Douglas XTB2D-1 'Destroyer II,' February 1945. Built to carry a heavier bomb and torpedo load than any prior carrier aircraft, the XTB2D-1 was powered by a massive Pratt & Whitney R-4360 engine driving contra-rotating propellers. Only two prototypes were completed; the aircraft's size proved impractical for existing carrier decks, and the program was cancelled at the war's end. Project: 218475