Two hang gliders on a tower-block roof in the Leipziger Straße

A Stasi dossier of May 1985 on thwarted escapes by balloon and home-made aircraft describes two young East Berliners, a 22-year-old construction machine operator and a 20-year-old electronics technician, who spent 1983 studying technical literature in libraries, doing calculations and finishing a design for a hang glider. They stole the materials: fabric from a department store and high-quality aluminium tubes from a metal trader.

Over several weeks they built two gliders in a disused spa house and scouted areas in the south of the GDR for test flights, using stolen maps. In August and September 1984 they made trial flights in front of onlookers, claiming they were testing equipment for the GST, the paramilitary sports organisation. One glider was damaged and quickly replaced.

They then reconnoitred the high-rise blocks on the Leipziger Straße in Berlin-Mitte. On 9 October 1984 they forced the security lock of a metal door leading to the roof garden of one of the blocks and replaced it with a lock of their own, so that nobody would discover them. They carried the dismantled gliders up to the roof and assembled them.

On 24 October 1984 they tried to take off, but because of the wind conditions they abandoned the attempts. Fearing discovery, they left, leaving the gliders on the roof above the lift housing. People's Police officers found the two gliders the next day; a GDR-wide search followed and the Stasi identified the pair on 30 October 1984. The Stasi's photographs include a view from the roof across the border strip, with its inner and outer walls and watchtowers, to the Springer building in West Berlin, marked as the 'possible direction of flight'.