HD 28

Heinkel HD 28 was a prototype reconnaissance seaplane of German production from the interwar period in a biplane, mixed structure, fixed undercarriage - float. The drive was provided by a single Lorraine Dietrich engine with 710 HP. The first flight of this machine took place in 1926 - but the plane never entered mass production. Only one copy of it was made. The machine did not have on-board weapons. Heinkel HD 28 was developed at the Heinkel Flugzeugwerke works by the command of the Imperial Japanese Navy. The main criterion set by the client for the new plane was the longest possible flight time, up to 8-9 hours. After the flight, the machine was handed over to trials in Japan in 1927, where it fared very badly - the plane did not have the expected performance, and the engine turned out to be completely underdeveloped and highly malfunctioning. For these reasons, Heinkel HD 28 was rejected by the command of the Japanese Navy. His later modernization attempts in Japan also failed. Poland also rejected the HD 28 as an aircraft for its Marine Aviation Squadron.