Heinkel He 112 V4

11/30/2010. Remarks by Johan Visschedijk: "The first low-wing cantilever monoplane fighter designed by the brothers Walter and Siegfried Günter, the He 112 was to undergo an extraordinary process of incremental redesign that would result in a totally different warplane, in its definitive production form, from that flown as a prototype in June 1935. The first prototype, the He 112 V1, was powered by a 695 hp Rolls-Royce Kestrel V, had a wing span of 41 ft 4 in (12.60 m) and a wing area of 249.73 sq.ft (23.20 sq.m).

The second and third prototypes, the He 112 V2 and V3, by which it was joined in November 1935 and January 1936 respectively, were powered by the 640 hp Junkers Jumo 210C and were initially otherwise similar until, in the spring of 1936, span and wing area were reduced to 37 ft 8.75 in (11.50 m) and 232.5 sq.ft (21.60 sq.m).

The fourth prototype, the He 112 V4, pictured here, was in fact the first pre-series He 112A fighter with a 680 hp Jumo 210Da engine, a new wing of semi-elliptical planform and new horizontal tail surfaces. This aircraft was sent to Spain in December 1936 for operational evaluation with the Legion Condor.

Two further A-series aircraft were meanwhile completed, these being the He 112 V5, which was essentially similar to the V4, and the V6 with radiator bath and vertical tail changes, and the V8, which, completed after the A-series had been overtaken by the radically revised B-series, served as a Daimler-Benz engine test bed, being fitted with a 1,000 hp DB 600Aa. The V8 was later re-engined with the Jumo 210Da, and, in February 1937, assigned to the rocket propulsion development program.

The V3, V4, V5 and V6 were all fitted with twin 0.311 in (7.9 mm) machine guns. The V5 was subsequently modified to take an engine-mounted 0.787 in (20 mm) cannon with which it was shipped to Spain. Dubbed the Kanonvögel (Cannon-Bird), it saw operational use with the Legion Condor."

The following data relate to the He 112 V4 as representative of the A-series.