It was a low-wing monoplane, with the main characteristic of its design being its elliptical wing (which the Günther brothers had already used for the Bäumer Sausewind sports aircraft before they joined Heinkel) and its small, rounded control surfaces.
The first prototype flew on 1 December 1932,[REF] and proved to have excellent performance, setting eight world records for speed over distance, and reaching a maximum speed of 377 km/h (222 mph) [REF].