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Happened as dated, per en.wikipedia.org: "On 27 August 1939, the He 178 V1, the first prototype, performed its maiden flight, piloted by Erich Warsitz."
A dated aviation-history account of the flight, naming Flugkapitän Erich Warsitz, the two short circuits of the airfield, and the HeS 3B turbojet designed by Hans von Ohain.[1]
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