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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)

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    $\begingroup$ Actually, most of the initial flight training regarding spins is on recognition and avoidance, not recovery. Good question though! $\endgroup$ – Lnafziger Jan 8 '14 at 19:15
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    $\begingroup$ 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! $\endgroup$ – Lnafziger Jan 8 '14 at 19:23
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    $\begingroup$ 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. $\endgroup$ – casey Jan 10 '14 at 20:58
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    $\begingroup$ @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. $\endgroup$ – Philippe Leybaert Jan 10 '14 at 21:12
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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.

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    $\begingroup$ Unfotunately, Air France showed that they can still be stalled..... $\endgroup$ – Lnafziger Jan 9 '14 at 2:08
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    $\begingroup$ 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.... $\endgroup$ – Lnafziger Jan 9 '14 at 2:10
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    $\begingroup$ @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. $\endgroup$ – Shawn Jan 9 '14 at 14:54
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    $\begingroup$ Have you tried to spin at high altitudes like service ceiling? Is recovery more difficult there? $\endgroup$ – Andrius Feb 2 '16 at 14:25
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    $\begingroup$ @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. $\endgroup$ – Shawn Feb 3 '16 at 14:32
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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.

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    $\begingroup$ 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. $\endgroup$ – busdrivingtupperware May 17 '15 at 14:34
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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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    $\begingroup$ My question was specifically about spin recovery, not stall recovery/prevention. $\endgroup$ – Philippe Leybaert Jan 9 '14 at 2:01
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    $\begingroup$ How do you get into a spin. $\endgroup$ – Phil Fountain Jan 9 '14 at 2:35
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    $\begingroup$ The Colgan flight entered a spin after stalling. My question was if recovery is possible if you do get in a spin. $\endgroup$ – Philippe Leybaert Jan 9 '14 at 3:02
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    $\begingroup$ @Shawn And still they sometimes do manage to stall and spin a big airliner. Hence my question :-) $\endgroup$ – Philippe Leybaert Jan 9 '14 at 15:04
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    $\begingroup$ @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. $\endgroup$ – Lnafziger Jan 9 '14 at 15:31

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