A-02 flew in November, and then joined the earlier V models at Rechlin-Lärz Airfield for further testing in the contest. A-03 and A-04 were both completed in December, A-03 was a show aircraft and was flown by Heinkel pilots at various air shows and exhibitions, A-04 was kept at Heinkel for various tests. The last two models of the A-0 series, A-05 and A-06, were completed in March 1937. They were both shipped to Japan as the initial machines of the 30 for the Imperial Japanese Navy. In October 1936, the RLM changed the orders for the zero series 112s, instructing Heinkel to complete any A-0s already under construction and then switch the remaining aircraft to an updated design. This gave Heinkel a chance to improve the He 112, which they did by completely redesigning it into an almost entirely new aircraft called the He 112B. It is at this point that it became a modern design that could compete head-to-head with the Bf 109. The He 112B had a redesigned and cut-down rear fuselage, a new fin and rudder and a completely enclosed cockpit with a bubble-style canopy. The canopy was somewhat more complex than later bubble designs; instead of having two pieces with the majority sliding to the rear, the He 112B canopy was in three pieces, the middle sliding back and over a fixed rear section. Even with the additional framing, the He 112 had excellent visibility for its day. Armament was also standardized on the B model with two 7.92 mm (.312 in) MG 17 machine guns in the sides of the cowling with 500 rpg and two 20 mm MG FF cannons in the wings with 60 rpg. For aiming, the cockpit included the new Revi 3B reflector gunsight. The first B series airframe to be completed was V7 in October 1936. V7 used the DB 600Aa engine like the A-series V8, and it also used the original V1 style larger wing. This wing was later replaced with a smaller one but instead of the clipped version from the earlier V models, a new single-spar fully elliptical wing was produced. This design became standard for the entire B series. V7 was turned over to von Braun in April 1937 for yet more rocket tests and managed to survive the experience. It was then returned in the summer and sent to Rechlin where it was used as a test aircraft.