Junkers Ju 87 the opening day of the offensive, Hans-Ulrich Rudel flew the only "official" Ju 87 G, although a significant number of Ju 87D variants were fitted with the 37 mm (1.46 in) cannon, and operated as unofficial Ju 87 Gs before the battle. In June 1943, the RLM ordered 20 Ju 87Gs as production variants. The G-1 later influenced the design of the Fairchild Republic A-10 Thunderbolt II, with Hans Rudel's book, "Stuka Pilot" being required reading for all members of the A-X project. The Soviet Air Force practice of harassing German ground forces using antiquated Polikarpov Po-2 and R-5 biplanes
Junkers J 2 1916 Hugo Junkers had come to the realization that the continued use of sheet electrical steel was no longer practical for aircraft construction, writing in his diary that: ""As a result of the first (J 1) and second (J 2) aircraft, one would ascertain that the aerodynamic efficiency was very good. We thought we" [the Junkers designers] "were over the hill. This, unfortunately, was not the case. We had to start again from the very beginning. The reason was that in spite of the favorable horizontal speed, the aircraft could not meet the military climb specifications...we had to develop an