| Douglas DC-7
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Image
caption
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| Description
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| Role | Civil air transport
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| Crew | 3 or 4
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| Passengers | 99 to 105
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| First Flight | 1953
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| Entered Service |
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| Manufacturer | Douglas Aircraft Company
Long Beach, California
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| Dimensions
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| Length | 112 ft 3 in | 37 m
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| Wingspan | 127 ft 6 in | 42 m
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| Height | 31 ft 10 in | 10.5 m
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| Wing area | 1,637 ft² | 152 m²
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| Weights
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| Empty | 72,763 lb | 33,050 kg
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| Loaded | lb | kg
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| Maximum takeoff | 143,000 lb | 65,000 kg
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| Capacity |
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| Powerplant
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| Engines | Four Wright R-3350 radial piston engines
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| Power | 13,600 hp | 10,140 kW
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| Thrust | lb | kN
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| Performance
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| Cruising speed | 355 mph | 570 km/h
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| Maximum speed | 406 mph | 650 km/h
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| Range (DC-7A) | 4,605 miles | 7,400 km
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| Range (DC-7C) | 5,635 miles | 9,016 km
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| Ferry range | miles | km
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| Service ceiling | 25,000 ft | 7,620 m
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| Rate of climb | 1,043 ft/min | 318 m/min
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| Wing loading | 87.4 lb/ft² | 427.6 kg/m²
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| Thrust/Weight |
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| Power/Mass | 0.10 hp/lb | 160 W/kg
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| Avionics
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| Avionics |
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The Douglas DC-7 is an aircraft built by the Douglas Aircraft Company from 1953 to 1958. It was the last major piston transport made by Douglas, coming just a few years before the advent of jet aircraft such as the Boeing 707 and Douglas DC-8. 338 were produced: about 40 are still in service.
History
Pan American World Airways originally requested the "DC-7" in 1945, as a civilian version of the C-74 Globemaster military transport. It cancelled its order shortly afterward.
American Airlines revived the designation when it requested an extended-range DC-6 for its transcontinental services. At the time, the Lockheed Constellation was the only aircraft capable of making a nonstop coast-to-coast flight in both directions. Douglas was reluctant to build the aircraft until AA president C. R. Smith placed a firm order for twenty-five at a price of $40 million, covering Douglas's development costs.
The prototype flew in May of 1953, and American received its first DC-7 in November, inaugurating the first nonstop coast-to-coast service in the country (taking 8 hours) and forcing rival TWA to offer a similar service with its Super Constellations. The DC-7, however, suffered from unreliable engines, and many transcontinental flights had to be diverted because of in-flight engine failures.
The early DC-7's were only sold to U.S. carriers. European carriers could not take advantage of the small range increase in the early DC-7, so Douglas released an extended-range variant, the DC-7C (Seven Seas) in 1956. Pan Am used DC-7C aircraft to inaugurate the first nonstop New York-London service, forcing BOAC to buy the aircraft rather than wait on the delivery of the Bristol Britannia. The DC-7C found its way into several other overseas airlines' fleets, including SAS, which used them for cross-polar service to North America and Asia. However, the 7C's sales were cut short by the arrival of the 707 and DC-8 a few years later.
Starting in 1959, Douglas began converting DC-7A and DC-7C aircraft into DC-7F freighters, which extended the life of the aircraft past its viability as a passenger transport.
Airlines
Historical operators of the DC-7 include Alitalia, American Airlines, BOAC, Braniff Airways, Caledonian Airways, Delta Air Lines, Eastern Airlines, Emirates, Japan Airlines, National Airlines, Northwest Orient, Panair , Pan American World Airways, Sabena, SAS, THY, and United Airlines.
Today, many DC-7's are based in the western United States, and used for pouring water on wildfires ("water bombing"). A few others are used for air cargo. Due to its engine problems, the DC-7 has not had the same longevity as the DC-6, which is still used by a number of commercial operators. The U.S. military also passed on the DC-7, although a few foreign militaries purchased the aircraft as a transport.
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