Junkers setbacks with crashes of prototypes in 1937 and 1938. Further refinements enabled certification in 1939 and spurred South African Airways to make an initial order for two aircraft fitted with US-built Pratt & Whitney engines. Just as the aircraft was being readied for its first commercial flights, World War II began. With the outbreak of hostilities, all models were requisitioned by the Luftwaffe for military air-transport roles, and later, long-range maritime patrol. Military aircraft production was begun by the company in the 1930s and eventually monopolized all its resources. Perhaps the most notable design was the Junkers Ju 87 "Stuka"
Junkers Jumo 012 December 1944, the RLM issued an order to Junkers calling for the firm to cease development on the 109-012, and further design work was moved to several other firms. By the end of the war, only one mock-up had been completed. Junkers Jumo 012 The Junkers Jumo 109-012, known colloquially post-war as Jumo 012, was a turbojet engine under development in Germany during the Second World War. In essence, it was a scaled up version of the Jumo 004 which had already reached serial production by the end of the war. It was intended to power the EF 132 and