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Imagine a paraglider cuts his main chute and reaches terminal velocity. Can he still land safely when he deploys hes rescue chute?

The european standards require that paragliding rescue chutes can handle opening shocks as high as 60 m/s at full load. Google tells me that termial velocity is around 53 m/s for a human skydiver. Is that requirement enough to safely say it can handle terminal velocity? Note that a paraglider can have equipment up to 15kg. Is it possible one could hurt himself when opening paraglider rescue chute because they can open to fast?

European Standard EN12491

EDIT: I've found this post where somebody talks about how he deployed a hangglider reserve while he was falling at terminal velocity. He talks about how he survived and how he has seen another similar case where it went the other way.

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    $\begingroup$ The EDIT link is talking about a hang glider incident, I'd expect their reserves to be a lot more sturdy than a paraglider's $\endgroup$ – Dave Gremlin Oct 29 '19 at 9:46
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    $\begingroup$ Just a note on terminal velocity: the 53m/s quoted is for a (trained) skydiver falling belly to earth, arms and legs spread out, and stable (not tumbling or spinning). The most difficult thing to teach beginning skydivers is how to get stable and stay that way. If you're not stable you terminal velocity will be rather higher. Speed competition have been held which reach, IIRC, 90m/s - but a beginner probably wouldn't be able reach and hold that. so a tumbling freefaller (which is likely without specific training) will have a terminal velocity of over 53m/w but less than 90. $\endgroup$ – simon at rcl Oct 29 '19 at 14:39
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I have been told in person by the owner of High Energy Sports, a well-known manufacturer of hang gliding / paragliding emergency parachutes, that their products are not designed to be safely deployed at the terminal velocity of a falling human being. Regardless of what some particular standard might suggest, I doubt that any hang gliding or paragliding emergency parachute is really designed to have a robust safety factor in the context of deployment in a true terminal-velocity freefall. The greatest concern would seem to be catastrophic failure of the parachute and/or harness, not injury to the user due to opening shock, but the latter would seem likely to be a possibility as well.

Keep in mind that a hang glider or paraglider pilot does not actually cut away from the rest of their equipment (e.g. the main canopy of a paraglider) before deploying their emergency parachute. There is no way to easily do so. And that is why the reserve parachute is not designed for a terminal velocity freefall. (Edit: see other answer for an exception-- apparently some paragliding rigs are designed to allow for a cutaway.)

Nonetheless, in an article in "Hang Gliding" magazine from well over ten years ago, well-known test pilot Mark Stucky described an incident from his younger days when he went skydiving using his hang gliding emergency parachute. I don't recall whether the article specified how long he waited before opening the parachute and whether or not he might have been anywhere near the maximum terminal velocity of a falling human being-- one would tend to assume not. He did survive without injury.

See also answers to related question Whats the difference between a paragliding rescue chute and a parachute?

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  • $\begingroup$ Maybe another answer will include links to information from the industry; I suspect a simple google search would turn up such information. Those links could be added to this answer. $\endgroup$ – quiet flyer Oct 28 '19 at 15:40
  • $\begingroup$ If my main chute fails and I need to use my emergency, I'm not sure I'll care that I'm "over speed", the possibility it may work much outweighs reserving yourself to it not and hitting the ground at full speed. $\endgroup$ – Ron Beyer Oct 28 '19 at 15:45
  • $\begingroup$ I have to disagree with "Keep in mind that a hang glider or paraglider pilot does not actually cut away from the rest of their equipment". There is equipment especially designed for this purpose but it is only done on special occasions. And it is being discussed if it is the best option in case of "cloud suck" (When you get sucked to the stratosphere). I've also found this acro equipment which does not contain paragliding rescue chutes but parachutes. But thanks a lot for your answer. $\endgroup$ – NtFreX Oct 28 '19 at 15:55
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There isn't an easy way to 'cut the main' on most paragliders The risers are attached to the harness by maillons and as long as the wing is doing something, they are under tension and difficult to unclip. Also, the reserve is attached to the harness, not directly to the pilot. The whole lot should come down together. One exception to this is a cut-away system that some acro pilots use, when they pull their reserve the wing detatches and deploys the reserve as it goes.

What usually happens is that the wing stops flying, for whatever reason, and if the pilot decides that he/she can't get it working again they will throw their reserve. They will be falling at this point, but since they started from close to zero sink and there is a lot of drag (not enough for a safe landing) from the wing, at the time the reserve is thrown they will be nowhere near terminal velocity. The main problem then is to prevent the wing interfering with the reserve so it should be pulled in and kept out of the way. This page describes the process and there are some 'interesting' videos of what actually happens.

Paraglider reserves are very different from skydiving reserves. The latter are deployed at terminal velocity (or close to it) and have stronger lines and attachments.

I think I'm right in saying that landing on a reserve is never easy (I've never done it). You have less control over where to land and you will come in faster than otherwise. Reserves tend to be small and light to keep weight down.

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