The Arado Ar.66C entered service with the Luftwaffe in 1933 as a two-seat primary trainer. It was still in service at the outbreak of World War II, and in 1943 the remaining aircraft were pressed into service, alongside the Gotha Go.145 trainer, for night ground-attack (Storkampfstraffeln) harrassment operations on the Eastern Front.
Powered by a 240 hp Angus As 10C inverted-vee engine the usual armament on these combat missions was a 2- or 4-kg anti-personnel fragmentation bomblet.
