group. The second aircraft, '5', was the 'A' Flight leader's aircraft.
Douglas Y1B-7 No.135, of the 88th OS painted with a light blue fuselage and yellow wings and tail. The nose and fuselage stripes were possibly orange. This stripe indicates this was the 'B' flight leader's aircraft.
Y1B-7 No.2 of the 31st BS. Fuselage nose, fuselage hand and aircraft individual number were painted bright red, with a yellow outline. Wheel covers were left in natural metal.
A formation of three Douglas Y1B-7s during a 1933 anti-aircraft exercise. Note that the camouflage pattern differs from one aircraft to another.
Y1B-7 No.7 belonging to the 12th OS flying over Salt Lake during AACMO operations on air mail route 18 (Salt Lake City to Oakland route).
The main external features distinguishing the Douglas XB-7 were its shorter engine nacelles fitted with two-blade propellers
Douglas Y1O-35 No. 174 belonging to the 88th OS. The aircraft was painted in a blue and yellow scheme.
The fuselage of the Douglas XO-35 was covered with stressed skin made of corrugated metal panels.
The Douglas XB-7, at Wright Field on May 3, 1938.
The Douglas XB-7 at Wright Field, in the autumn of 1932. Several bombs are discernible under the belly.
Y1B-7s at the 1933 exercise, warming up their Conqueror engines. The aircraft had been painted with water-soluble camouflage for the occasion.
Y1B-7 No.8 of 12th OS was wrecked during air mail operations. Its front fuselage was presumably white. This aircraft apparently broke its right landing gear while attempting an emergency landing.