Flight Safety Australia article - duff gen
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Back in the days when we were actually allowed to take aircraft to the stall for training purposes - Cessna twinjets - and we were allowed to conduct the LPC/OPC in the aircraft, I was on a course in the USA. The FAA training assumed that the probability of a stall was greatest when the aircraft was close to the ground and in a dirty configuration. Height loss was a major consideration. The recovery from the incipient stage was to apply full power, hold the pitch attitude and keep wings level with aileron. Get rid of drag flap and gear up with a positive rate of climb.
A few weeks later when I was doing my TRE renewal with a CAA examiner on board, I demonstrated the FAA recovery to the 'student'. The CAA examiner was horrified!! **** scared more likely! Apparently I should have pushed the control column forward to unstall the wing and then increased pitch attitude and not used any aileron until the aircraft was climbing away at a safe speed. When I suggested that we would have hit the ground using this procedure he failed my check ride and I had to take the test again at a later date. A completely different thinking process from two of the major licensing authorities.
A few weeks later when I was doing my TRE renewal with a CAA examiner on board, I demonstrated the FAA recovery to the 'student'. The CAA examiner was horrified!! **** scared more likely! Apparently I should have pushed the control column forward to unstall the wing and then increased pitch attitude and not used any aileron until the aircraft was climbing away at a safe speed. When I suggested that we would have hit the ground using this procedure he failed my check ride and I had to take the test again at a later date. A completely different thinking process from two of the major licensing authorities.
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Ideally the stall should be detected at the incipient stage, in which case the stall recovery you described would be correct. However once the aircraft has stalled you don’t want to use aileron as the controls may well work in the reverse sense. As for pushing the control column forward, no, it’s just meant to be sufficient to unstall the wing, and in most training aircraft this will only be a couple of centimetres. The last thing you want is to pole the control column all the way forward.
It would seem that the FAA has moved on from that theory too, now their focus is on properly breaking the stall rather than the height loss aspect.
It would seem that the FAA has moved on from that theory too, now their focus is on properly breaking the stall rather than the height loss aspect.
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Well this is what the CASA Flight Training Manual says:
RECOVERY WHEN THE WING DROPS
Use the standard recovery, i.e. simultaneous use of power and forward movement of the control column. In addition rudder must be used to prevent the nose of the aeroplane yawing into the direction of the lowered wing. The ailerons should be held neutral until control is regained, when the wings should be levelled.
The thinking here is to provide a consistent safe recovery and to prevent entry into a spin.
Note the use of rudder is to prevent further yaw, not to “pick up the dropped wing”. The ailerons should be held neutral until the wings are un-stalled, otherwise trying to “pick up” the low wing with aileron will further increase the angle of attack of the low wing and further aggravate the undesired roll tendency.
RECOVERY WHEN THE WING DROPS
Use the standard recovery, i.e. simultaneous use of power and forward movement of the control column. In addition rudder must be used to prevent the nose of the aeroplane yawing into the direction of the lowered wing. The ailerons should be held neutral until control is regained, when the wings should be levelled.
The thinking here is to provide a consistent safe recovery and to prevent entry into a spin.
Note the use of rudder is to prevent further yaw, not to “pick up the dropped wing”. The ailerons should be held neutral until the wings are un-stalled, otherwise trying to “pick up” the low wing with aileron will further increase the angle of attack of the low wing and further aggravate the undesired roll tendency.
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It does depend on the type of aircraft though. On a swept wing the stall starts on the inboard wing and then moves outboard as speed decreases. When light buffet is encountered the outboard wing is not stalled and the ailerons will function normally. Use of aileron at this stage is the best action.
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It does depend on the type of aircraft though. On a swept wing the stall starts on the inboard wing and then moves outboard as speed decreases. When light buffet is encountered the outboard wing is not stalled and the ailerons will function normally. Use of aileron at this stage is the best action.
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It does depend on the type of aircraft though. On a swept wing the stall starts on the inboard wing and then moves outboard as speed decreases. When light buffet is encountered the outboard wing is not stalled and the ailerons will function normally. Use of aileron at this stage is the best action.
on Boeing swept wing jets, the procedure is to un-stall the aircraft first, THEN ROLL. The QRH is very explicit about not attempting to roll while encountering buffet ( or stick shaker)
Still differences between CAA and FAA per this interesting document https://bura.brunel.ac.uk/bitstream/.../Fulltext.docx
https://www.faa.gov/documentLibrary/...C_120-109A.pdf
..In my 3 decades as a flight instructor, I have been lucky enough not to witness any serious accidents, but unfortunately, have lost several colleques to them..1 to VMC-roll after an engine failed in a twin, 1 attempted a turn back after engine trouble in a single-engine plane, 1 broke both wings off his plane during a training flight, just to mention some..All these were in situations, that we train for, but for some reason the outcome was what is was..
..Now to the point..To my knowledge, there is only one way to recover from a stall, in any kind of an airplane..If you know another way, feel free to explain..As flight instructors, we try our best to teach our students, to avoid stalls (and other mistakes), especially when you are down at low altitude..That´s because you may only get one chance, if any, to regain control of the plane..
How to recover from a stall ??..I think you know the answer..
Fly safe,
B-757
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Well this is what the CASA Flight Training Manual says:
RECOVERY WHEN THE WING DROPS
Use the standard recovery, i.e. simultaneous use of power and forward movement of the control column. In addition rudder must be used to prevent the nose of the aeroplane yawing into the direction of the lowered wing. The ailerons should be held neutral until control is regained, when the wings should be levelled.
The thinking here is to provide a consistent safe recovery and to prevent entry into a spin.
Note the use of rudder is to prevent further yaw, not to “pick up the dropped wing”. The ailerons should be held neutral until the wings are un-stalled, otherwise trying to “pick up” the low wing with aileron will further increase the angle of attack of the low wing and further aggravate the undesired roll tendency.
RECOVERY WHEN THE WING DROPS
Use the standard recovery, i.e. simultaneous use of power and forward movement of the control column. In addition rudder must be used to prevent the nose of the aeroplane yawing into the direction of the lowered wing. The ailerons should be held neutral until control is regained, when the wings should be levelled.
The thinking here is to provide a consistent safe recovery and to prevent entry into a spin.
Note the use of rudder is to prevent further yaw, not to “pick up the dropped wing”. The ailerons should be held neutral until the wings are un-stalled, otherwise trying to “pick up” the low wing with aileron will further increase the angle of attack of the low wing and further aggravate the undesired roll tendency.
What I don't understand about this conversation is which 'myth' the OP is trying to skewer. Is the 'old wives tale' the idea that the ailerons will be ineffective in a stall, that you should use opposite rudder when a wing drops, or something else? I'm not necessarily critical of modern methods or of anyone who does things differently than I was taught, but I think that different perspectives may come from a different understanding of the phases of flight as well as significant differences in how airplanes perform. Even in the SEL less-than-250HP general aviation classification there are big differences that would affect the issues here. Some aircraft can develop very high sink rates without being fully stalled, so the ailerons still work. Others do not behave this way, and using ailerons will put you in a very bad state very quickly.
Just for reference, I'm a mid-to-low time pilot that has flown at least 7 different types that sort of encompass the range of the small single engine category. My training included things like full stalls, spins of three turns, engine-out to a full-stop landing and after PPL, things like tailwheel, floats and even (once) skis. I even went for some aerobatic training with inverted spins. I realize that many of these things are not practical or encouraged today, but when I hear people claiming that you can safely control a stalled airplane indefinitely, including aileron usage, all I can visualize is the smoking wreck where they've spun in turning base to final on a gusty day. Someone trained the way I was would know better.
There may be good reasons for some of the more modern methods, and the story by PaulH1 illustrates one pretty well--in order to survive a low-level stall such as the classic base-to-final spin, you need to catch it much earlier. In a single-engine Cessna, if the left wing suddenly drops sharply and the plane yaws 90 degrees left, someone with my training will recover quickly and efficiently without breaking a sweat because we've done it before. Unfortunately, in many cases the ground will intervene before we're finished. Someone who is terrified of actual stalls and has never, ever done a spin recovery will be almost as well off because in this case, your survival depends on dealing with an incipient stall, not a full one. Perhaps it is best to concentrate training energy there. However, that doesn't justify dismissing other techniques or training as "old wives tales".
Two points.
Yes the inboard section of a swept wing jet ( indeed all wings) stall at the root first, a desirable stability requirement which gives a nose down pitch at the stall.
However, how do you know how much of the wing is stalled, so assume the worst and avoid the use of aileron until unstalled.
Secondly, after 20 years p1 on various Boeing rwins I dont really buy this business of pitch changes with power being dominant or making things difficult.
Adding power at recovery does reduce height loss, essential for recovery near the ground !
Yes, it does occur BUT the elevator can so easily control the required pitch attitude, so is the primary control, fly the aircraft, dont let it fly you !
That said, perhaps FBW Airbuses are different !
Back in my box !
Yes the inboard section of a swept wing jet ( indeed all wings) stall at the root first, a desirable stability requirement which gives a nose down pitch at the stall.
However, how do you know how much of the wing is stalled, so assume the worst and avoid the use of aileron until unstalled.
Secondly, after 20 years p1 on various Boeing rwins I dont really buy this business of pitch changes with power being dominant or making things difficult.
Adding power at recovery does reduce height loss, essential for recovery near the ground !
Yes, it does occur BUT the elevator can so easily control the required pitch attitude, so is the primary control, fly the aircraft, dont let it fly you !
That said, perhaps FBW Airbuses are different !
Back in my box !
Last edited by RetiredBA/BY; 23rd Feb 2020 at 09:32.
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However, how do you know how much of the wing is stalled, so assume the worst and avoid the use of aileron until unstalled.
It is a matter of feel. On the military jets of the 70/80s, the F4 Phantom and the Lightning any max rate turn required flying in the buffet. Too much and the drag increased too much and you stopped turning. Too little and the turn radius increased. It starts with light buffet and gradually gets heavier. Not much to do with the original question I admit but in the Phantom light buffet had to be pulled on the finals turn as the wing did not work too well at low speeds!
It is a matter of feel. On the military jets of the 70/80s, the F4 Phantom and the Lightning any max rate turn required flying in the buffet. Too much and the drag increased too much and you stopped turning. Too little and the turn radius increased. It starts with light buffet and gradually gets heavier. Not much to do with the original question I admit but in the Phantom light buffet had to be pulled on the finals turn as the wing did not work too well at low speeds!
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Simultaneously apply full power, reduce the angle of attack sufficient to unstall the wing, and opposite rudder sufficient to prevent further wing drop (prevent further, not return to wings level).
Once the wing is unstalled level wings with aileron and recover from the nose low U/A.
If you use rudder to level wings at the stall you run a good chance of entering a spin.
Once the wing is unstalled level wings with aileron and recover from the nose low U/A.
If you use rudder to level wings at the stall you run a good chance of entering a spin.
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The purpose of applying rudder during a wing drop stall, is not to “prevent further wing drop” as stated above.
the purpose of the rudder is to stop the yaw towards the low wing. Stall + Yaw = Spin.
the purpose of the rudder is to stop the yaw towards the low wing. Stall + Yaw = Spin.
I think this really depends what sort of plane you’re flying, what altitude you’re at and what the flight manual says to do. It also depends how deep you are in the stall. The stall warning tends to go off about 10kts above the stall in the 172 for example and that thing can be treated like rubbish (do everything wrong) in around and beyond the stall and is unlikely to kill you (depending on altitude) , but there is another reasonably popular trainer that has the tendency to go into flat spins and drastic height losing stalls - certain news grabbing schools have recently been advised to stop doing these training sequences in these aircraft as they may not have correctly passed certification to practice these sequences .
Regardless , I feel there may be some wording issues in this thread between stalls and spins, but let’s just say that somehow both aerofoils were in a deep stall , and you started using aileron (while still holding back pressure) when you sensed a wing drop it would deepen the stalled state by increasing the relative AoA.
When you teach this stuff, it tends to be a sensory overload initially to the student and you’d be surprised how many pilots I’ve trained who were scared or very wary of the stall. Even experienced ones. But in teaching it, you need to be able to formulate it into a package that’s going to get through in this time and be something that will save them as they come back into their first solo . People do strange things they wouldn’t normally do when they’re under stress, and stall training is no different. I guess sometimes the wording may seem wrong from some instructors, but you don’t want an inexperienced pilot shoving in a bucketload of aileron to correct an approaching or developed stall. They need to see and recover from the symptoms to meet the criteria - for better or worse I think most people understand by the time they need to.
I used to take instructor trainees up and show them what it looked like to do everything wrong. And then let go. Most trainers will fix themselves.
Regardless , I feel there may be some wording issues in this thread between stalls and spins, but let’s just say that somehow both aerofoils were in a deep stall , and you started using aileron (while still holding back pressure) when you sensed a wing drop it would deepen the stalled state by increasing the relative AoA.
When you teach this stuff, it tends to be a sensory overload initially to the student and you’d be surprised how many pilots I’ve trained who were scared or very wary of the stall. Even experienced ones. But in teaching it, you need to be able to formulate it into a package that’s going to get through in this time and be something that will save them as they come back into their first solo . People do strange things they wouldn’t normally do when they’re under stress, and stall training is no different. I guess sometimes the wording may seem wrong from some instructors, but you don’t want an inexperienced pilot shoving in a bucketload of aileron to correct an approaching or developed stall. They need to see and recover from the symptoms to meet the criteria - for better or worse I think most people understand by the time they need to.
I used to take instructor trainees up and show them what it looked like to do everything wrong. And then let go. Most trainers will fix themselves.
The purpose of the rudder is to maintain balanced flight.
What I look for in a stall recovery at flight test is that as power is applied any yaw is prevented.
What I look for in a stall recovery at flight test is that as power is applied any yaw is prevented.
Thread Starter
If you use rudder to level wings at the stall you run a good chance of entering a spin.
While this writer has experienced severe wing drops in older military types, even the DC3 can surprise you if stall practice is entered too harshly in the landing configuration. By ‘harshly’ I mean faster than the usual reduction of one knot per second until the stall occurs.
By far the worse aircraft I encountered was a certain Cessna 152 owned and maintained by an LAME. Like the Cessna 172, the Cessna 152 has a benign stall. On this occasion during a practice clean stall, the left wing dropped rapidly and quite unexpectedly. While the usual recovery was initiated (sufficient rudder to stop the yaw towards the dropped wing and nose down elevator), this aircraft yawed and rolled so quickly that 4-800 feet was lost in recovery with the aircraft recovering 180 degrees in the opposite direction to the original heading.
The same problem happened with the full flap stall recovery - only worse -and the flaps had to be retracted quickly to avoid exceeding flap speed limitation. This aircraft could have been a danger to any pilot inadvertently holding off too high during landing.
Following the write up of this defect in the maintenance release, an investigation revealed mis-rigging of the left wing. Once that was rectified, the benign stall characteristics returned to normal.
The lesson here was that although most flying school aircraft have benign stall characteristics, an occasional ’rogue’ aircraft can slip through the system. In this case, the rogue was well known among the instructors who flew and trained ab-initio students on it. Yet no one bothered to write up the snag. An unspoken proviso among the instructors was that solo ab-initio flying on that aircraft was not permitted because of its unhealthy stall characteristics
It follows that if an aircraft you are flying has worrisome handling characteristics, then when in doubt write it up in the maintenance release. The operator should fix the problem before further flight. If nothing else, it warns the next pilot who flies that aircraft rather than leave him to cop an unexpected problem.
Last edited by Centaurus; 23rd Feb 2020 at 03:30.
The only way to recover from a stall is to reduce the angle of attack. Specific guidance for each type in stall recovery is listed in the AFM.
. The use of thrust when stalled can interfere with the pitch control and prevent recovery.
What is important is to regain safe maneuver speed as quickly as possible - especially if the aircraft is still in severe turbulence. Application of climb or maximum continuous thrust at the same time as the nose is lowered to un-stall the wings, helps to achieve a more rapid acceleration towards severe turbulence penetration speed.