This flight piloted by the civilian test pilot Robert Denn was conducted in connection with Pratt and Whitney J-57-P-21 engine test program on October 22, 1956. The purpose of this particular flight was to determine the ability to obtain afterburner lights after military rated climb with a test afterburner configuration. Take off was made at 10:19am and was uneventful except for a momentary heat and vent overheat light at approximately 3,000 feet. The light went out after power was reduced to approximately 92% RPM. Power was then advanced to military rated power and a climb to 40,000 feet was accomplished. Two descents and climbs between 8,000 feet and 40,000 feet were then made. Approximately 3 minutes after the third descent was started the forward engine compartment fire warning light became illuminated. The throttle was stopcocked but the fire warning light continued to glow after the engine was shut down. All instruments indicated normal both prior to and after engine shutdown and no other evidence of fire was apparent to the pilot. There was no suitable landing area available within gliding range and the pilot considered it too hazardous to attempt an air start, therefore the pilot decided to bail out in accordance with the instructions contained in T.O. 1F00A-1. Ejection was made at approximately 17,000 feet with the aircraft in a 225 knot glide. The pilot suffered no injury except for minor bruises on the calves of his legs caused by the desert bailout pack during touchdown.