Douglas DC-7

Douglas DC-7
Image caption
Description
Role	Civil air transport
Crew	3 or 4
Passengers	99 to 105
First Flight	1953
Entered Service
Manufacturer	Douglas Aircraft Company Long Beach, California
Dimensions
Length	112 ft 3 in	37 m
Wingspan	127 ft 6 in	42 m
Height	31 ft 10 in	10.5 m
Wing area	1,637 ft²	152 m²
Weights
Empty	72,763 lb	33,050 kg
Loaded	lb	kg
Maximum takeoff	143,000 lb	65,000 kg
Capacity
Powerplant
Engines	Four Wright R-3350 radial piston engines
Power	13,600 hp	10,140 kW
Thrust	lb	kN
Performance
Cruising speed	355 mph	570 km/h
Maximum speed	406 mph	650 km/h
Range (DC-7A)	4,605 miles	7,400 km
Range (DC-7C)	5,635 miles	9,016 km
Ferry range	miles	km
Service ceiling	25,000 ft	7,620 m
Rate of climb	1,043 ft/min	318 m/min
Wing loading	87.4 lb/ft²	427.6 kg/m²
Thrust/Weight
Power/Mass	0.10 hp/lb	160 W/kg
Avionics
Avionics

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, 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.

Related content
Related Development DC-4 - DC-6
Similar Aircraft Lockheed Constellation - Boeing 377
Designation Series DC-4 - DC-5 - DC-6 - DC-7 - DC-8 - DC-9 - DC-10
Related Lists List of airliners - List of civil aircraft