Designed over a two year period by chief engineer Arthur Emmons Raymond and built for American Airlines, the DST, or Douglas Sleeper Transport, was the original variant of the DC-3 commercial airliner. It had 14 sleeping berths for passengers on overnight transcontinental journeys, and could fly across the United States with three refueling stops. There were no prototypes built. X14988 was a production airplane and went to American Airlines where it flew more than 17,000 hours. Following the Civil Aeronautics Board approval of the airplane’s type certificate, the registration was changed to NC14988.
NC14988 was delivered to American Airlines11 July 1936, assigned the line number A115, and named Texas. It was sold to TWA on 14 March 1942.
Just two weeks later, the airliner was impressed into military service and designated C-49E Skytrooper. The U.S. Army Air Forces assigned the serial number 42-43619.
On 15 October 1942, it crashed 2 miles (3.2 kilometers) from its destination at Chicago, Illinois, killing the 2-man crew and all 7 passengers. The airplane was damaged beyond repair.
The DST and the DC-3 were an improved version of the Douglas DC-2 commercial transport. It was an all-metal, twin-engine, low-wing monoplane with retractable landing gear. The airplane was operated by a pilot and co-pilot.
The Douglas DC-3 was 64 feet, 5½ inches (19.647 meters) long with a wingspan of 95 feet, 0 inches (28.956 meters). It was 17 feet, 0 inches (5.182 meters) high in three-point position. 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. The airplane weighed 16,384 pounds (7,432 kilograms) empty and had a gross weight of 24,400 pounds (11,068 kilograms).
The engines were soon changed to more powerful 1,829.389-cubic-inch-displacement (29.978 liter) air-cooled, supercharged Pratt & Whitney Twin Wasp SC3-G 14-cylinder radials, with a normal power rating of 950 horsepower at 2,550 r.p.m., and takeoff power rating of 1,050 horsepower at 2,700 r.p.m. The SC3-G had a 16:9 propeller gear reduction ratio. It was 5 feet, 1.50 inches (1.562 meters) long, 4 feet, 0.19 inches (1.224 meters) in diameter, and weighed 1,457 pounds (661 kilograms).
The DC-3’s cruise speed was 180 knots (207 miles per hour/333 kilometers per hour), and its aximum speed was 200 knots (230 miles per hour’370 kilometers per hour) at 8,500 feet (2,591 meters). The service ceiling was 23,200 feet (7,071 meters).
The DC-3 was in production for 11 years. Douglas Aircraft Company built 10,655 DC-3s and military C-47s. There were another 5,000 license-built copies. Over 400 DC-3s are still in commercial service. The oldest surviving example is the sixth DST built, originally registered NC16005.
¹ In 1935, experimental aircraft, indicated with the letter “X” preceeding their registration number, were prohibited from displaying the United States national designation, the letter “N.”
© 2018, Bryan R. Swopes
