Junkers Ju 87 capacity to (500 litres in main fuel tank of which 480 litres were usable + 600 litres from drop tanks). To prevent overload conditions, bomb carrying ability was often restricted to a single bomb if the aircraft was fully loaded with fuel. The Ju 87 R-1 had a B-1 airframe with the exception of a modification in the fuselage which enabled an additional oil tank. This was installed to feed the engine due to the increase in range with the extra fuel tanks. The Ju 87 R-2 had the same airframe as the B-2, and strengthened to ensure it could
Hugo Junkers in Dessau. The iron wings were patented one year later. Junkers had a wind tunnel built and invented a hydraulic brake. He had far-sighted ideas of metal aeroplanes and flying wings, but the necessities of the war held him back. During World War I, the government forced him to focus on aircraft production. In 1915, he developed the world's first practical all-metal aircraft design, the Junkers J 1 "Blechesel" (Sheetmetal Donkey), which survived on display in Deutsches Museum in Munich until World War II. His firm's first military production design in 1916–17 was the armored-fuselage, two-seat, all-metal sesquiplane known by