The Douglas DF was a flying boat designed for commercial use and constructed by the Douglas Aircraft Company.
Its maiden flight took place on 24 September 1936.
The aircraft had a capacity of 32 passengers or 16 individuals in sleeper cabins, and it was the final flying boat produced by the company.
Despite its satisfactory handling and performance within the prescribed specifications, no commercial orders were received.
Consequently, the company was faced with a surplus of aircraft with no domestic market.
To address this issue, the company obtained export permits for the aircraft.
The first two production aircraft were sold to Japan, ostensibly for commercial airline use.
Unfortunately, the second aircraft was lost during a survey flight in 1938.
The second pair of production aircraft, designated as DF-195s, were sold to the Soviet Union.
After being winterized, they were disassembled and transported to Russia via ship.
There, they were operated as transports by Aeroflot. Variants DF-151 Designation of the first two aircraft sold to Japan. DF-195 Designation of the second two aircraft sold to the Soviet Union. Specifications Crew 3 Capacity Up to 32 passengers in four 8-seat compartments Length 69 ft 10.5625 in (21.299488 m) Wingspan 95 ft (29 m) Hull beam 10 ft 3 in (3.12 m) Maximum Hull depth 13 ft (4.0 m) Maximum Height 24 ft 6.25 in (7.4740 m) Wing area 1,295 sq ft (120.3 m2) Mean aerodynamic chord. 14 ft 7 in (4.45 m) Empty weight 16,500 lb (7,484 kg) Gross weight 28,500 lb (12,927 kg) Powerplant 2 × Wright SGR-1820G-2 Cyclone,
9-cylinder air-cooled radial piston engines, 1,000 hp (750 kW) each Propellers 3 bladed constant-speed propellers Performance Maximum speed 167 mph (269 km/h, 145 kn) at sea level 178 mph (155 kn; 286 km/h) at 5,000 ft (1,500 m) Cruise speed 150 mph (240 km/h, 130 kn) at 75% power at sea level 156 mph (136 kn; 251 km/h) at 75% power at 5,000 ft (1,500 m) 164 mph (143 kn; 264 km/h) at 75% power at 9,600 ft (2,900 m) Alighting speed 66 mph (57 kn; 106 km/h) Range 1,500 mi (2,400 km, 1,300 nmi) with 32 passengers 3,300 mi (2,900 nmi; 5,300 km) with 12 passengers Service ceiling 14,300 ft (4,400 m) Absolute ceiling 16,400 ft (5,000 m) Rate of climb 550 ft/min (2.8 m/s) at sea level 585 ft/min (2.97 m/s) at 5,000 ft (1,500 m) Wing loading 22 lb/sq ft (110 kg/m2) Power/mass 0.07 hp/lb (0.12 kW/kg).
Sources
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.
