On December 6, 1959, US Navy Commander Lawrence E. Flint set a new world record when he zoom-climbed his YF4H-1 Phantom II prototype to an altitude of 98,561 feet or 30,041 meters.

The previous altitude record for turbojet aircraft was held by the Soviet Union (USSR). In July 1959, Major V.S. Ilyushin, flying a Tupolev Tu-431, reached an altitude of 94,658 feet or 28,852 meters.

Project Top Flight

To demonstrate the power and versatility of their new fighter jet, the US Navy undertook a series of record-breaking flights. The program was called Project Top Flight.

Commander Lawrence E. Flint, Jr., USN accelerated his aircraft to Mach 2.5 (1,650 mph; 2,660 km/h) at 47,000 ft (14,330 m) and climbed to 90,000 ft (27,430 m) at a 45° angle. He then shut down the engines and glided to the peak altitude. As the aircraft fell through 70,000 ft (21,300 m), Flint restarted the engines and resumed normal flight – Wikipedia

Commander Flint was 39 years old when he made his record-setting flight from Edwards AFB, CA. He was later awarded the Distinguished Flying Cross for his participation in this achievement.

Awarded for actions during the Cold War

The President of the United States of America takes pleasure in presenting the Distinguished Flying Cross to Commander Lawrence E. Flint, Jr., United States Navy, for extraordinary achievement in aerial flight on 6 December 1959. As pilot of a Navy all-weather fighter aircraft, Commander Flint succeeded in establishing a new world jet aircraft altitude record of 98,560 feet. Exercising brilliant airmanship, initiative, and planning ability, he clearly demonstrated the inherent capabilities and the maximum performance of an extremely important Naval aircraft and was instrumental in focusing world attention on the continuing and significant development of the science of aviation in the United States. – Military Times