Last changed: v0.2 - 20-04-2020
High altitude skydiving
Skydiving is making a free fall from an aeroplane and landing safely using a parachute. When one goes higher up in altitude, this becomes the High Altitude, Low Opening (HALO) or High Altitude High Opening (HAHO) parachute jumps. When one goes even higher, it comes close to a space dive. A space dive is a parachute jump from space. Even though no space dives have been done, some jumps were performed out of high altitude balloons.
Records
One of the first names that come to mind is that of USAF Colonel Joseph Kittinger. Kittinger jumped from a high altitude balloon and made a parachute jump from a record altitude of 31.3 km in the Excelsior III mission. He made a total of three jumps. The first ended in a near disaster as he entered a flat spin, causing him to lose consciousness. Fortunately, the automated parachute system prevented him from dying. The second jump was a successful repeat of the first jump. Both were performed from about 22-23 km. The third jump was supported by a small drogue parachute stabilising his descent. During the jump, he fell for 4 minutes and 36 seconds and reached a top speed of 988 km/h. The Excelsior jumps were performed to research high altitude bailouts.
Kittinger's record stood for 52 years until Felix Baumgartner broke it as part of the Red Bull Stratos project. He jumped from an altitude of 38.97 km. Even though Kittinger's record was broken, he was the capsule communication for Baumgartner. Baumgartner set two records, the highest parachute jump and the longest free fall. He reached a top speed of 1357.6 km/h and was the first human to break the sound barrier outside a vehicle. As Baumgardner did not use a drogue parachute for stabilisation, his total fall time was 17 seconds shorter than that of Kittinger.
Baumgardner's record was broken two years later by Alen Eustace who jumped from 41.4 km. He, however, did not break the speed record as he to was stabilised with a drogue parachute.
Kittinger, Baumgardner and Eustace are not the only ones to participate in these high altitude jumps. There have been some Russian attempts as well. In 1962 Yevgeni Andreyev and Pyotr Dolgov jumped from 25.4 and 28.6 km respectively. Andreyev successfully deployed his parachute. He did not set the record for the highest jump as Kittings jump was higher, however as he was not stabilised by a drogue parachute, he did set the record for the longest free fall. Baumgardner only broke this record in 2012. Dolgov, on the other hand, impacted the gondola with his visor, leading to suit decompression. He never made it down to the ground alive.
Red Bull Stratosjump
Space jumps
As of 2019 no actual space dives have been attempted or made. The largest challenge at the moment is the release vehicle. All jumps mentioned above has been done from balloons as aircraft cannot fly at such altitudes. However, even balloons cannot reach space. The current altitude record for an unmanned balloon is 53 km. When jumping from space, one can either jump from an orbital platform or a suborbital platform.
Proposed system for astronaut bailout from space
Jumping from an orbital platform has the major disadvantage that one enters the atmosphere at orbital velocities. These velocities directly result in extreme heat during re-entry. Two projects that used attempted to fly similar missions have been done. These are Paracone and MOOSE. Paracone was an inflatable system that provided mission abort capabilities throughout the ascent trajectory. The astronaut would be strapped into his seat, and the cone would inflate behind him. This would result in a protective shell formed around the astronaut. MOOSE was a similar project using a solid heat shield for protection.
