Junkers Ju 87 Josef Stalin decreed that no more ships were to pass within range of German aircraft without his personal permission. Towards the end of the war, as the Allies gained air supremacy, the Stuka was being replaced by ground-attack versions of the Fw 190. By early 1944, the number of Ju 87 units and operational aircraft terminally declined. For the Soviet summer offensive, Operation Bagration, 12 Ju 87 groups and five mixed groups (including Fw 190s) were on the Luftwaffe's order of battle on 26 June 1944. Gefechtsverband Kuhlmey, a mixed aircraft unit, which included large numbers of Stuka dive bombers,
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