Douglas T2D

The Douglas T2D was a twin‑engine torpedo‑bomber biplane built for the United States Navy in the early 1920s. Development began in 1921 when the Navy issued a specification for a carrier‑capable aircraft that could carry a torpedo or a bomb payload while offering greater range and redundancy than the single‑engine models then in service. Douglas Aircraft Company responded with the Model 31, a wooden‑frame aircraft covered in fabric and duralumin, powered by two 450 hp Liberty V‑12 engines mounted on the lower wing. The T2D featured a conventional biplane layout, open cockpits for a pilot and gunner, and a forward‑firing .30‑caliber machine gun with a rear defensive gun. Its maximum speed was about 115 mph, with a service ceiling of 10 000 ft and a carrying capacity of one Mark 9 torpedo or up to 1 200 lb of bombs.

Only 12 T2Ds entered service, operating from the carriers USS Langley and USS Phelps between 1923 and 1927. Though their operational career was brief, the T2D demonstrated the practicality of twin‑engine carrier aircraft, influencing later designs such as the Douglas TBD Devastator. The aircraft thus occupies an important transitional role in naval aviation, bridging the post‑World‑War I era and the more capable monoplanes of the 1930s.