He showed outstanding abilities in complex tests of various airplanes at critical angles of attack, stall, and spin.
He was the first who tested aircraft behavior at high super-critical angles of attack (around 90°) and performed aerobatics such as the "cobra" maneuver.
As part of his preparations for a space shuttle flight, he also accomplished test-flights with Buran's counterpart OK-GLI aircraft.
With Volks's participation as research cosmonaut on the 7th expedition to Salyut 7, one goal of the mission was to evaluate the effects of long-duration spaceflight on a pilot's skills and ability to fly and land an aeroplane safely (in order to prove Volk's ability to control Space Shuttle Buran atmospheric segment of flight).
The appearance of Volk as a crew member caused some, including the British Interplanetary Society magazine Spaceflight, to ask why a test pilot was occupying a Soyuz seat usually reserved for researchers or foreign cosmonauts.