The Douglas O-43 was a monoplane observation aircraft that was utilized by the United States Army Air Corps.
In 1931, an order was placed for five Y1O-31A service-test aircraft, which were delivered to the USAAC in early 1933 and designated as Y1O-43.
These aircraft differed from the final configuration of the O-31A, featuring a wire-braced parasol wing and a new fin and rudder.
In 1934, an order for 23 O-43A aircraft was completed, which featured a deepened fuselage that eliminated the need for the ventral bulge under the observer’s position.
The aircraft was powered by a single 675 hp Curtiss V-1570-59 inline engine and had taller vertical surfaces with an inset rudder similar to the O-31A.
The canopy was enlarged and fully enclosed both cockpits.
The O-43 and O-43A served with the USSAC observation squadrons for several years before being assigned to National Guard units, such as the 111th Observation Squadron at Brownwood Airfield in Texas, the 15th Observation Squadron at Fort Sill in Oklahoma, and the 3rd Observation Squadron at Langley Field in Virginia.
The 24th airframe of the O-43A contract was completed as the XO-46 prototype. Specifications O-43A Crew 2 Length 33 ft 11 in (10.34 m) Wingspan 45 ft 11 in (14.00 m) Height 12 ft 3 in (3.73 m) Wing area 334 sq ft (31.0 m2) Empty weight 4,135 lb (1,876 kg) Gross weight 5,300 lb (2,404 kg) Powerplant 1 × Curtiss V-1570-59 Conqueror V-12 liquid-cooled piston engine, 675 hp (503 kW) Propellers 3-bladed metal propeller Performance Maximum speed 190 mph (310 km/h, 170 kn) Cruise speed 163 mph (262 km/h, 142 kn) Service ceiling 22,400 ft (6,800 m) Time to altitude 5,000 ft (1,500 m) in 3 minutes 18 seconds Wing loading 15.8 lb/sq ft (77 kg/m2) Power/mass 0.127 hp/lb (0.209 kW/kg) Armament Guns 1 x fixed & 1 x flexible .30 cal (7.62 mm) Browning machine gun. Sources McDonnell Douglas Aircraft Company 1st 75 Years Aviation Book-McDonnell Douglas. McDonnell Douglas Aircraft since 1920, Volume 1-René J Francillon. San Diego Air and Space Museum Archive. The National Museum of the U.S. Air Force.
