Junkers Ju 87 in place of the carrier-specific Ju 87C series designs, operated from the aircraft carrier "". Other modifications included a flame eliminator and, unlike earlier D variants, two 20 mm MG 151/20 cannon, while the radio operator/rear gunner's ammunition supply was increased by 1,000 to 2,000 rounds. The Ju 87 D-5 was based on the D-3 design and was unique in the Ju 87 series as it had wings 0.6 metres (2-feet) longer than previous variants. The two 7.92 mm MG 17 wing guns were exchanged for more powerful 20 mm MG 151/20s to better suit the aircraft's ground-attack role. The
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