Junkers Ju 87 near Sagan, 13 Ju 87s and 26 crew members were lost when they crashed into the ground almost simultaneously. The planes dived through cloud, expecting to release their practice bombs and pull out of the dive once below the cloud ceiling, unaware that the ceiling was too low and unexpected ground mist formed, leaving them no time to pull out of the dive. On 1 September 1939, the Wehrmacht invaded Poland, triggering World War II. "Generalquartiermeister der Luftwaffe" records indicate a total force of 366 Ju 87 A and Bs were available for operations on 31 August 1939. The first
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