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 CL.I including three built as floatplanes under the designation CLS.I (factory designation J 11). After the war, one or two CL.Is were converted for commercial service by enclosing the rear cockpit under a canopy. Junkers CL.I The Junkers CL.I was a ground-attack aircraft developed in Germany during World War I. Its construction was undertaken by Junkers under the designation J 8 as proof of Hugo Junkers' belief in the monoplane, after his firm had been required by the "Idflieg" to submit a biplane (the J 4) as its entry in a competition to select a ground-attack aircraft. The J 8 design