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During initial flight training a lot of emphasis is placed on stalls and spins and how to recover from them, but is it possible to recover from a fully developed spin in an airliner? Do these large aircraft have enough rudder authority to pull it off?

Has it ever been done? And is it part of the training for specific type ratings? (in a simulator of course)

voretaq7
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Philippe Leybaert
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    Actually, most of the initial flight training regarding spins is on recognition and avoidance, not recovery. Good question though! – Lnafziger Jan 08 '14 at 19:15
  • Of course, but you're also expected to know how to recover from a fully developed spin. Although rather uncommon these days, some instructors still want you to demonstrate it during training (in a spin-approved aircraft of course). – Philippe Leybaert Jan 08 '14 at 19:20
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    Here in the US, actual spin training is only required for your flight instructor certificate. This may be different other places though. In any case, I was just nitpicking the first sentence. I'm curious about the answer myself! – Lnafziger Jan 08 '14 at 19:23
  • One of the reasons why I'm asking is because of a few famous stall/spin accidents involving airliners (Colgan Air 3407 for example) – Philippe Leybaert Jan 08 '14 at 19:26
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    Colgan Air 3407 was a case of a captain getting himself into incipient stall and then providing control inputs to put the plane into a full stall. That case has no bearing on the ability to recover from a wing stall, as the crew never attempted to do that. – casey Jan 10 '14 at 20:58
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    @casey Did you read the question? I asked if it is possible to recover from a fully developed spin, not a stall. I was just referring to Colgan 3407 to illustrate that airliners do stall, despite stick shakers and pushers. So it is not inconceivable that an airliner can enter a spin and I am simply asking if it is physically possible to recover if the airplane is already in a spin. How it got into the spin is not part of my question. – Philippe Leybaert Jan 10 '14 at 21:12
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    Interesting reads: http://www.pprune.org/flight-testing/226351-spinning-airliner.html and http://www.airlinepilotforums.com/hangar-talk/6370-spinning-airliner.html – Danny Beckett Jan 28 '14 at 07:20
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    I would say it depends of the airliner, but China Airline 006 tends to prove it is possible (even though I don't know if this could be qualified as a fully developed spin), at least for the B747SP. – Manu H Feb 02 '16 at 14:17
  • The problem with your question, which is an intriguing one, is that you'd need to ask this question for each model of aircraft. Depending upon design (such as the high tail of some previous airliner designs) even the stall characteristics (and chances for recovery) will vary from model to model. (Deep stall was potentially unrecoverable, for example). The other issue to consider is what control inputs are specifically "pro spin" control inputs for a given model. – KorvinStarmast Sep 27 '17 at 13:27

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There were a lot of other mitigating factors in the Colgan Air 3407 crash. Was that one recoverable? It depends. It never should have got to the point of a stall in the first place. It was more preventable than recoverable.

But in answer to your question, again, it depends. Every aircraft in the air can stall and be recovered, if responded to properly. But the plane may very well bend and break if the stall develops too far. Then it may not be recoverable. And most large airliners (or aircraft bigger than a few thousand pounds with multiple engines) aren't designed for the stresses of spins, so they never teach to a full stall. In those types of aircraft a full stall is much more dangerous, and they can be much more difficult to recover from, especially if you break something. Besides, in aircraft like that, you should receive plenty of direct warning long before you reach the point of a stall.

When I was teaching, stalls and spins were one of my favorite subjects for early pilots. Especially in light trainers like the Cessna 150/152s. Those aircraft were always incredibly good at stalls/spins and incredibly forgiving. You can put a Cessna into a hands-off full stall if you trim it right, and it will stop rotating in a spin if you simply let go of it (and have enough altitude). I always taught my students spin recovery from a full spin, even at the Private Pilot level. And usually shortly after teaching them full stalls. I would stall it, make it rotate at least 3 or 4 times, and have them recover the spin. Then have them do it themselves. I never had to worry about my students not knowing how to recover from an unintentional stall/spin. By the time my students were learning to fly multis, I was teaching them more stall recognition and avoidance than recovery. Recovery is essentially the same in all aircraft. You just have to be sure to not reach that point.

There's only one thing you really need with any aircraft in a stall/spin, and that's altitude. Unfortunately, takeoffs and landings are the most likely places for you to get behind the aircraft and let it unintentionally stall/spin. That's why you learn how to recognize them very early in your pilot training. You can't spin without a stall first, and just about any airplane will give you fair warning before you stall it. The trick is recognizing the situation before it becomes serious.

Shawn
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    Unfotunately, Air France showed that they can still be stalled..... – Lnafziger Jan 09 '14 at 02:08
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    Also (just my personal opinion here) I disagree with spin training in a Cessna just because it is so forgiving. People don't respect it the way that they should, because it is just so hard to spin that there is no way it could accidently happen, and even if it did you just have to let go.... – Lnafziger Jan 09 '14 at 02:10
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    @Lnafziger - It all depends on how you teach it. I always taught it more from the angle of "respect how easy it is to unintentionally spin" rather than "see how hard it is to spin this airplane". I liked spinning in the Cessna BECAUSE it allowed me to easily enter a full spin and hand the plane over to the student with the additional margin of error so that they couldn't do something to exceed MY ability to recover.

    That's the exact same reason I always hated stall training in a Piper Tomahawk. That plane was VERY easy to unintentionally spin. And it spun somewhat flat. That sucked.

    – Shawn Jan 09 '14 at 14:54
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    Have you tried to spin at high altitudes like service ceiling? Is recovery more difficult there? – Andrius Feb 02 '16 at 14:25
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    @Andrius No, I have not tried it. But I imagine recovery would be more difficult since the aerodynamics at higher altitudes are different, and controls will be less effective. – Shawn Feb 03 '16 at 14:32
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    @Lnafziger - I gave you +1 but differ slightly in some points. Cessna are not "easy" aircraft to spin train in (FYI also Piper tends to stall much softer then Cessna) All FAA (after CAR 3 - 1959) GA normal category aircraft are required to recover from a spin hands off within 1-1/2 turns. All small training aircraft exhibit this behavior. With the exception of older mostly rag and tube aircraft, Cessna aircraft have a more violent (wing drop) habit. When I had 10hrs and was getting my PPL in 1975 I switched from Piper to Cessna aircraft specifically because Cessna's are less forgiving. – jwzumwalt Dec 13 '17 at 04:30
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    @jwzumwalt Which Piper aircraft were you flying? In my experience, Cessnas were not "easy" to enter a spin, which is part of why I liked teaching in them. The Piper Tomahawk was the only aircraft I ever flew that unintentionally tried to spin in almost every stall. And when it did spin, it was very flat. That's not very fun. I definitely wouldn't classify any Cessna I ever flew as "less forgiving" than any Piper. – Shawn Dec 13 '17 at 14:57
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In the sixties a Sabena Caravelle VIN entered a flat spin during a training flight. The crew demonstated stall recovery in different configurations when the plane entered into a spin by accident. The instructor saved the aicraft by pulling the brakechute after configuration changes showed no result (the Caravelle VIN had no reverses on the RR Avons but was equiped with a brake parachute in the tailcone). The yaw decreased and the tail was pulled up enough to unstall the wing.The wing had only TE-flaps and no LE-slats.

Leo D'Hondt
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Yes they will spin.

They appear to have enough rudder authority - big twins have a lot, for engine-out reasons, but I don't know the aerodynamics well enough to state that it's certain to be enough, good question.

No, they have not been spun during test or for training. No, type-ratings don't include spin recovery, just stall recovery in simulators (including FBW types which have to be degraded first to allow them to stall) and recently recovery from unusual attitudes.

Simulators can't generally be used to train anything involving sustained yaw because the physical limitations make it impossible to accurately reproduce the feel. They are not built or approved to model accurately anything outside the approval requirement, which doesn't include spins, so while my large aircraft type's sim spins quite nicely ( I do it quite often, for fun, 'after hours' there's no guarantee, proof or reason to expect that the real aircraft would spin in the same way or be as recoverable.

kevin
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Busmanl
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    Most sims use predictive numerical integration algorithms which are only effective in linear phases of flight. In non linear phases (post stall), these algorithms break down very quickly. Not to mention, there often is no post stall data from flight testing for obvious reasons. The net experience in the sim is just an educated guess. In the case of AF447, the yaw damper function did a very effective job of minimizing sideslip and preventing the aircraft from entering a fully developed spin. – busdrivingtupperware May 17 '15 at 14:34
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Swept wing aircraft are equipped with yaw dampers to keep the aircraft in coordinated flight since swept wing aircraft are more susceptible to Dutch Roll (you can look up that term).

An American Airlines A300 lost its entire tail and spun out of control departing New York in 2001 as a result of a pilot using too much rudder pressure to (over) respond to what he thought was a wake turbulence encounter.

I'm no engineer, but if an airliner can exceed it maximum design limit on the vertical tail and lose the tail as a result of using too much rudder pressure, logic tells me that the vertical tails are absolutely not designed to take the stress of any kind of excessive rudder input (like you'd use for spin recovery), and in fact, the tail just rips off when you get sideways. (Note that Airbus aircraft have composite tails and there is a known issue with the A300 model having overly sensitive rudder pedals- and the pilot used A TON of pressure on the rudder pedal).

Swept wing aircraft are susceptible to dutch roll. Recovering from a spin in a swept wing aircraft? Well, it's kind of like a low altitude spin in a small airplane... if you didn't do your job as a pilot to prevent the approach to stall and ensuing stall... you missed your chance and you're done.

JetCityMatt
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Big airplanes of the jet types have what is called stick shakers to warn pilots of an approaching stall and a stick pusher to initiate a recovery. In training with jets most pilots do 100% of there training in simulators and then make three takeoff's and landings in the airplane.

T tail airplanes may not be able to recover from stalls if the airplane get into a deep stall because airflow over the tail is blocked by the airplane and the elevator becomes ineffective.

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    My question was specifically about spin recovery, not stall recovery/prevention. – Philippe Leybaert Jan 09 '14 at 02:01
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    How do you get into a spin. – Phil Fountain Jan 09 '14 at 02:35
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    The Colgan flight entered a spin after stalling. My question was if recovery is possible if you do get in a spin. – Philippe Leybaert Jan 09 '14 at 03:02
  • @Phil Fountain Maybe post that as a question to get a full answer. Short answer for a light aircraft: put it up into a power off stall, then at the moment of the stall jam the rudder in the direction you want to spin. – Terry Jan 09 '14 at 03:53
  • @Terry I think it was a rhetorical question. :) – egid Jan 09 '14 at 05:21
  • With big aircraft the systems I discussed are used to prevent both situations from happening. The are both interrelated. – Phil Fountain Jan 09 '14 at 13:39
  • @Philippe - Again, it all depends. Under perfect conditions, you SHOULD be able to recover. But if you've already reached a point where you're spinning a large airliner, you're already so far behind the game that you probably won't be able to catch up fast enough to recover. That's why the training tends to focus more on avoidance than on recovery. There's more than enough warning on any aircraft that you shouldn't spin it in normal operations. And if you're flying right, you really shouldn't even come close to a stall. – Shawn Jan 09 '14 at 15:00
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    @Shawn And still they sometimes do manage to stall and spin a big airliner. Hence my question :-) – Philippe Leybaert Jan 09 '14 at 15:04
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    @PhilFountain As I mentioned in a comment above, even with all of those systems in big aircraft, Air France still managed to stall one... :( It can happen. – Lnafziger Jan 09 '14 at 15:31
  • @Philippe - I would stand by my statement. Airplanes don't just stall under normal operations. So they can't spin either. And if you ever find yourself in a situation where you're stalling/spinning a large airliner, while it should be possible to recover, if you're that far out of the envelope that you allowed it in the first place, you may not be able to catch up fast enough to recover. – Shawn Jan 09 '14 at 15:59