The Arado Ar 64 was the first Arado fighter design to progress past the prototype stage, although it never entered service, being superseded by the Ar 65.
The Ar 64 was based on the Arado SD II and SD III, and was a sesquiplane, with a larger upper and smaller lower wing. All but two Ar 64s were powered by the Gnome-Rhône Jupiter radial engine, built under licence by Siemens. The Ar 64 had a conventional welded steel fuselage and wooden wings, with plywood and fabric covering.
The first prototype, Ar 64a, was powered by a 530hp Jupiter VI engine, driving a four-blade propeller that had been created by bolting two two-blade propellers together, so one pair of blades was slightly in front of the other. In 1931 two went to underwent tests at the German base at Lipetsk in the Soviet Union (D-2470/ werk-nr 65 and D-2338, werk-nr 66), and in July-August it was used in mock air combat against the Heinkel HD 38 and Fokker D XIII. As a result of these tests the Ar 64 was viewed as partially suitable for frontline use, but it would actually be the BMW-powered Ar 65 that entered service. At least twenty Ar 64s were built, with that many serving with the Deutsche Verkehrsfliegerschule pilot training centre at Schleissheim.
Two Ar 64b prototypes were built. These were similar to the Ar 64a, but were powered by the BMW VI 12-cylinder inline engine. These two aircraft were the only Ar 64s to use this engine, which became standard equipment on the Arado Ar 65.
The Ar 64c was similar to the Ar 64a, although with some structural changes. At least three must have been produced (D-2766, D-2767 and D-2768), as they are recorded as having been tested at Rechlin.
They were followed by the Ar 64D, the first production version of the aircraft. At least four were built, with D-2075, D-2277, D-2278 and D-2470 undergoing tests at Rechlin. The Ar 64D had modified landing gear and larger vertical tail surfaces.
The final version was the Ar 64E, four of which were tested at Rechlin (D-2279, D-2280, D-2281 and D-2282). This version had a two-bladed propeller, abandoning the makeshift four-bladed model.
Engine: Siemens Jupiter VI radial
Wing span: 32ft 5 3/4in
Length: 27ft 8in
Empty Weight: 2,667lb
Maximum take-off weight: 3,704lb
Max Speed: 155mph at 16,405ft
Armament: Two 7.92mm machine guns