Junkers Ju 87 below 3g and had lasted no longer than three seconds. In a crouched position, pilots could withstand 7.5g and were able to remain functional for a short duration. In this position, Junkers concluded that ⅔ of pilots could withstand 8g and perhaps 9g for three to five seconds without vision defects which, under war conditions, was acceptable. During tests with the Ju 87 A-2, new technologies were tried out to reduce the effects of g. The pressurised cabin was of great importance during this research. Testing revealed that at high altitude, even 2g could cause death in an unpressurised cabin
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