Out of Service: The History of the Douglas DC-7

The DC-7, a variant of the DC-6 produced by Douglas Aircraft Company between 1953 and 1958, was designed to fly the entire length of the United States in eight hours. Unlike the successful DC-3 and DC-6, the DC-7 was Douglas’ final piston-engine aircraft, and none of them are still in service today.

Douglas was initially reluctant to build the DC-7

Pan American World Airways approached Douglass in the latter stages of World War II and asked for a civilian conversion of the company’s C-74 Globemaster military transport aircraft. But Palm Am eventually backed out of the order for what should have been the DC-7, so the designation was temporarily dropped.

However, the concept for the DC-7 was revived when American Airlines requested a jet that could not travel coast-to-coast. However, American Airlines President C.R. Douglas was at first hesitant to build the plane until Smith told him he wanted 25 of them. Douglas estimates the contract will be worth $40 million, more than paying for the first phase of construction.

The DC-7 was slightly larger than the well-known Douglas DC-6 aircraft and would be powered by four Wright R-3350 duplex-cyclone turbo-compound engines, each with eighteen chambers. 70 years ago today on May 18, 1953, the first prototype aircraft took to the skies, according to Airways Magazine. Then, in November, American Airlines received its first DC-7.

American Airlines was the first to offer non-stop coast-to-coast flights

With its transcontinental capability, the DC-7 changed the face of commercial aviation in the United States. Using the aircraft, American Airlines provided the nation’s first nonstop coast-to-coast flight. Subsequently, rival airline TWA was forced to provide comparable service using its Lockheed L-1049 Super Constellation.

Not allowed to fly for more than eight hours, commercial pilots had to run their engines as hard as possible to complete the journey in the allotted time. But the effort involved the risk of engine overheating and failure, forcing some planes to divert to nearby airstrips.

Douglas produced the DC-7B, which Pan Am operated in the summer of 1955 and offered slightly more power than earlier models.For a flight over the Atlantic. The Pan Am DC-7B could fly from New York to London or Paris one hour and forty-five minutes faster than airlines using Boeing’s 377 Stratocruiser. In Europe at this time the design was very successful commercially.

Indeed, BOAC decided to purchase the DC-7 in 1956 after growing tired of waiting for Bristol Britannia aircraft to take delivery. According to This Day in Aviation, the SAS used it elsewhere on some Arctic flights in North America and Asia. The Nordic carrier debuted the DC-7 on its route from Copenhagen to Tokyo (via Anchorage). These long trips were shortened by 2,000 miles (3,219 km) thanks to the DC-7. So the time also reduced from eighteen hours to thirty two hours.

The type outsold the Lockheed L-1649A Starliner in sales, but when the jet-powered Boeing 707 and Douglas DC-8 entered service in 1958 and 1960, sales of the type finally crashed. These models are still in use today by some operators.

According to Delta Flight Museum: the airline disclosed the following:

In addition to the two main cabins, the extended fuselage of the DC-7 and DC-7B (more than eight feet longer than the DC-6) made room for an eight-passenger sky room with forward chairs and a five-seat sky lounge. With the exception of four DC-7B aircraft delivered in 1957 with an all-coach configuration for 90 people, Delta’s DC-7s and DC-7Bs initially carried 69 passengers in all first-class accommodations. Air conditioning and soundproofing upgrades added to the comfort.

Douglas began converting DC-7s into freighters

Douglas began converting some DC-7s in passenger configuration to freighter DC-7Fs in 1959 as passenger demand for the type began to decline. This allowed the aircraft to fly longer. To accomplish this process, the aircraft had spacious front and rear cargo doors and some cabin windows removed.

Douglas produced a total of four different DC-7 iterations, as well as one unbuilt model:

• 105 DC-7 models were built as initial models.
• DC-7Bs were produced; They were long-range versions with larger fuel tanks.
• 121 copies of the DC-7C “Seven Seas”, an even longer-range derivative, are capable of non-stop transatlantic flights.
• DC-7D: An aircraft type that was supposed to be equipped with Rolls-Royce Tyne turboprops but was never produced
• DC-7F:A freight variant of all three production models.

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