The German Focke company made in 1942 a single seat observation gyro kit for used from German U-boote. The purpose was to discover Allied ships and the FA-330 could see them from about 20 miles when towed 120 meters up with a cable from the boat. Some 200 were manufactured but their success was very limited.
This Bachstelle was seen at the war museum at Duxford (U.K).
Photographed 2015 by Cees Hendriks (C) Copyright IPMS Nederland
A few scale models exist: in 1/32 FLY has a kit, in 1/48 again FLY but also Kora. In 1/72 Pavla and Blue Rider had kits.
This walk around was first created May 2018 by M. de Vreeze; note the Copyright!