In response to the requirements of five major US airlines, Douglas designed and built the large 52-passenger DC-4, which made its first flight on 7 June 1938. This type was not put into production; instead 61 smaller unpressurised development were ordered by American, Eastern and United Air Lines. This, too, bore the designation DC-4 and the original aeroplane became the DC-4E.
The DC 4 actually saw its first service as the wartime C 54 Skyrnaster (first flight 14 February 1942) when all 24 DC-4A built were taken by the armed forces (designated R5D Skymaster by the Navy).
The DC-4 had a retractable nosewheel undercarriage and was powered by four 820-1,080kW Pratt & Whitney Twin Wasps. It was a long-range heavy logistic transport with a payload of up to 9,980kg.
A total of 207 C-54A were built, followed by increased-capacity C-54B, similar C-54D with Pratt & Whitney R-2000-11 radials, C-54E with convertible cargo/passenger interiors, and C-54G with new engines. Nine hundred and fifty-two Skymasters were completed for the USAAF and 211 for the US Navy.
The C 54D-15DC (USAAF variant of the DC 4, with the DC suffix indicating Douglas Chicago) with four 1,200 hp Pratt and Whitney R2000 7 radials, was operational for the last year of WW2.
USAAF C¬54s were allocated to the USN in July 1945; 92 so transferred.
The C 54Q had R2000 11 engines.
After the war Douglas built 79 civil DC-4-1009 and many of the military aircraft became available for airline operation – mostly with 44 seats but later with as many as 86. On 7 March 1946 American Airlines was first to introduce DC-4 on US domestic services, between New York and Los Angeles. However in October 1945 American Overseas Airlines had introduced DC-4 on North Atlantic services.
From it were developed the larger DC 6 and DC 7 series the Merlin engined Canadair C 4 and the Aviation Traders Carvair nose loading vehicle transport.
One, the VC-54C-DO Sacred Cow, served as President Roosevelt’s special aircraft and a C-54B-1-DO was used by Prime Minister Winston Churchill.
During the first years of the Berlin Airlift corridors, the pilots had to be wary about mock attacks by Soviet MiG fighters or near misses. The mutual mistrust inevitably caused a number of incidents. In April 1952 an Air France DC-4 was shot-up in one of the Airlift corridors by two Russian MiG-15a. A stewardess and two passengers were seriously injured.
A C-54 made the Berlin Airlift’s last flight on 30 September 1949.
The 1956 R5D2-2 radar and radio research aircraft in the US Navy featured a retractable mast with instruments.
When production ceased in 1947, 1,242 had been built, of which hundreds served to re-equip civil airlines during the first postwar years.
In 1963 the Peruvian Air Force bought three DC-4B’s from US dealer Aircraft Corp of Charlotte, NC. Two for passenger transport and the third for use by Peru’s president.
Variation:
Canadair C-54 / C-4 / C-5
DC 4
Engines: 4 x Pratt & Whitney R 2000 SD13G Twin Wasp, 1,450 hp.
Wing span: 117 ft 6 in (35.80 m).
Length: 93 ft 11 in (28,63 m).
Gross weight: 73,000 lb (33,112 kg).
Typical cruising speed: 204 mph (328 kph) at 10,000 ft (3,050 m).
Accommodation: Crew of 5 plus 44 86 passengers.
Typical range: 2,140 miles (3,444 km) with max payload at 201 mph (323 kph).
DC 4
Engines: 4 x P&W R-2000-25, 1065kW
Max take-off weight: 33140 kg / 73062 lb
Empty weight: 20000 kg / 44093 lb
Wingspan: 35.8 m / 117 ft 5 in
Length: 28.6 m / 93 ft 10 in
Height: 8.4 m / 27 ft 7 in
Wing area: 136.0 sq.m / 1463.89 sq ft
Max. speed: 450 km/h / 280 mph
Cruise speed: 365 km/h / 227 mph
Ceiling: 6900 m / 22650 ft
Range w/max.fuel: 6000 km / 3728 miles
Range w/max.payload: 2200 km / 1367 miles
Crew: 4
Passengers: 40-44
Douglas C 54 B Skymaster
Engine : 4 x Pratt&Whitney R-2000-7, 1332 hp
Length : 93.93 ft / 28.63 m
Height : 27.526 ft / 8.39 m
Wingspan : 117.487 ft / 35.81 m
Wing area : 1462.935 sq.ft / 135.91 sq.m
Max take off weight : 73012.0 lb / 33112.0 kg
Weight empty : 38206.0 lb / 17327.0 kg
Max. speed : 238 kt / 441 km/h
Cruising speed : 208 kt / 385 km/h
Service ceiling : 21998 ft / 6705 m
Cruising altitude : 15207 ft / 4635 m
Wing load : 50.02 lb/sq.ft / 244.0 kg/sq.m
Range : 3389 nm / 6276 km
C-54M Skymaster
Engines: 4x Pratt & Whitney R2000-11, 1,350 h.p.
Wingspan: 117 ft. 6 in.
Length: 93 ft. 10 in.
Loaded weight: 73,000 lb
Max. speed: 274 m.p.h.
Ceiling: 22,500 ft.
Typical range: 1,500 miles at 220 mph at 10,000 ft.
Crew: 6
Capacity: 50 passengers, 30 stretchers or cargo.
C 54D-15DC
Engines: 4 x Pratt and Whitney R2000 7, 1,200 hp.
C 54Q
Engines: 4 x Pratt and Whitney R2000 11.
All Aero 