The development of the series was cut short by Kocjan's murder on 13 August 1944 by the Gestapo as part of the 1944 Warsaw Uprising.

After the fair it was purchased by a private buyer and then confiscated by the US government and pressed into military service as a training glider with the designation XTG-7.

MacCready also used the aircraft to set a world altitude record of 9,000 m (29,528 ft) in 1948, flying in the Sierra mountain wave.

Next it was purchased by Eldon M. Wilson who modified the aircraft with a faired fixed main wheel with a brake and added a free-blown bubble canopy.

In July 2011 the aircraft was owned by Dale Busque of Andover, Connecticut and was still registered with the Federal Aviation Administration in the Experimental - Exhibition/Racing category.