Heinkel He 45, 46, 49, 50, 51, 52 and 66

The Heinkel He 45 was a biplane developed as a bomber in the period before Hitler became Chancellor of Germany, but that entered service as a reconnaissance aircraft in the newly public Luftwaffe.
The Heinkel He 46 was a short-range reconnaissance and army co-operation aircraft that was designed as a biplane but entered service as a parasol wing monoplane
The Heinkel He 49 was the designation given to the first three prototypes of the aircraft that entered service as the Heinkel He 51, the first fighter aircraft to be used by the Luftwaffe after its official formation in April 1935.
The Heinkel He 50 was a biplane dive bomber developed for the Japanese Navy before being taken up by the Luftwaffe
The Heinkel He 51 was the first fighter aircraft to be used by the Luftwaffe after its official formation in April 1935
The Heinkel He 52 was a high-altitude version of the He 51, the first fighter aircraft to serve with the new Luftwaffe after its official formation
The Heinkel He 66 was the designation given to a small number of Heinkel He 50 dive-bombers produced for export to Japan and China