Tag Archives: 41-7723

23 December 1941

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A group of new Douglas C-47 Skytrains. The airplane closest to the camera is C-47-DL 41-18415. (Douglas Aircraft Company)

23 December 1941: Although hundreds of Douglas DC-3 commercial transports had been impressed into military service directly from the production line and designated C-48, C-49 and C-50, the first airplane of the type specifically built as a military transport, C-47 Skytrain 41-7722, made its first flight at Daugherty Field, Long Beach, California, on this date. More than 10,000 C-47s would follow. In service with the United States Navy, the Skytrain was designated R4D-1. In British service, it was called the Dakota Mk.I.

The first DC-3-type airplane to be purchased by the Army Air Corps was this Douglas C-41A, serial number 40-070, (DC-3-253A s/n 2145) delivered 11 September 1939. It was used by General Hap Arnold, Chief of Staff, Air Corps.

The primary differences between the civil and military airframes was the addition of a cargo door on the left side of the fuselage, a strengthened cargo floor, a navigator’s astrodome and provisions for glider towing.

Douglas DC-3 (C-47B) three-view drawing. (NASA)

The Douglas C-47 Skytrain is an all-metal twin-engine, low wing monoplane transport with retractable landing gear. It was operated by a minimum flight crew of two pilots, a navigator and a radio operator. The wing is fully cantilevered and the fuselage is of semi-monocoque construction. Control surfaces are fabric-covered.

Early production C-47 Skytrain transports under construction at the Douglas Aircraft Company plant at Long Beach, California. (Library of Congress)

The C-47 is 64 feet, 5½ inches (19.647 meters) long with a wingspan of 95 feet (28.956 meters) and height of 17 feet (5.182 meters). The wing center section is straight, but outboard of the engine nacelles there is 5º dihedral. The wings’ leading edges are swept aft 15.5°. The trailing edges have no sweep. Empty weight of the C-47A is 17,257 pounds (7,828 kilograms) and the maximum takeoff weight is 29,300 pounds (13,290 kilograms).

A Douglas employee at Long Beach, California works on a C-47’s Pratt & Whitney Twin Wasp R-1830-92 radial engine. Stenciling shows that the propellers were inspected 10 October 1942. (Albert T. Palmer/Office of War Information)

The C-47 is powered by two 1,829.4-cubic-inch-displacement (29.978 liter) air-cooled, supercharged R-1830-92 (Pratt & Whitney Twin Wasp S1C3-G) two-row 14-cylinder radial engines. These had a maximum continuous rating for normal operation was 1,060 horsepower at 2,550 r.pm., up to 7,500 feet (2,286 meters), and 1,200 horsepower at 2,700 r.p.m., at Sea Level, for takeoff. Each engine drives a three-bladed Hamilton Standard Hydromatic constant-speed full-feathering propeller with a diameter of 11 feet, 6 inches (3.505 meters) through a 16:9 gear reduction. The R-1830-92 is 48.19 inches (1.224 meters) long, 61.67 inches (1.566 meters) in diameter, and weighs 1,465 pounds (665 kilograms).

The C-47 has a cruising speed of 185 miles per hour (298 kilometers per hour) at 10,000 feet (3,048 meters) and service ceiling of 24,100 feet (7,346 meters).

U.S. Army paratroopers jump from Douglas C-47-DL Skytrain 41-7805. This airplane was in the first production block of C-47s built at Long Beach, California. (U.S. Air Force)

The C-47 could carry 6,000 pounds (2,722 kilograms) of cargo, or 28 fully-equipped paratroopers. Alternatively, 14 patients on stretchers could be carried, along with three attendants.

U.S. Paratroopers board a Douglas C-47 Skytrain for Operation Husky, 9 July 1943. (U.S. Army)
U.S. Paratroopers board a Douglas C-47 Skytrain for Operation Husky, 9 July 1943. This airplane, Douglas C-47-DL 41-18341, was built at Long Beach, California. (U.S. Army)
Douglas C-47 Skytrains at the Midwest City Douglas Aircraft Plant. Douglas produced 13 C-47s a day at this facility. (U.S. Air Force)

© 2018, Bryan R. Swopes