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To survive this is absolutely incredible, the only pitty is that the article lacks so many interesting details! Was he wearing the chute on his back? (So,he ha

To survive this is absolutely incredible, the only pitty is that the article lacks so many interesting details! Was he wearing the chute on his back? (So,he had to get out of his seat to be able to open) What kind of AAD was he wearing ? (was it an off the shelf AAD like a Cypress?) What where it's settings? pass through such altitude at such vertical speed to open.. Any one knows? any links?

smackfu 12y ago
Good thing: NTSB will release a full report at some point with all these answers. Bad thing: Until then, they tend to not say much.
- JshWright 12y ago
  Some might consider that to be two good things...
smu3l 12y ago
I couldn't find any information on who manufactured the automatic activation device, but it was almost certainly not an off the shelf model. Airtec created a specialized Cypres[1] for the Redbull Stratos project, and Cypres has had other applications in space, so I wouldn't be surprised if that's what was used. [1] http://www.cypres.cc/index.php?option=com_content&view=article&id=298&Itemid=166&lang=en http://www.cypres.cc/index.php?option=com_content&view=artic...
sebcat 12y ago
AADs have barometric sensors. That works for skydivers because they zero it on the ground, they're in an unpressurized vessel and they always experience the same force vectors (with variations, belly vs. freefly &c). How would you build a CYPRES-style (barometric, integrated, cutter based) AAD for an event like this? And why would you not have it built into the seat? Speculation: they wore standard bail outs sans AAD, like regular pilots. This guy either don't remember pulling or had the forces excerted on him and/or his gear pull for him.
- InclinedPlane 12y ago
  CYPRES AADs work based on calculating rate of decent, not from some triggered barometric pressure. With modern micro-controllers it's practically trivial to tell the difference between a barometric altimeter sensor history of pressure changes in a cabin and pressure changes due to free falling through the open atmosphere. From there it's just a matter of triggering based on rate of decent, altitude ranges, etc. Some "selling points" of the CYPRES-2: http://www.cypres-2.com/ http://www.cypres-2.com/ Note how they call out that you can keep it activated on the ground, in vehicles, in pressurized cabins, etc. without fear of accidental automatic activation.
  - sebcat 12y ago
    Rate of descent is calculated from barometric pressure in a CYPRES. When a CYPRES is turned on, it calibrates itself and uses the current barometric pressure to determine the reference ground. When you enter an unpressurized aircraft and begi your ascent, the CYPRES will arm itself above a certain altitude (1000 ft normally). When you exit the aircraft, the CYPRES knows your altitude because of the difference in barometric pressure between the reference ground and the urrent pressure. It will also calculate your rate of descent from change in barometric pressure over time. It will activate if you're too low and too fast. Notice how the environment is fairly static. You're jumping right above your reference. You're in an unpressurized vessel so the CYPRES can tell when to arm itself. You're starting a descent by exiting a level-flying aircraft. Any departure from normal operating limits and the CYPRES will not arm itself or activate at the proper speed and altitude. You want a system like fighter pilots have and not something skydivers use. The environments are different, the operational requirements are different.

smackfu 12y ago

Good thing: NTSB will release a full report at some point with all these answers. Bad thing: Until then, they tend to not say much.

JshWright 12y ago
Some might consider that to be two good things...

smu3l 12y ago

I couldn't find any information on who manufactured the automatic activation device, but it was almost certainly not an off the shelf model. Airtec created a specialized Cypres[1] for the Redbull Stratos project, and Cypres has had other applications in space, so I wouldn't be surprised if that's what was used. [1] http://www.cypres.cc/index.php?option=com_content&view=article&id=298&Itemid=166&lang=en http://www.cypres.cc/index.php?option=com_content&view=artic...

sebcat 12y ago

AADs have barometric sensors. That works for skydivers because they zero it on the ground, they're in an unpressurized vessel and they always experience the same force vectors (with variations, belly vs. freefly &c). How would you build a CYPRES-style (barometric, integrated, cutter based) AAD for an event like this? And why would you not have it built into the seat? Speculation: they wore standard bail outs sans AAD, like regular pilots. This guy either don't remember pulling or had the forces excerted on him and/or his gear pull for him.

InclinedPlane 12y ago
CYPRES AADs work based on calculating rate of decent, not from some triggered barometric pressure. With modern micro-controllers it's practically trivial to tell the difference between a barometric altimeter sensor history of pressure changes in a cabin and pressure changes due to free falling through the open atmosphere. From there it's just a matter of triggering based on rate of decent, altitude ranges, etc. Some "selling points" of the CYPRES-2: http://www.cypres-2.com/ http://www.cypres-2.com/ Note how they call out that you can keep it activated on the ground, in vehicles, in pressurized cabins, etc. without fear of accidental automatic activation.
- sebcat 12y ago
  Rate of descent is calculated from barometric pressure in a CYPRES. When a CYPRES is turned on, it calibrates itself and uses the current barometric pressure to determine the reference ground. When you enter an unpressurized aircraft and begi your ascent, the CYPRES will arm itself above a certain altitude (1000 ft normally). When you exit the aircraft, the CYPRES knows your altitude because of the difference in barometric pressure between the reference ground and the urrent pressure. It will also calculate your rate of descent from change in barometric pressure over time. It will activate if you're too low and too fast. Notice how the environment is fairly static. You're jumping right above your reference. You're in an unpressurized vessel so the CYPRES can tell when to arm itself. You're starting a descent by exiting a level-flying aircraft. Any departure from normal operating limits and the CYPRES will not arm itself or activate at the proper speed and altitude. You want a system like fighter pilots have and not something skydivers use. The environments are different, the operational requirements are different.