Boeing TB

The Boeing TB, company Model 63, was an American torpedo bomber biplane designed by the US Navy and built by Boeing in 1927. It was an improved version of the Martin T3M, built entirely of dural with a fabric covering. Its large, unstaggered equal-span wings could be folded aft to reduce the span to 21 feet 8 inches for storage, its wheeled undercarriage could be interchanged with floats, and a glazed station under the fuselage held the bombardier. The crew was three: pilot, gunner and bombardier. Before the three XTB-1 prototypes were even delivered, the Navy's Bureau of Aeronautics concluded from experience with the NAF XTN-1 that a twin-engine aircraft would suit the role better, which made the TB redundant, and no aircraft beyond the three prototypes were built.