History and notes:
Walter Rethel’s last complete de-sign for Arado prior to his transfer to the Messerschmitt organisation was the Ar 66, a two-seat single-bat biplane trainer of mixed construction. The tailplane was mounted on a raised rear fuselage fairing, ahead of the vertical tail surface, which comprised a wholly movable rudder, there being no fin. The prototype, flown in 1932, was designated Ar 66A and was powered by a 240-hp (179-kW) Argus As 10C inline engine. On Rethel’s departure, Dipl. Ing. Walter Blume assumed responsibility for development of the aircraft, which entered series production as the Ar 66C, initial de-liveries being made to the Luftwaffe training schools after the outbreak of World War 2, and as late as 1943 it was pressed into service, together with the Gotha Go 145 trainer, to equip the night ground-attack Störkungkampfstaffeln (intruder squadrons) on the Eastern Front, armed with 2- and 4-kg (4- and 9-lb) anti-personnel bombs.
Ar 66B: the second prototype, designated Ar 66H, was fitted with two wooden floats, and the rudder was extended beyond the bottom of the sternpost, faired into the rear fuselage by the addition of a ventral fin. Ten production Ar 66B floatplanes were subsequently built.