[1] After completing secondary school when he was sixteen, he started working as a turner at the Krasny Oktyabr plant.

During one test flight of the SB bomber he encountered a birdstrike, causing him to hit his head and losing consciousness before managing to land the plane safety.

While Kuhn was able to fly as far as Vitebsk in his damaged bomber, he was forced to land in Soviet territory, and all four crew members were captured.

[8][9] From July to September 1941 Gallay totaled ten night sorties on the MiG-3 but gained no further aerial victories.

After making contact with the Rognedinsky partisan brigade in the Brynask oblast he was rescued and taken back to Soviet territory, where he returned to working as a test pilot.

The subsequent year he transferred to the reserve with the rank of colonel[13] and returned to working at the Gromov Flight Research Institute as a senior researcher until 1975, and from 1960 to 1961 he worked on the cosmonaut training program,[14] where he participated in the training of the Vostok cosmonauts.

[15] In 1959 Gallay became deputy chairman of the methodological council of the Ministry of Aviation Industry for test flights and assisted in preparation of test flights for new aircraft, including the Tu-144, Tu-154, Il-62, Il-76, and An-22,[7] authoring many scientific papers and receiving his doctorate of Technical Sciences in 1972.

[17] There is a memorial plaque on the house where he lived in Moscow and a minor planet is named in his honor.