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The Lilienthal Normalsegelapparat was the first airplane in series production. It was designed by Otto Lilienthal and built by his company, the Lilienthal Gesellschaft, between 1891 and 1894. The Normalsegelapparat was a glider, not a powered airplane, but it was the first aircraft to be designed and built specifically for flight. It was also the first aircraft to be produced in large numbers, with over 200 units built.