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This weekend I had my first gliding experience in an ASK21. My first surprise was being given a parachute. The briefing was simple, if we have a mid air collision, unbuckle the belt harness, remove the canopy with the emergency release, jump out, then pull the chute.

Now, I've spent a fair bit of time flying around at a couple of thousand feet and know how little time it takes to get from there to the ground. I cannot imagine how all of the above could be achieved from the typical gliding altitude of 2,000 - 3,000ft. Especially as getting out could involve re-orienting yourself from an inverted or otherwise non-stable position.

So, what realistically would be the minimum altitude required to do all of this and survive? What statistics are there, if any on glider pilots bailing and what is the survivability from different altitudes?

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    $\begingroup$ Rob Davies bailed out of Big Beautiful Doll (a P-51) at Duxford in 2011 - "According to Davies, he was at about 500 feet, "at the time of decision-making." "And by the time I got out and got the 'chute open I was down to 200 feet. " There's a video of it on YouTube $\endgroup$ May 13 at 12:54
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    $\begingroup$ "the typical gliding altitude of 2,000 - 3,000ft" -- as the posted answer has indicated, that altitude range is plenty for bailing out successfully. But, many readers will be noting, in many parts of the world the "typical" altitude for a glider on a good soaring day is much higher than that! $\endgroup$ May 13 at 14:35
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    $\begingroup$ PS I personally know a glider pilot who has used his parachute, within the last ten years, talked to him just this weekend, the (open-class) glider broke up during attempted spin recovery after accidentally entering a spin during strong thermal turbulence. That's not typical, but it has happened. Sorry though I don't recall the altitude where he left the glider. Considering the part of the country and the time of year, it's very likely that portions of the flight were well over 10,000' AGL. $\endgroup$ May 13 at 14:49
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    $\begingroup$ @quietflyer I should have said the typical tug altitude I guess $\endgroup$
    – Cloud
    May 14 at 8:45
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    $\begingroup$ @Cloud the most likely place for a midair is approaching or in the circuit, with aircraft on converging paths. That goes for airplanes and gliders. Joining the downwind, or on the base leg. For gliders, the next most likely place is in a gaggle in a thermal, which is the main reason single seaters a designed to be flown with parachutes. When I'm out soaring I might join a two seat training glider (often they won't have parachutes) in a thermal but I'll leave if I find myself getting close to them, cognizant of the fact they are parachuteless. $\endgroup$
    – John K
    May 15 at 0:38

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I fly gliders regularly and wear a parachute most of the time, and am also an ex skydiver. Strong parachutes indicates the opening distance of an emergency parachute is 150-300 ft, and advises bailing out at no less than 500 ft to be sure of full inflation before reaching the ground (though you could probably get away with 400 ft or less if you didn't dawdle).

In any case, in a mid air in the circuit at 800 to 1000 ft, with a glider whose control is doubtful, it's bailout time for sure.

The psychological barrier to bailing out can be pretty strong, especially close to the ground, and especially if there is the prospect of maintaining control of the aircraft. At 500ft it's going to look like you are jumping off the roof of a building even though it's plenty of height margin (base jumpers jump from that height all the time).

I once witnessed a midair between two gliders at about 1300 ft near the field. One glider more or less blew up while its pilot was in minding his own business in a thermalling turn (two gliders in adjacent thermals lost track of each other) as its tail boom was chopped off by the wing of the other glider and it simply disintegrated into pieces. He found himself falling strapped to a part of the fuselage shell and one wing. Released the seat harness, dropped clear of the piece, pulled the ripcord, and floated to a safe landing (the wing and fuselage chunk autorotated to the ground nearby, like the World's Largest Maple Seed). Easy, because that was the only option available.

The other pilot had a section of leading edge crushed into the spar and was having control problems where he would stall and roll off, but would recover, repeat, recover, repeat. He went in descending circles rolling off and diving then levelling off again. He stayed with it until it was too late and eventually dived straight into the ground. It's likely that the fixation on maintaining control, combined with the scariness of an exit below 1000ft did him in, though he had ample opportunity to bail out.

In any case, at normal circuit altitude and above, not a problem. And really, if your glider's missing a wing, you're going to try it no matter how low you are.

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    $\begingroup$ This psychology of hoping to maintain control is why at my gliding school we were instructed that if we lose elevator control, it is technically possible to land safely by using the trimmer (our instructor did this once, in an emergency, but he has a lot of experience), but we are advised to bail out nevertheless, as it is extremely difficult to do so, and even more difficult for novices to realize how difficult it is, in the situation. (Yes, landing with the trimmer can be practiced, but in an actual emergency there are other factors and it's hard to estimate how much control we still have) $\endgroup$
    – vsz
    May 14 at 4:46
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    $\begingroup$ If the trim is by a tab like on a Blanik that can act as an external operating servo, and the elevator is free to move because the cable circuit is broken and the surface is loose, you'll be able to fly it perfectly well on trim. Some jets with non hydraulic flight controls actually work that way (eg, DC-9, where the control column itself works a servo tab, not the elevator surface directly). If it's a bungee spring up in the cockpit somewhere applying tension to the stick for you, it probably won't be of use unless the control circuit is still intact. You'll know soon enough when you try it. $\endgroup$
    – John K
    May 14 at 14:47
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    $\begingroup$ On that note -- of the difficulty in leaving a potentially controllable aircraft and feeling shame or fear of the destruction of the airframe -- the USAF has been training pilots since at least the 1980s that while the plane can be replaced, they cannot: don't delay the decision to eject. At least, according to this training film: youtube.com/watch?v=dyjYp6WT7ww $\endgroup$
    – Landak
    May 14 at 15:06

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