Project Excelsior
Project Excelsior was a series of high-altitude parachute jumps made by Captain (later Colonel) Joseph Kittinger of the United States Air Force in 1959 and 1960 to test the Beaupre multi-stage parachute system. In one of these jumps Kittinger set world records for the highest parachute jump and the longest parachute freefall, both of which still stand (as of 2006).
As jet planes flew higher and faster in the 1950s, the USAF became increasingly concerned with the safety of flight crew who had to eject at high altitude. Tests with dummies had shown that a body in freefall at high altitude would often go into a flat spin at a rate of up to 200 revolutions per minute. This would be potentially fatal.
Project Excelsior was initiated in 1958 to design a parachute system that would allow a safe controlled descent after a high-altitude ejection. Francis Beaupre, a technician at Wright Field, Ohio, devised a multi-stage parachute system to facilitate manned tests. This consisted of a small 6 foot (2 m) stabiliser parachute designed to prevent uncontrolled spinning at high altitudes, and a 28 foot (8.5 m) main parachute that deployed at a lower altitude. The system included timers and altitude sensors that automatically deployed both parachutes at the correct point in the descent.
In order to test the parachute system, staff at Wright Field built a 200 feet (60 m) high helium balloon with a capacity of nearly 3 million cubic feet (85,000 m³) which could lift an open gondola and test pilot into the stratosphere. Kittinger, who was test director for the project, made three ascents and test jumps. As the gondola was unpressurised, Kittinger had to wear a full pressure suit during these tests, plus additional layers of clothing to protect him from the extreme cold at high altitude, and the parachute system itself. This almost doubled his weight.
The first test, Excelsior I, was made on November 16, 1959. Kittinger ascended in the gondola and jumped from an altitude of 76,400 feet (23,300 m). In this first test the stabiliser chute was deployed too soon, catching Kittinger around the neck and causing him to spin at 120 revolutions per minute. This caused Kittinger to lose consciousness, but his life was saved by his main chute which opened automatically at a height of 10,000 feet (3,000 m).
Despite this near-disaster on the first test, Kittinger went ahead with another test only three weeks later. The second test, Excelsior II, was made on December 11, 1959. This time Kittinger jumped from an altitude of 74,700 feet (22,800 m) and descended in freefall for 55,000 feet (16,800 m) before opening his main chute.
The third and final test, Excelsior III, was made on August 16, 1960. During the ascent the pressure seal in Kittinger's right glove failed, and he began to experience severe pain in his right hand. He decided not to inform the ground crew about this, in case they should decide to abort the test. Despite temporarily losing the use of his right hand, he continued with the ascent, climbing to an altitude of 102,800 feet (31,300 m), or almost 20 miles. The ascent took one hour and 31 minutes, and broke the previous manned balloon altitude record of 101,516 feet (30,942 m) set by Major David Simons in 1957. Kittinger stayed at peak altitude for 12 minutes, waiting for the balloon to drift over the landing target area. He then stepped out of the gondola to begin his descent.
The small stabiliser chute deployed successfully and Kittinger fell for 4 minutes and 36 seconds, setting a still-standing world record for the longest parachute freefall (although some authorities do not count this as a freefall record because of the use of the stabiliser chute). At an altitude of 17,500 feet (5.3 km) Kittinger opened his main chute and landed safely in the New Mexico desert. The whole descent took 13 minutes and 45 seconds, and set the current world record for the highest parachute jump.
During the descent, Kittinger experienced temperatures as low as −94 degrees Fahrenheit (−70 degrees Celsius). In the freefall stage he reached a top speed that is variously estimated as 614 mph (988 km/h) or 625 mph (1,005 km/h); in later interviews, Kittinger put his top speed at 714 mph (1,149 km/h). As the speed of sound is lower in the upper atmosphere than at ground level, this means he was travelling at transsonic, and perhaps supersonic, speeds. Despite this, Kittinger said he had no sensation of speed until he approached the cloud deck.
A plaque attached below the open door of the Excelsior III gondola read "This is the highest step in the world".
Kittinger's heroic efforts during project Excelsior proved that it was possible for air crew to descend safely after ejecting at high altitudes. For his work on Excelsior, President Dwight D. Eisenhower awarded Kittinger the C.B Harmon Trophy. He also received an oak leaf cluster to the Distinguished Flying Cross, the J.J. Jeffries Award, the Leo Stevens Parachute Medal, and the Wingfoot Lighter-Than-Air Society Achievement Award.
References
- Craig Ryan, The Pre-Astronauts: Manned Ballooning on the Threshold of Space, Naval Institute Press, 1995 (ISBN 1-55750-732-5).