Heinkel HD 55

The Heinkel HD 55 was a German‑designed, Soviet‑built reconnaissance floatplane that first flew in 1931. Developed by the Hamburg‑based firm Heinkel Flugzeugwerke under the direction of Ernst Heinkel, the HD 55 was intended to meet a requirement of the Soviet Navy for a ship‑borne patrol aircraft capable of operating from destroyers and cruiser‑tenders. Only a few prototypes were constructed in Germany before production was transferred to the Soviet plant in Taganrog, where the type received the local designation K-1. Powered by a single BMW VI liquid‑cooled V12 engine delivering 750 hp, the aircraft featured a biplane wing layout, twin floats, and an open cockpit for a pilot and observer. Its relatively high wing loading and robust construction allowed stable low‑altitude observation and modest dive‑bombing capability. Although quickly superseded by more modern monoplanes such as the Ilyushin DB‑3, the HD 55 provided valuable experience in cooperative design and licence‑production between Germany and the USSR during the interwar period. The aircraft also demonstrated early concepts of naval air‑borne reconnaissance that would shape later Soviet floatplane developments. Its legacy endures as a testament to early international aviation collaboration.

Heinkel

Classification

Production & History

Design & Classification