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Ballistic Recovery Systems (wikipedia.org)
43 points by verandaguy on March 21, 2014 | hide | past | favorite | 30 comments


I worked for a while in the Flight Test department at Cirrus Aircraft, the manufacturer who is probably best known for these systems (all planes they manufacture come with them). The picture on the right side of the Wikipedia page is of one of their first tests of the system. The test pilot who did that exact pictured test told me that it was a pretty exciting experience; they had done all the calculations and static load tests possible, but they couldn't be sure exactly what would happen until the 'pulled the handle' for the first time. The parachute straps could have pulled out of their mounting points, the parachute could have failed to fully inflate or gotten tangled on the empennage, etc. The test pilot had to wear his own parachute in case things went badly and he had to bail out of the plane (the test plane had a special system to blow the doors off to facility emergency egress). Happily it worked well, although the deployment is a little bumpy :) The chute system has a mechanically-activated rocket that busts out a panel over the chute tube which is intentionally weakly mounted, and then proceeds to pull the uninflated chute fully out through the open hole about 100 feet, and then there's a special 'slow-inflation' ring on the chute rigging to slow down the inflation of the chute so that it doesn't put excessive force on the chute mounting and/or hurt the passengers. To prevent serious injury to the passengers when the plane hits the ground (it's still moving at a good clip), the seatbelts have airbags and the base of the seat is a few inches of aluminum honeycomb to absorb energy. The landing gear and wings are also designed to fracture/crush in a way that reduces the amount of force transmitted to the passengers. Although it's not uncommon to walk away with broken limbs or some sort of back pain, it's better than the alternative :) Cirrus is currently working on a Very Light Jet, the 5-person + 2kid Vision SF50 (http://cirrusaircraft.com/vision/) which also has a parachute - but it's a lot bigger than the ones on their existing 4-person SR-20/22 prop planes! I can try to answer any questions as best as I can remember...


I have a somewhat off topic question about airplane companies' attitude towards engines. As a private pilot who flies Cirruses, it's always baffled me that a FADEC is not standard equipment. For non-pilots, starting a plane requires priming the engine by injecting fuel into the lines, and fiddling with the fuel/air mixture until the engine fires. Totally different from a modern car where a computer electronically controls the injection to get the engine started almost immediately. Is the attitude in the industry still that FADECs are dangerous because of bugs/malfunctions? Or is it more of a certification issue?


Well the new jet has dual FADECs, so you can solve your problem by buying one of them :) I think that for the piston plane market, it's more of a cost/value ratio issue - would you (and customers in general) be willing to pay an extra $50-100k for a FADEC-equipped plane that costs $500k for the whole rest of the plane, just to have the convenience of eliminating manual mixture control? Also some pilots don't want to give up having the ability to control engine temp, power, fuel burn rate, etc manually using the mixture. I know that FADEC-equipped engines have been tested, and will probably be available in the future, it's more of a question of marketing and costs (certification etc) than anything technical.


Fellow Cirrus owner here. My assumption has always been the deterrents are cost (both development and production; many fewer engines to amortize over) and reliability (if you lose all electrical power in a FADEC system, the engine dies; not so with magnetos).


For FADECs on single engine piston planes, in addition to being powered by either alternator automatically, there's usually a dedicated FADEC emergency battery good enough for 1+ hours of engine runtime.


Of course. I stand by my original statement, however.


Understood :) As a fun note, i just remembered that the emergency FADEC power on the turbine engines is provided by a tiny hydro generator powered by the fuel flow itself, so it can run in case of total electrical failure. The throttle position sensors are energized by the same emergency circuit so they continue to work too :)


I'm taking flying lessons, and the Flight Design CTLS I'm in has one of these systems. I believe you can use it up to like 80 knots or more. I have to remember to take the pin out at the end of the run up, and back in when shutting down.

When they first came out, there was some reports that they they caused just as much loss of life as they prevented, but I think the stats are now in favor of them. They're not really meant to protect the plane but the pilot and passengers.

As far as a rule of thumb I think my instructor said that once something goes wrong in flight, it's the insurance company's plane, so just try like hell to survive and forget about aircraft damage. There have also been many incidents where the chute was used, and the plane eventually flew again.


As I was told when taking flight lessons and being introduced to this system, it's a device of absolute last resort, since you lose all control of the aircraft once you pop that chute. There's a lot of emergencies you can handle without having to pop the chute in an aircraft. Sadly, there are also a lot of emergencies where a chute would do you no good (such as stalling on approach or take off, the two phases of flight where most (56%) of crashes occur).

Fascinating tool though, and if I purchased a plane, I wouldn't mind having one for those "just in case" times. Of course, aircraft with this installed are generally over $200,000 new, so it's not on my radar anytime soon.


I think where BRS shines is that it helps flight in situations where the risks were otherwise too great. Flying day VFR over prairie is pretty survivable if you have an engine out, but the chances of getting through a situation like that while flying at night, in IFR, over mountains, VFR OTT, through known icing, etc., is much lower.

Light multi-engine aircraft were born for those situations but, ironically, they're not much better than single engine aircraft for survivability. There's a saying that a twin just gets you to the scene of the accident faster.

So, yeah, it's not a panacea, but improving the odds of living through the other 44% of flight accidents is still a good thing.


> Flying day VFR over prairie is pretty survivable if you have an engine out, but the chances of getting through a situation like that while flying at night, in IFR, over mountains, VFR OTT, through known icing, etc., is much lower.

Not trying to put words in your mouth but interestingly, this comment highlights one of the hazards of this system. It can give people the confidence to do things they should absolutely avoid doing and KNOW they should avoid doing. Things like a new and more effective wing deicer sometimes have a similar effect.


Yeah, pilots should know what they're getting into and be aware if it exceeds their experience. I didn't mean it to be an endorsement of unsafe behavior.

If the capabilities of the airframe and the pilots skill are sufficient for the conditions, like if your plane is certified for flight into known icing conditions and you have experience doing so, then it's not a huge risk to fly into these situations.

But if your plane has pneumatic deicing boots that require engine power and your engine quits, you may be in over your head in a hurry if ice starts building up while you're trying to perform an emergency landing.

In that situation it would be nice to be able to just pop the chute.


> like if your plane is certified for flight into known icing conditions and you have experience doing so, then it's not a huge risk to fly into these situations.

But it's not a binary condition such that you can make a really clear distinction like that, right? That seems like the big risk to me. If it were as easy as "those are icing conditions but we have to equipment to deal with icing conditions," okay, no problem.

I expect the risk assessment process involves more variables and is more along the lines of: "sure, that weather system is more dangerous than we'd ordinarily fly into but we've got a better deicer this time, we're in a hurry, we're experienced pilots so... let's do it." (admittedly, I have no idea how specifically a weather system's risk and a deicer's performance can be quantified beforehand... maybe it's a piece of cake)


> It can give people the confidence to do things they should absolutely avoid doing

This is a popular criticism of the system for which supporting evidence is never provided. I'm not saying it doesn't have this effect, but I see no reason to assume it does, any more than having seatbelts in a car makes you a more reckless driver.


> This is a popular criticism of the system for which supporting evidence is never provided.

You'd have to have read all the criticism of the system to be able to make this claim.

The Cirrus SR22 is worthy of study if you're actually interested in this. For a while at least, it had a somewhat poor safety record in spite of being in quantifiable terms an amazingly safe plane. I'm pretty sure human behavior is involved.

Anyway, here's a place you could start, although I can't vouch for the quality of an article I haven't read: http://www.avweb.com/blogs/insider/AVWebInsider_CirrusSafety...


> You'd have to have read all the criticism of the system to be able to make this claim.

Fair enough: This is a popular criticism of the system for which I've never seen any supporting evidence provided, including in this thread. Hunches and suspicions don't qualify.


A counterexample is welcome. The Cirrus SR22 has a somewhat mediocre safety record, in spite of its absolutely cutting-edge safety features, because...

Seriously. Insert content here. I see from your other comments that you've got one of these, so seriously, you must have some actual thoughts on this.


If you can't safely land in the event of an engine failure, shouldn't you not make the flight, even with a BRS?

It's always good to have more options available, but you shouldn't necessarily base your decision making on them. If the risks were too great for such a flight without a BRS, they really should be considered too great with it.


If I ever buy a light GA plane, I'd love to have something like this for additional safety. Unfortunately in GA, there are a lot of safety innovations which never get implemented, due to strict regulations and cost. Things like un-stallable/un-spinable airplanes (like the Ercoupe or the Long-EZ), could potentially make the dreaded spin on the base to final leg non-existent, but they aren't mainstream because they're too expensive to bring to market.

It's kind of a catch-22; people are afraid of flying because of safety issues, but you need scale to spread the costs of making planes safer.

*edit: corrected typo


Seems to me that the main things keeping people away from GA flying are cost, accessibility, impracticality, and lack of interest.

Which is to say: GA is painfully expensive (how many people are going to start a hobby that costs $150/hour?) hard to find (how far away is your nearest local airport that offers basic flight training?) useless (how many people are going to get to the point where they can travel for business or vacation using their own airplane?) and not something people care about too much anyway (flying is seen as boring).

I'm not aware of many people who want to get into GA but don't because they're scared of it. I have seen a lot of people leave or simply never pursue it because of the rest, though.


There are some videos of these in use; they are very effective when used within the chute's operational parameters: when the airplane is at altitude and moving at an appropriate (not too fast) speed, particularly over harsh terrain.

However, like all emergency devices, they are not a panacea. They don't protect against one of the most common fatal GA accident scenarios: loss of control at low altitude (base/final turn when landing). In that case, there is not enough time for the parachute to inflate before the airplane hits the ground.

I'm all in favor of BRS being available as options and after-market STCs on all small airplanes, but we also need to make sure emergency training isn't reduced to just "pull the chute", since there's a lot that can still go wrong outside of the chute's operational parameters.


Agreed - the 'chute seems like a fringe case for sure.


This particular standard feature has been a huge selling point for Cirrus, makers of a very nice, very expensive, high performance aircraft that has been heavily marketed toward wealthy, low time pilots that in many instances have no business being at the controls of such a challenging airplane. There is an argument to be made that this feature has created overconfident pilots that use the chute as an excuse for making otherwise poor or dangerous go/no-go decisions in the face of weather, terrain, etc. Cirrus' accident rate has been higher than the average for comparable aircraft, and it probably doesn't help that they used the chute as an excuse to skip proper spin testing of the aircraft.


> marketed toward wealthy ... pilots

Should they be targeting the poor ones with their "very expensive" aircraft?

> low time pilots

Can you provide ANY evidence that Cirrus targets "low time pilots?" Of course, the customer's insurance company has some say in this, too.

> There is an argument to be made that this feature has created overconfident pilots ...

Sure, but, again, where's your evidence?

> it probably doesn't help that they used the chute as an excuse to skip proper spin testing of the aircraft.

??? The SR20 was spun 60 times, with 60 recoveries, as part of European certification: https://www.cirruspilots.org/copa/safety_programs/m/copa_saf...!


The issue is that Cirrus is marketed as a personal transportation vehicle to people who aren't already pilots.

If you look at the accidents, there are quite a few head-scratchers (pilot gets lost and deploys BRS, or pilot gets disoriented in IMC and deploys BRS). It's not just one or two, but quite a lot like this. The Cirrus seems to be the new doctor killer.


I've always been shocked about the danger of general aviation. I always see needless deaths, and it makes me nervous. I would love to pursue this as a hobby, but stories like this:

http://www.wbir.com/story/news/2014/02/03/fire-chief-no-surv...

make me think we need a ballistic recovery system.


I'm surprised nobody has linked a very famous deployment of a ballistic parachute: https://www.youtube.com/watch?v=JXQKaxp6Rlk

In the above video, a pilots propeller hits another aircraft's glider towline which then wraps itself around the prop and engine disabling it.

I'm not a pilot, but this probably would have been fatal if it wasnt for the BRS.


I don't see why that would have been fatal without a BRS. Shut the engine down (if it's still doing anything after that much abuse) and glide to a landing somewhere.


From a physics point of view, how would this scale up to commercial jets? Presumably you would need multiple parachutes to distribute the load, but still, how large would they have to be to support that weight?


How about Star Wars-style escape pods or parachutes for each passenger row?




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