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My understanding is that sailplanes usually have the pilots wear the parachute on their back, requiring the pilot to bail out of the aircraft before they can use the parachute.

Given the maturity of modern whole-airplane ballistic parachute technology, this seems strange to me given the drawbacks of having to bail out: it takes time, ability to bail can be affected by G forces, presumably requires some parachuting skill, and is not really a solution for unskilled passengers.

There are even airbag solutions like DG Noah that help pilots bail out of the sailplane.

So, why aren't sailplanes equipped with ballistic parachutes, given how popular these systems are becoming on various ultralight aircraft? Does something about the sailplanes' construction or performance parameters make this type of aircraft a poor fit for whole-airplane parachutes?

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    $\begingroup$ I wonder what you are trying to fix? A glider can by definition already glide very well, so why would you need a system that makes the aircraft glide towards the ground without any pilot control? The Cirrus planes only have the parachutes for spin recovery. $\endgroup$
    – Bianfable
    Commented Sep 1, 2021 at 8:37
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    $\begingroup$ @Bianfable probably 90% of single seater glider pilots wear parachutes. The midair collision risk is high and in my experience is the biggest risk in soaring. $\endgroup$
    – John K
    Commented Sep 1, 2021 at 13:03
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    $\begingroup$ @Bianfable yes exactly. At a glider club on a busy afternoon you are on intense traffic alert the entire time. I've had a few close calls over the years. FLARM, the poor man's TCAS system, is extremely popular in the soaring world. My club has it installed in all club a/c and just about all the private owners have it. Parachutes tend not to be worn on 2 seat training flights however; the average passenger won't be able to use it properly.I can see a ballistic system being adopted on 2 seaters but not on singles where you normally wear a parachute all the time and the seat is designed for it. $\endgroup$
    – John K
    Commented Sep 1, 2021 at 14:39
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    $\begingroup$ I guess adding a parachute adds responsibility (in case of defective deployment) and certification costs for the manufacturer, while individual parachutes are pilot business. In addition individual parachutes may allow a better control of the landing site, at least for trained users. $\endgroup$
    – mins
    Commented Sep 1, 2021 at 15:50
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    $\begingroup$ I would just as soon leave the a/c with a parachute on my back than ride down in the glider with one. I have witnessed a midair between two gliders right near the field, abt 20 yrs ago, and one guy was saved because the glider disintegrated around him and he had not much choice but release the harness to free himself from the fuselage pod and pull the ripcord to stop plummeting.The other guy had semi-control of his glider and tried to fly it, but lost control eventually and went straight into the ground and was killed. I'm an ex jumper and likely would have less inhibition about bailing out. $\endgroup$
    – John K
    Commented Sep 1, 2021 at 17:26

3 Answers 3

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why aren't sailplanes equipped with ballistic parachutes?

Because of their longevity. Most were built or designed before full-airplane parachutes were a thing. When Ballistic Recovery Systems started, their initial offering was for ultralights only. This makes sense because the limited speed range of ultralights makes the parachute simple.

Higher top speeds mean that the parachute needs to unfold in stages so the forces are limited and deceleration is gradual. This is achieved with first a small extraction chute or a rocket which pulls the main parachutes from their compartment. Those are partially sewn so they unfold only partially first. Next, the stitching is torn open gradually to draw out the full opening of the main chute(s).

Compare that to a conventional parachute which is only opened when the pilot has separated from the glider and has decelerated already enough so the parachute design can be much more simple. The glider cockpits are designed for pilots wearing a chute (see CS 22.785 (c)) and the fuselage is kept as small as possible, so the retroactive installation of a much more bulky full-airplane parachute is not possible. Note that the parachute also needs to be fixed to suitably strong attachment points. This means a complete redesign of the center fuselage. Doing this to an existing glider is simply not worth it.

To incorporate a full-airplane parachute needs the development of a new parachute together with the airplane. This has happened first with the SB-13 experimental flying wing glider in 1988. You cannot simply slap an existing chute to an arbitrary glider. This glider-parachute combination now must be certified against regulations which do not yet cover full-airplane parachutes. Given that glider manufacturers are mostly small, privately held companies, most shy away from the expenses involved.

You may also say that market pull is not strong enough. If everyone would be clamouring for their own full-aircraft parachute, someone would have started to offer new designs with them. So far, the market demand simply isn't there.

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Opposing viewpoint: BRS are already used in gliders

The AC-4C and Phoenix both have models with a fuselage mounted BRS. I'm sure others do as well, I'm simply not familiar with them.

I wear a parachute when I fly, but I would much rather have a BRS. It's hardly any heavier but it is much, much more useful, IMHO. A BRS can be triggered from within the safety of the cockpit, and requires much less coordination. It also works from far lower altitudes, and the repack requirements are far less onerous (although repacking a BRS is much more expensive). I also suspect it results in fewer injuries, as there is no chance of getting hurt while exiting the glider and the ground impact is cushioned by the fuselage.

As to why all manufacturers don't offer BRS on all modern planes, I can't give any facts, only guesses (which is not really appropriate for Aviation.SE). For starters, BRS is relatively new on the scene, and due to the extremely small production volumes and tight finances gliders aren't hotbeds of innovation.

It might also have to do with the fact that many planes have water ballast, which has a huge impact on the overall weight. A plane with 500kg of water might need an impractically large parachute.

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  • $\begingroup$ Are they usable (safety-wise) after a collision and losing a wing? I'd imagine the remaining wing will roll vertically down and impact first followed by an unarrested impact of the cockpit. $\endgroup$
    – user14897
    Commented Sep 1, 2021 at 20:32
  • $\begingroup$ I've never had occasion to use one so couldn't say! I might not be fully informed about the problem, but I consider rolling as a "not-bad" result. In my mind, it means the plane will decelerate more gently. The parachute will prevent the plane from falling uncontrollably. $\endgroup$
    – Kenn Sebesta
    Commented Sep 1, 2021 at 20:36
  • $\begingroup$ I concur that some sailplanes do use BRS, but those are clearly in the minority. Vast majority seem to use pilot-worn parachutes. $\endgroup$
    – Nikita
    Commented Sep 1, 2021 at 22:33
  • $\begingroup$ @Kenn Sebesta rolling may be far from not bad. Speaking as a paraglider pilot (a glider technically but far removed from a sailplane) the primary concern after reserve deployment is to stop the main wing from interfering with the parachute. Downplaning and rotation can result in high descent rates and deflation of the parachute. $\endgroup$
    – Frog
    Commented Sep 4, 2021 at 20:47
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    $\begingroup$ @ Kenn Sebesta you’re right. I can imagine that a sailplane that’s been involved in a mid-air might have a considerable tendency to roll uncontrollably and exiting it might be a good idea. Agreed, rotation after first contact with the ground is generally a minor concern. $\endgroup$
    – Frog
    Commented Sep 5, 2021 at 6:54
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BRS chutes weigh a lot. From a cursory google search, they range from 30 to 100 pounds- 30 pounds is light enough that you could lift it if you’re an average human being, but it’s not insignificant. Glider manufacturers and pilots try to shave every possible bit of weight off the aircraft. While there’s enough risk to wear a parachute, most pilots will not have to bail out of their aircraft at any point in their flying career. Now, in the small group of pilots who have to exit the aircraft, how many of those will be in a situation where they cannot jump out? A whole-airframe parachute would be great for safety, but it’s also another potential point of failure- it could go off unintentionally, but it could also just not deploy when you need it. Pilots already wear parachutes and in most cases can get out. The reason BRS are not used is because there are better options.

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    $\begingroup$ Just for reference, for sailplanes BRS weight would be approx 25-30 lbs for a system like this galaxysky.cz/grs-6-600-sd-speedy-115m2-p20-en plus, as someone else pointed out, the necessary reinforcement to the sailplane's structure to support shock loads. $\endgroup$
    – Nikita
    Commented Sep 6, 2021 at 0:50

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