Again, on 17th May 1978, during a live airto-air sortie, a 23 mm High Explosive shell burst as it left the gun muzzle. Shrapnel damaged the aircraft and caused total failure and a serious throttle restriction. The cone extended fully and the associated engine rumbling and surge gave every indication of engine bearing failure. Without electric instruments and Radio Telephony, Group Captain Keelor had no way of either knowing what had happened or of asking for assistance. Assuming that the engine bearing had failed, he decided to attempt am emergency recovery. With his flying skill and experience, he returned to the airfield, set up a flame out pattern and executed a safe landing. The throttle was stuck at 60% revolutions per minute, and in spite of this he was able to stop the aircraft without damage.

Group Captain Denzil Keelor thus displayed conspicuous courage, exemplary professional skill and devotion to duty of an exceptional order.

Gp. Capt. Keelor who had rich and wide combat experience and the destruction of a Sabre aircraft to his credit, was flying a MiG-21 FL on 27 Mar 78, when due to structural failure the canopy of the aircraft detached and flew off. Gp Capt Keelor felt sudden decompression and loss of control, but managed to fly back to base and execute a safe emergency landing without the canopy. Later on 17 May 78, during firing trials one of the 23 mm Cannon Shells exploded causing extensive damage and total electrical failure to his aircraft. He sucessfully executed another safe landing back at his airbase.