Red Bull Stratos Manned Test Jump from 71,581 Feet
The 71,581-foot manned test jump marked the first test of the balloon, capsule and pilot – Felix Baumgartner – in flight.
Preliminary Statistics (currently under review for verification by the Fédéeration Aéronautique Internationale):
Launch time and location: March 15, 2012, 08:10 a.m., at Roswell, New Mexico, USA
– Baumgartner jumped from the capsule at an altitude of: 71,581 feet
– The balloon and capsule took one hour and 34 minutes to complete the ascent
– Baumgartner accelerated to a maximum speed of 364.4 mph
– He spent 3 minutes and 33 seconds) in freefall before pulling his parachute at 7,890 feet
– The pilot landed safely in the desert at 09:50 a.m., about 30 miles from the original launch site
Significance of 71,581 feet
The height was selected for the first manned test because it provides a genuine stratospheric experience beyond the Armstrong Line – the region beginning around 63,000ft where the atmospheric pressure is so low that bodily fluids start to ‘boil’ at the normal temperature of a human body (98.6 °F).
Location
The test was conducted at Roswell, New Mexico, so as to rehearse the launch procedure at the same site selected for the final jump from 120,000ft. The region boasts excellent weather conditions and availability of leading-edge launch resources.
Procedure
The previous evening the Red Bull Stratos team received final safety and weather briefings. Meteorologist Don Day gave the go-ahead that the dawn ‘weather window’ was suitable for an attempted launch: relatively clear skies and calm winds
During the next eight hours, the capsule was positioned in its cradle on the launch crane, the runway cleared of small debris and the balloon laid out on a vast tarp to protect it from tearing
The balloon itself, with a capacity of 1.22 million cubic feet, was significantly smaller than the final mission balloon as it was required to a lower altitude. It weighed 937lbs
Shortly before dawn, balloon inflation began
Baumgartner was suited up and began pre-breathing oxygen to eliminate nitrogen from his blood before he was sealed inside the pressurized capsule
With balloon inflation complete, the capsule lifted off the tarmac to begin its ascent
As expected, the decrease in air pressure as the balloon ascended caused the helium in the balloon to expand to its fully inflated dimensions of 127 feet high and 142 feet in diameter
Once the ascent was completed, Felix ran through his 39-step safety checklist before manually depressurizing the capsule, sliding open the round door and stepping off the external platform
Baumgartner continued in freefall until he reached the optimum height to deploy his parachute and float safely back to earth
Upon landing he was met by the retrieval team, medical checks were conducted, and he was returned to the launch site via helicopter
Once he had been safely retrieved, Mission Control triggered the release of the capsule from the balloon, and both returned slowly to Earth to be collected by the recovery team for evaluation
Hazards
Although 71,581 feet is a stepping-stone to Felix’s final target altitude, the test presented numerous challenges. The normal ceiling for skydiving is less than 15,000 feet.
Potential dangers:
Rapid acceleration and high speed while in freefall – Felix had to ensure he did not go into an uncontrollable spin during freefall
Crash impact in the capsule – the first thousand feet of ascent were critical because if the balloon had failed, neither the capsule nor Felix’s personal parachute would have had time to deploy effectively
Lack of oxygen – during the majority of the trajectory, the surrounding environment contained too little oxygen to sustain human life
Low pressure – without the pressurization provided by the capsule and suit, Felix may have experience life-threatening decompression sickness
Low temperatures – the temperatures Felix experienced in the stratosphere were as cold as anything he’s likely to encounter in his final jump: down to minus 94 degrees Fahrenheit