The Martin Model 162A "Tadpole Clipper"

A unique subscale testbed for the hull planform for the Martin Model 162 Mariner flying boat

Martin had moved from military contracts to civilian flying boats in the 1930s which resulted in the Model 130, the first "China Clipper". Increased passenger demand led to Pan American then replacing the Martin 130 with the Boeing 314. This forced Martin to return to military contracts which resulted in 1936 with their proposed Model 160, a four engined flying boat.

As Martin lacked the funds to build the Model 160 without a Navy contract, they saved on development costs by starting work on 1/4 scale flying demonstrator of the Model 160 which the Navy was going to designate PBM. Soon realizing a four engined patrol bomber was not as efficient as a twin-engined design, the Model 160 was redesigned into the Model 162.

As Martin could not afford to redo the 1/4 scale demonstrator, it was modified into a 3/8 scale demonstrator of the Model 162, designated 162A but nicknamed the "Tadpole Clipper". As war clouds in Europe insured full scale development of the Model 162 PBM Mariner, work on the 162A proceeded to ensure there were hiccups along the way.

The Tadpole Clipper had two seats, though the observer seat was eventually swapped out with an additional fuel tank. As there were no engines that could fit the scaled down nacelles, a Chevrolet V-12 engine was installed in the fuselage and drove the propellers via six drive belts.

The Tadpole Clipper made its first flight on 3 December 1937 was used primarily to study the hydrodynamic properties of the PBM Mariner's hull. At the end of 1938 as the Mariner prototype neared completion, the 162A Tadpole Clipper was retired. In 1953, it was donated to the Smithsonian and in 1987, a team of former Martin employees restored the Tadpole Clipper for display on loan at the Museum of Industry in Baltimore.