Focke-Achgelis Fa 330 – Bachstelze – German Reconnaissance Autogyro. This unpowered Rotor Kite was pulled by a moving U-boat, the draft made the rotors turn and created a lifting power. It got to max 120 meters high giving the spotter an 45 kilometer 360 vision around the U-boat. Due to the low profile of the U-boat the vision from the conning tower was not much more than 9 kilometer. Unused the Focke-Achgelis was stored in watertight containers and set up by a crew of two in 4 minutes, in calm weather. In rough weather it took about 20 minutes to set the Bachstelze (Wagtail) up.
Photographed in Berlin at the Deutsches Technik Museum in 2016.