Douglas A2D Skyshark

The Douglas A2D Skyshark was a turboprop-powered attack aircraft built by the Douglas Aircraft Company for the United States Navy.

Design and development
On 25 June 1945, Bureau of Aeronautics (BuAer) asked Douglas Aircraft for a turbine-powered, propeller-driven aircraft. Three proposals were put forth in the next year and a half: the D-557A, to use two General Electric TG-100s in wing nacelles; the D-557B, the same engine, with contra-props; and the D-557C, to use the Westinghouse 25D. These were cancelled, due to engine development difficulties, but BuAer continued to seek an answer to thirsty jets.

On 11 June 1947, Douglas got the Navy's letter of intent for a carrier-based turboprop. The need to operate from Casablanca-class escort carriers dictated the use of a turboprop instead of jet power. The advantages of turboprop engines over pistons was in power-to-weight ratio and the maximum power that could be generated practically. The advantage over jets was that a turboprop ran at near full RPM all the time, and thrust could be quickly generated by simply changing the propeller pitch.

While resembling the AD Skyraider, the A2D was an entirely different airplane, as it had to be, the Allison XT-40-A2 at 5100 hp having more than double the horsepower of the Skyraider's R3350. Wing root thickness decreased, from 17% to 12%, while both the height of the tail and its area grew. Engine development problems delayed the first flight until 26 May 1950, made at Muroc by George Jansen.

Allison failed to deliver a "production" engine until 1953, and while testing an XA2D with that engine, test pilot C. G. "Doc" Livingston pulled out of a dive and was surprised by a loud noise and pitch up. His windscreen was covered with oil and the chase pilot told Livingston that the propellers were gone. The gearbox had failed. Livingston successfully landed the airplane. By the summer of 1954, the A4D was ready to fly. The escort carriers were being mothballed, and time had run out for the troubled A2D program.

Due largely to the failure of the T40 program to produce a reliable engine, the Skyshark never entered operational service. Twelve Skysharks were built. Most were scrapped or destroyed in accidents, and only one is believed to have survived.

Aircraft on display

 * A2D Skyshark, bureau number 125485, is on display at the airport in Idaho Falls, Idaho. It was restored for static display by Pacific Fighters.