Junkers Ju 87 rely on their instruments for direction. The Ju 87's standard Revi C12D gunsight was replaced with the new Nachtrevi ("Nightrevi") C12N. On some Ju 87s, the Revi 16D was exchanged for the Nachtrevi 16D. To help the pilot see his instrument panel, a violet light was installed. On 15 November 1942, the Auxiliary "Staffel" were created. By mid-1943, "Luftflotte" 1 was given four "Staffeln" while "Luftflotte" 4 and "Luftwaffe Kommando Ost" (Luftwaffe Command East) were given six and two respectively. In the first half of 1943, 12 "Nachtschlachtgruppen" ("night battle groups") had been formed, flying a multitude of different types
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