83 years ago on this day, the Douglas DC-4E (NX18100, s/n 1601) made it its first flight on this day in 1938 out of Clover Field, Ca, USA.
The DC-4E was designed for United Airlines, the idea was to get a larger and more advanced replacement for the DC-3 (The DC-3 made its first flight in December 1935 and entered service with American Airlines in June 1936)
The DC-4E never made it to the production phase, after proving flights by United Airways, it was (for the time) too complex, too large and therefore too expensive to operate.
The partners in the DC-4E project (American Airlines, Eastern,
Pan American, Trans World and United) provided Douglas with an extensive list of required changes to the DC-4E. This led to the design of the very successful DC-4A, the DC-4 as we know it.
DC-4E, note the toe-out on the engines, especially the outer engines
The DC-4E was designed to carry 42 passengers for day flights and 30 for sleeper (night flights) and was the first large commercial aircraft to have a nosewheel. Other features were, APU's, boosted flight controls, AC electrical system and airconditioning. For production models also Cabin Pressurisation planned. With the triplefin, the aircraft's tail height was low enough to fit in the hangers of the time. The four powerplants were P&W R-2180-A radial engines, getting 1450 HP out of its 14 cylinders. They were mounted slightly toe-out to improve engine out handling, the outer engines more than the inner engines. (clearly visible on the drawing above)
Some more specifications of the DC-4E: Crew: three
Capacity: 42 passengers
Length: 97 ft 7 in (29.74 m)
Wingspan: 138 ft 3 in (42.14 m)
Height: 24 ft 6 in (7.48 m)
Wing area: 2,155.01 sq ft (200.207 m2)
Empty weight: 42,564 lb (19,307 kg)
Gross weight: 61,500 lb (27,896 kg)
Max takeoff weight: 66,500 lb (30,164 kg)
Powerplant: 4 × Pratt & Whitney R-2180-S1A1-G Twin Hornet 14-cyl. two-row air-cooled radial piston engines, 1,450 hp (1,080 kW) each
Propellers: 3-bladed metal variable-pitch propellers
Maximum speed: 245 mph (394 km/h, 213 kn) at 7,000 ft (2,134 m)
Cruise speed: 200 mph (322 km/h, 174 kn)
Range: 2,200 mi (3,500 km, 1,900 nmi)
Service ceiling: 22,900 ft (7,000 m)
Rate of climb: 1,175 ft/min (5.97 m/s)
Wing loading: 28.5 lb/sq ft (139 kg/m2)
Power/mass: 0.0943 hp/lb (4.8kW/kg)