Practice stalls- when to recover?

[Whirlybird]

Hi everyone. As many of you know, I'm helicopter hours building in the US, but I decided to do one hour's f/w flying with an instructor before I left. That way I could get back in practice after an 8 month f/w layoff, and be legal to take passengers if I did 3 takeoffs and landings.

Well, I just went up with this real old guy who looked like he was born in an aeroplane. We did a bit of general handling; steep turns and the like. Then he asked me if I wanted to do a stall. Well, I'm scared of stalls, and I was tired after 52.6 hours of heli flying in 3 weeks, and I didn't feel like sending my stomach through the roof, but I said OK. He demonstrated first, and recovered just as it was about to stall, all very very gently. He told me to recover as soon as I could feel it. Well, I like it that way; my instructors always waited until the damn thing was falling out of the sky. I told him that and he shrugged, saying some people like to teach it that way, but he figures if you can recognise that it's about to stall, that's the time to recover. This makes sense to me. Flying is about recognising what's happening with the aircraft, all the little signs that things aren't as they should be, and getting better at doing that earlier and earlier. If we wait until it actually stalls, aren't we doing the exact opposite? Shouldn't students be learning to recover earlier rather than later, and practising recognising and doing just that? Aren't they learning NOT to be sensitive to what's happening with the aircraft, by leaving it so late?

Maybe I should post this in the instructors forum, but I'm interested in what everyone thinks.

[excrab]

Whirly - what an excellent post.

Certain flying schools seem to feel that unless the student has been scared whitless with max power full flap stalls the subject hasn't been covered properly, and then make things worse by doing hours of stall recovery prior to solo.

Surely a better idea would be to teach recovery with minimum height loss at first indication (either aerodynamic or stall warner) of the stall, and do the slightly more scary stuff - maybe even spinning - during revision for the skills test at the end of the course when the student is more familiar with the aircraft enviroment, less likely to be scared stupid and more likely to appreciate what is going on.

However, it would probably be unwise to suggest that developed stalls should be removed entirely from the syllabus.

[Genghis the Engineer]

Interesting point Whirly.

I'm afraid that personally I take my monthly practice stalls fairly deep, certainly to full back stick, although ideally before entering incipient spin (in an aircraft that does that). Then again, I spend much of my life test-flying, where significant caution is something that can only be a starting position - sooner or later I'm in the 60° bank, full power, flaps-down, rapid decleration case or whatever, which needs a certain amount of teeth-clenching at the best of times.

Whenever I fly with an SEP instructor, they usually do as you've just described - just to moderate buffet then recover - I think they're as scared of stalls as you are.

Flying with test pilots, microlight instructors or gliding instructors, they are usually happy to persevere into pitch break and wing-drop.

Which is more sensible, well I'm honestly not sure. It is realistic to recover at the first stall warning, and that's certainly what I do if I'm not deliberately aiming to stall. But, if student pilots aren't exposed to the deep stall, wing drop, and ideally incipient spin at some point, then they end up petrified of what in virtually any fixed wing aeroplane is a mildly entertaining non-event because they think it's something horrible and mysterious.

So what's the conclusion? Well, I think you should be comfortable taking an aircraft into the deep stall, and sufficiently aware to recover as soon as you nibble the buffet or the warner goes off in normal flying.

G

[fireflybob]

An interesting topic.

There is a distinction between a)the signs of an approaching stall and b)the symptoms of the full stall.

a) is characterised by, amongst others, reducing airspeed, control effectiveness, high nose attitude, stall warner and/or light buffet.

b)is charcterised by heavy buffet, nose pitching down, a/c descending and possible wing drop.

As far as instruction goes I see little value in teaching the student to hold the a/c in a stall. He/she should either be taught/briefed to recover at either the first symptom of the full stall or the first sign of an approaching stall.

[BayAreaLondoner]

I took a look at the FAA Practical Test Standards (http://av-info.faa.gov/data/practicalteststandard/faa-s-8081-14a.pdf) to get the language they use for stalls (note this is the new version that is coming out in August):

"Recognizes and recovers promptly after the stall occurs by simultaneously reducing the angle of attack, increasing power to maximum allowable, and leveling the wings to return to a straight-and-level flight attitude with a minimum loss of altitude appropriate for the airplane."

Interestingly, the older version prefaces the above paragraph with the following:

"Recognizes and announces the first aerodynamic indications
of the oncoming stall, i.e., buffeting or decay of control
effectiveness."

I interpret this as meaning that the FAA want checkride candidates to demonstrate full stalls and recover, rather than just announce the buffet and recover which, from what I have observed, seemed to be a bit of a grey area before.

Do others agree? I think it would be interesting to get a CFI's view on the language.

[john_tullamarine]

If I may add a little to the very pertinent observation made by Genghis ("It is realistic to recover at the first stall warning, and that's certainly what I do if I'm not deliberately aiming to stall").

One of the problems with stalling the Widget Mk 1 is that certification standards have changed over the years and the flight test approach adopted by the certification team may well have gone no further than what is minimally required to get a tick in the box, especially for a normal category machine not routinely used in training.

Thus, if the stall has only been tested to the onset, one could find in line practice that such a machine exhibits quite nasty characteristics if the stall is progressed beyond the initial stages. I can recall a tale from one very experienced trainer of test pilots who related how a popular high performance twin piston machine, when pushed a bit, would only too happily flick into an inverted spin ... the certification was not required, and did not, investigate the developed stall characteristics. The observation was made when a TP student thought it might be a good idea to push the particular (and otherwise very nice) aeroplane well into the stall .... apparently both pilots expressed a modicum of surprise at the time ...

Might I suggest for consideration that,

(a) unless the specific aircraft is intended for training manoeuvres in the stall regime, then a certain degree of caution is called for.

(b) if one wants to play vigorously in this area, then a utility or, preferably, acrobatic category aircraft is the way to go. At least the certification program had a look at the sorts of things to which an instructor might wish to expose his/her student.

What it really comes down to is ...why play test pilot without benefit of the checks and balances which the flight test fraternity employ to control their risk exposure to an acceptable level ?

[Genghis the Engineer]

Well said John.

I think this post points us towards a partial answer. When certifying an aeroplane, part of the task is to prepare advice for the POH showing what the characteristics are and what is the permissible handling envelope.

So perhaps although in normal practice, the aim should always be for a recovery at first signs of the stall warning, in learning to fly (or staying current on) any aeroplane type, there should be some experiencing of the limits of WHAT IS DESCRIBED IN THE OPERATORS MANUAL. This should, in most cases, accurately reflect what has been seen, and deemed acceptable, during the certification programme.

G

[Circuit Basher]

As I personally quite like practising recovery from unusual attitudes, I'll generally take practice stalls to their logical conclusion (and enjoy it!); this is when I'm solo or with someone who shares my point of view.

If I've got nervous passengers who are terrified of stalls and leap out of their seats if the stall warner so much as chirps when you hit a bit of lumpy air (I fly a Fuji which has very sensitive stall warner!), I take them almost to the point of buffet and recover (with their agreement and explaining what's happening). I tell them that they've just experienced a stall and so there's nothing to be nervous about. This generally calms them down from the dread fear that is promoted by the media of 'aircraft stalling' and the dire consequences.

[Wee Weasley Welshman]

I feel strongly that PPL students should be taught fully developed stall recoveries with wing drop.

Spinning was removed from the syllabus.

If you stall and instinctively apply aileron to correct wing drop you will spin. You have no training in spin recovery. You will die.

In addition the student should be able to demonstrate themselves adept at recognising and recovering from the incipient stall condition.

WWW

[foxmoth]

IMHO you should know (subject to the aircraft limitations) as far as possible, what the fully developed stall is like, and be able to recover from it in ANY aircraft you fly. The emphasis though should be on recognition and recovery at the incipient stage - preferably using aerodynamic signs not the stall warner.
The reason I prefer aerodynamic signs, is that the time you may be in an unintentional incipient stall you are probably concentrating on something else, this is when the stall warner goes unnoticed.

[essouira]

I agree with WWW. With my students I explore the fully-developed stall and demonstrate the effect of rudder on a dropped wing. They say it helps to understand the theory once they have seen it in the air. I build up to it gradually as students gain confidence so I certainly don't aim to frighten anyone. On consolidation practice we concentrate on recovery at first sign - which is what I advise them to do when practising solo. It may be interesting to copy this thread to the instructors' forum and see whether you get other views.

[Who has control?]

Interesting posts!

The one part of my PPL training that scared me most was incipient spins - I was convinced that the aircraft was going to flip over & plummet earthwards. But having practised a few and learnt to gently pick up the wing with just a touch of rudder, I felt more comfortable with them. We also did spinning, an exercise more feared in the anticipation than the execution, I think. it is definitely worth demonstrating the real world situation of recovering at the stall warning, but also going past the stall warner to a real, nose-dropping' stall.

I'm always a bit concerned that the standard recovery from an incipient spin, (by applying rudder), if done too enthusiatically is very close to the standard method of entering a spin.

[sennadog]

Interesting points being made here. From a novice's point of view I am of the opinion that it would probably be a good idea to push the stall a bit further. I have done the standard stall recovery in a Katana and after some trepidation "pushed" the stall a bit under the guidance of my instructor. However, I don't like the feeling very much and as soon as the stall is induced I immediately want to lower the nose and put power on. Having said that I think that the Katana is quite a benign aircraft.....

I have a bit of a phobia about stalling and spinning now to the extent that I don't like "chucking" the aircraft about too much (not too keen on steep turns etc) and this comes from a lack of confidence, more than anything! What I would like to see is more investigation of the stall (in the correct aircraft!) and spinning as part of the PPL - if for no other reason than to build confidence and enable students to get out of trouble if it ever occurrs!

My first port of call after gaining a PPL would be to the nearest Aerobatic Instructor to get the confidence and the knowledge of how to sort things out if they get pear shaped.

In short, develop the stall further as part of the PPL training to give students a better chance of recovering from severe situations and bring back spin training.:)

[pulse1]

I am pleased that this subject is being discussed because I have flown with too many instructors, including an examiner, who did not make it clear when they wanted me to recover. Now I always ask but generally prefer a full stall because I also believe that it is important to practice recovery from a nose down attitude which most of us boring cruise only PPL's rarely experience and, one imagines, could be a bit panic inducing for some.

[foxmoth]

Who has Control-
I think you will find current practise is NOT to pick up the wing with rudder, just use it to PREVENT further wing drop, then roll the wings level with aileron AFTER recovering from the stall.

[Collater]

I find this a very interesting post.

During training at a large, and in my view very professional, school my excellent but dogmatic instructor insisted on recovery from fully developed stalls in a PA-38. They scared me ****less with the invariable random wingdrop and my inclination to recover with aileron. I eventually got the hang of it, avoided spins - just - but never grew to love the process.

On my GFT the examiner - also from the school but with whom I had never flown before - demanded recovery from the incipient stall, which I had never done! Can you believe that I cocked it up by letting the stall progress to fully developed, much to his annoyance? I then had to let him see that I really could recover just from the buffet etc.

Then having passed (Feb this year) I went to my local - very professional also - flying club to get checked out on the PA-28. The instructor put me through what seemed like another GFT and also required recovery from the developed stall, albeit that in the PA-28 it at least goes down level.

Personally, I suppose that I am glad that I had the experience but I never intend getting near the stall and at the first sign will be getting the nose down and banging on the power. And as for spinning..........

[paulo]

Just one thing whirly... you happily fly R22's I assume, and yet can find something, anything, to be scared of in f/w? Weirdo. :D :D :D

[Rod1]

Firstly, I think I need to make it clear that I am not an instructor, so there are lots of people posting on this who will know much more about this than me.

I came into power from Gliding. In order to go solo I had to do a lot of stalls, plus recovery from full and incipient spins. I have since done a reasonable amount of aerobatics.

I have two main questions. The people who find Stalls frightening, do you practice them regularly?

Have you considered doing some gentle aerobatics, in, say, a Pup 100 or similar?

If you do try the aerobatics, I think you will find your stall problem will vanish, and you may find that you have more fun, without the worry in the back of your mind.
:D

[Chuck Ellsworth]

I wonder if maybe you are exaggerating just a little in your statement WWW.

" If you stall and instinctively apply aeliron to correct wing drop you will spin. You have no training in spin recovery. You will die. "

In that , that is not necessarily true in all airplanes, isn't that sort of fear mongering?

Cat Driver:
...........................
:D The hardest thing about flying is knowing when to say no.:D

[Genghis the Engineer]

I think Chuck has a fair point, although we should always aim to do it by the book, the truth is that MOST small fixed wing aeroplanes will recover from most spin modes if you take the following actions:

- Close the throttle
- Scream "aarrggghhh"
- Let go of the controls.

G

[Keef]

I'm confused (not unusual).

I thought the "correct" process was to keep the aircraft in balance (ball in the middle) and pick up a dropped wing with aileron. Works with "modern" aircraft - some of the very old types might be different. Won't "picking up a dropped wing" with rudder hasten the onset of a spin?

If it's stalled, unstalling first might be a good idea.

But, to return to the point: I've flown with US instructors who go almost berserk if I do a "fully developed" stall. They seemed to want me to recover at the first aerodynamic indication of an impending stall.

[Tinstaafl]

My training & experience is that it's wrong to try to 'pick up the wing' with rudder for a stall recovery.

The intent should be to stop yaw ie control the heading, not "raise the wing".

If HDG can't be controlled then a spin recovery technique is more appropriate.

As for being frightened by the process, then maybe the student was introduced to it too severely? My approach is to start with the most benign stall I can set up then, as my student's confidence increases, I progress to more 'interesting' varients.

The key is to progress at the student's comfort rate, not your own. If that takes more than one flight then that's OK. As instructors we all have some mental idea of what we think 'should' be a normal rate of progress. This fails to appreciate that every student is different.

[alphaalpha]

My own experience is:

I was taught at PPL training to recover from fully developed stalls entered 1. no power & clean, 2. some power & flap. Also recovery from incipient spin. Isn't this normal? I remember being fairly comfortable with this, being introduced progressively, although the first wing-drop was quite unnerving. I think I did this training at about 6-9 hours total time - definitely before first solo.

For US/Australian BFR renewal, stalls included the 'departure stall' (full power, no flap) and the 'landing configuration stall' (some power, full flap/gear and 30 degrees of bank). In all cases the instructor wanted to see recovery at first sign of stall: buffet or stall-warner.

For ir training, the unusual attitude recoveries included approach to the stall: clean, in landing configuration (as per BFR above) and accelerated stall. In all cases recover at first sign of the stall.

All the above seems sensible to me -- i.e experience full stalls, so you know what it feels like and you can recover if needed, but concentrate on recognising the approach to the stall and recovering before it happens.

I also did a little bit on recognising and recovering from a spin during imc training (carried out in vmc, of course), but I don't think this was part of the syllabus.

Should we go out and practice full stalls & recoveries as part of our own program of maintaining currency? I have never done so.

Regards

[White_Arc]

I personally feel that a student should atleast have one fully developed stall, this is so that if they do not recover quick enough while by them selves because of real distractions, they will not freak out, they will atleast know what it feels like, what it looks like, and what to do if a passenger grabs the control yoke because they are freaking out....In the US, you only have to do the real thing when you are on your CFI course, but i always say to students, just try one out, it might take that scary edge away and you never know you may like it......

Now to getting out of one, you first have to stop the spin,by pressing opposite rudder this stops the rotation but not the stall, if you try to use your Ailerons they will not work fast enough as you have air seperation above the wings you would probably hit the ground first before anything would happen, this is what causes the stall in the first place. Once you have stopped the spin you have to then break the stall...Until then you are still in the stall and can quite easily enter another one if you do not break the first stall...
Trying to stop a fully developed stall with use of ailerons can be very dangerous, you could tighten the spin and gain airspeed..Not good.. Think of the G forces on the plane and your VA speed......Thats why Normal and Utility aircraft are designed to stall first, so that you are not able to go over the VA speed with high G's and lose your wings....:(

Happy Flying

White Arc

[englishal]

To slightly re-phrase....If you try to use aileron to pick up a wing which is dropping, what you do is end up increasing that wings angle of attack to beyond the stall, and reducing the other wings AoA to below a stalled condition. This will lead to wing drop and possibly a spin. Even if you are not yet stalled, but close to stalling speed, vigorous use of the ailerons can put you into a spin by increasing one wings AoA to beyond the critical angle. I don't think you need worry about your wings falling off in a spin, for the reason that while in a PROPER spin, the wings are stalled and the aerodynamic loading is fairly small. In a spiral dive however, this could prove to be an inconvienience.

Last dual check I did the instructor made me stall the aircraft and hold it stalled for around 20 seconds, controlling it using the rudder. This was excellent training, as it makes you really appreciate what is going on and how to control the aircraft....

By the way Whirly, is stalling a FW really as scary as auto rotation in a helo???

Cheers
EA

[FlyingForFun]

I've waited a while before responding to this, to see what others - especially instructors - had to say, and I'm pleased that many people agree with my own thoughts.

I believe that insipient stalls and fully developed stalls are both equally important.

In the normal course of things, if you accidentally put your aircraft close to a stall, it's important to recognise this as early as possible, and recover promptly - hence the importance of the incipient recovery in training.

However, if the proverbial crap does hit the fan, as foxmoth says, you're quite likely to be distracted, and a fully developed stall is not inconceivable. You must be able to control and recover from this.

Knowing instinctively what to do is vital. As www said, try to raise a wing with aileron, and you're dead. (Keef - this is true of every aircraft in a fully developed stall. All modern aircraft are designed so that the outer part of the wing - where the aileron is located - will stall last, thus ensuring that you have a small amount of aileron control before the stall has developed fully, but I would question anyone who recommends that you deliberately take advantage of this safety feature.)

It's also important to actually do the recovery and see what control pressures are required. As "Who has control?" says, if you apply too much rudder, you could well start a spin in the opposite direction. The solution is to practice enough that you know how much rudder pressure is required.

An interesting thing which I learnt during my aerobatic training: if you apply full opposite rudder, and also apply full forward stick before the yaw has been brought under control, the plane is now set up perfectly for an inverted spin. When my instructor tried to get me to do this deliberately, I found it very hard - my instincts told me that it wasn't the right time to push the stick forward. This is a testament to how well the training works - but I can certainly imagine someone who has read the theory but not seen it in practice may panick when faced with a stall and wing-drop, and apply exactly this combination of controls.

And finally - a personal experience which demonstrates how theoretical knowledge is not enough. Fresh out of my 10-hour aerobatic course, I booked one hour of dual in a Pitts S2C. Shortly into the flight, the instructor suggested I try a loop. I hadn't quite got used to the super sensitivity of the controls, and used too much back-pressure. The plane stalled at the top of the loop. I immediately recognised what was happening as a stall. I also knew that I was inverted - hence it must be an inverted stall, so applied the correct controls to recover from an inverted stall - back stick. This, of course, is totally wrong - a stall is only inverted in negative G flight. A loop is a positive G move, so the stall was actually an upright stall, even though the aircraft was in an inverted attitude, and I should have applied forward stick to recover. Of course I knew this on a theorertical level - but applying it in practice, in an unfamiliar situation, is a completely different story. Fortunately, on that occassion, I had a very experienced aerobatic instructor sat in the front seat.

If there's a chance that your aircraft can get into a bad situation, you should know how to avoid that situation, and know how to recover if necessary.

John_tullamarine, I didn't realise that some aircraft don't have their stall investigated during test flying, I'll certainly be checking the POH on new aircraft in future! I love PPRuNe - it's a constant reminder that there's so much more to learn.

Fly safe,

FFF
--------------

[Wee Weasley Welshman]

Chuck:

" If you stall and instinctively apply aeliron to correct wing drop you will spin. You have no training in spin recovery. You will die. "

No thats not scare mongering. Thats boiling down the essential facts to their simplest format.

There are people from a broad spectrum of experience here. Now you and I both know that there are lots of common types out there (C152, PA28 etc.) that will resist adverse yaw spin entry and which recover from a spin almost automatically.

But there are plenty of types that don't.

I have completed adverse yaw initiated spins entries in C152, C172, PA28, PA38, Bulldog, Vigilant and F22. I have sat in the back and watched it being taught on a SeneccaIII as well. These types alone showed how some aircraft only just do it if you try your hardest whilst some aircraft go incipient at the slightest twitch of the aileron.

I don't think the average Bloggs has much chance recovering from a fully developed spin if he has never ever seen one before.

Sometimes a little bit of scare mongering is good for a student. But only a little.

Cheers,

WWW

[Who has control?]

Foxmoth - I take your point. Use the rudder gently to prevent to aircraft from yawing further towards the dropped wing, unstall it and roll level with ailerons. Right?

Sennadog - I know how you feel..

I was being checked out in a new aircraft a few weeks back and the low speed characteristic were demonstrated thus:- close the throttle, drop the flaps fully and pull the stick right back.

We ended up decending nose high, wings level, slats out and with the stall warner peeping. A Cessna would have dropped a wing and rolled over rapidly earthbound. In the other aircraft, the ailerons and elevators were still effective and it felt very comfortable, sitting upright.

[englishal]

I must mis-understand WWW.....surely you weren't practicing spins in the Seneca (or whoever you were observing?)..?

Cheers
EA

[Genghis the Engineer]

Correct me if I'm wrong, since it's 10 years since I wrote the certification reports, but I'm pretty sure that the Vigilant isn't cleared for deliberate spinning either?

G

[Wee Weasley Welshman]

You can teach incipient spin entry/recovery in a Vig and a Senecca though.

WWW

[Wee Weasley Welshman]

In fact the Grob109 is great for it as you have all that adverse yaw available - Bloggs gets the idea straight away.

WWW

[Chuck Ellsworth]

O.K. Everyone how do you recover from an aerodynamic full rudder lock?

Whirleys simple question seems to have brought out many different scenarios among the knowledgeable among us, sooooo lets see who knows how to get out of a full aerodynamic rudder lock.

P.S.

John _ T... you probably know, but lets see if the regulars here can explain how such a condition can occur and how you get out of it...

I just love puzzles, especially when pilots get playing around with them. Gives them something to do when they lose their crayons and colouring books. :D :D :D

I will leave all you to toss this one around for a few days and I am asking my good friend WWW to referee for me.

For christ sakes don't anyone go out there and try and get your airplane to do this, till you know how to recover from the condition. :):)

...................
:D The hardest thing about flying is knowing when to say no.:D

[paulo]

Entry: Tailslide into it at the top of an up line? :D

[FNG]

Doing aeros in a Pup 100 might be a recipe for getting scared! Nice for stalls and spins though. Fully developed stall just a noddy dog effect and worth doing if you're timid about stalling.

I would vote for teaching full stalls (and, indeed, spins) during training. This is, I suppose, ye age olde debate. I can see an argument that, for the purposes of tests or checkouts, it might be sufficient to demonstrate the ability to (a) notice and (b) recover from an approaching stall, especially in the landing configuration, but, against this, shouldn't someone proposing to fly solo be able to show that he/she can deal with an emergency which can happen to every aeroplane? Drivers ought perhaps to be taught how to get cars out of skids, but the consequences of skidding a car are less commonly fatal than the consequences of stalling and spinning an aeroplane. We are taught how to react when the the engine stops turning. Shouldn't we also be taught how to react when wing stops flying?

[paulo]

My low hours tuppence worth.

Early on in my PPL, solo, I got into an inadvertant spiral dive. Instinctive reactions sorted it out, but if I'd used those same instinctive reactions in a spin, me and a Warrior would probably be at the bottom of a lake in Florida now.

Since I left my PA-28 days behind, I've done alot of spin recoveries - didn't like them at first, but you get used to it, and am very glad I've done even if I packed in aeros tomorrow.

I once heard an analogy for not teaching spins, roughly - "it's like not teaching your kids how to cross a big road, on the basis that you've told them they shouldn't play outside the block".

There's three ways it can go:

(a) You never have a spin.
(b) Your first spin is with an instructor.
(c) Your first spin is without an instructor.

Dunno about you, but (c) would scare the crap out of me.

Anyway, you're an R22 pilot, so this should be a walk in the park. ;)

[Whirlybird]

paulo,

I know it sounds weird that I fly helicopters but I'm scared of f/w stalls. I've always felt more comfortable with helicopter flying. I think it has a lot to do with the standard of instruction I had for my PPL(A), because I wasn't scared when I started. In fact, I remember saying that stalls were fun. I think that annoyed my instructor, and maybe he deliberately set out to scare me; I wouldn't be surprised, from what I remember of him. But I'm damned if I can actually remember what happened, if anything did.

Englishal,

Autorotations are not really frightening if taught properly, any more than stalls are. But maybe a better rotary parallel is vortex ring (settling with power, for those across the pond). Without going into great detail, it feels like a f/w stall - you get buffeting and shaking, then the helicopter starts to fall out of the sky. You recover by pushing the cyclic forward to get some forward airspeed. My first instructor got me to recover at the first signs; the next one wanted us to be actually dropping out of the sky. By then I didn't scare easily, but I'm really not sure I saw the point of leaving it as long as he did.

When I have time I ought to find a good f/w instructor and practice some of this stuff properly. But the various opinions here are very interesting.

[Ivchenko]

Great thread

Some of the later posters have pointed out that recoveries from full stalls should be taught and practiced, because it is possible (say, finals, unfamiliar airfield, turbulent day, lots of traffic, uncomfortable passenger, a/c yet to clear the runaway etc.) to miss the signs of an incipient stall and find yourself all the way there with a wing dropping at 2 or 300'

Definitely agree - happened to me once showing off and generally being a prat in a Yak; glad I was able to hold the dropping wing, apply power, ease the nose down and land off the approach without too much drama but it taught me a lesson.

So if the type permits, teach 'em all the way, preferably with flaps, bank and full power. These things are a lot less frightening once you've been there with an instructor.

[Tinstaafl]

A 'rudder lock'?

I can only vaguely remember hearing the term. Damned if I can remember what it is!

It sounds like an aerodynamic effect caused by too much sideslip? Is it related to a fin stall?

I'll take a punt at an answer. I imagine that the solution would be to change IAS - probably a reduction - to reduce the magnitude of the aerodynamic forces, or to roll to induce a sideslip to change the airflow pattern.

[BEagle]

First the student should be shown the warnings of an impending stall - speed low and decreasing, controls less effective, attitude becoming relatively nose high in level flight and then the onset of light buffet.

Then the student should be shown what happens if the warnings are ignored and a full stall develops - identified by increasing buffet, increasing rate of descent, possible wing drop and nose drop. But they should only see all the indications once as it must be made clear to them that henceforth they will recover either at the stall warning stage ('incipient') or the first identification of a fully developed stall.

The recovery is STANDARD:

FULL POWER and simultaneously move the control column centrally forward until an attitude is reached at which the identification ceases - then maintain that attitude.

Once the ac is unstalled, level the wings and recover from the descent - the rudder should only ever be used to keep the ball in the middle and NEVER to 'pick up a wing' or other such thing!

Only when the clean, fully developed stall and standard stall recovery with minimum loss of height has been mastered by the student should other areas of stalling be taught.

[Who has control?]

Its interesting that most of us low-hours PPL & students too have probably only ever been taught stall recovery from a wings-level attitude at altitude. I personally thought 'this is silly, I'm never going let myself get into this situation - no power, nose pointing towards heaven, stall warner shouting at me - no way!' So the Pavlovian reaction to stall recovery is 'stick & throttle forward!'

But Ivchenko has raised the spectre of something a little more ominous - a heavy aeroplane, bit low on base, bit slow too, bit late turning finals so using a bit more bank angle. Do I detect a recipe for disaster? And thats a scenario that we are not taught how to get out of.

[FNG]

Did you not also do a recovery in a descending turn with flaps lowered? I was both taught this and tested on it. Whirly: why not get an aerobatic instructor to show you departures and recoveries in various wacky attitudes? Good for confidence generally. Less scary and more fun than many fairground rides.

[Julian]

I was taught to recover at the buffet, from what Iunderstand spining had just been taken out of the sylabus. I agree with Whirly in that you should be taught to recover at the first signs not after a full blown stall...

However...

I also agree with WWW (see it does happen mate!!!), in that everyone should also know how to get out of a spin and its a shame its no lnger required. I did a couple with the examiner on my GFT as he wanted me to experience them even though it wasnt part of the test.

When I have some spare time I intend doing the AOPA aerobatics course for some fun and hopefully some valuable experience!!!

Julian.

[FlyingForFun]

Rudder lock, huh? Never heard of it!

A quick search of the web didn't reveal too much, except this document from NASA (http://www.dfrc.nasa.gov/trc/ftintro/pdf/steady.pdf) which doesn't give too much detail. I'd be very interested to hear...

FFF
-------------

[Whirlybird]

BEagle,

What you say makes a lot of sense. Show the student a fully developed stall and teach them to recover from it ONCE, then emphasise recovery from the incipient stall (see, I'm even remembering the right terminology again :D ). I seem to remember whole HOURS of falling out of the sky, and feeling sick at the end of it. I think that's how I got scared of something I found fun in the first place. A young male instructor who couldn't stand the fact that a woman twice his age wasn't even remotely nervous, I suspect, though I can't quite remember. Well, if that was the case he achieved his aim! And he's probably responsible for my becoming a helicopter pilot, at least to some extent.

The trouble with my doing anything remotely aerobatic is that I do get airsick quite easily. I went for a gliding trial lesson and got persuaded to do a loop; I did it too, and it was fun, but then I felt ill and the instrutor had to do the landing. But I think my next f/w biannual check ride is gonna have to be stalls and spin recovery, all the same. Any volunteers to teach a wimpish, rusty f/w pilot, who throws R22s around and extremely happily auto-rotated off a 8000 ft mountain in the US (with an instructor), but dreads the very idea of a spin in a plank-wing? :eek: :D

[englishal]

You're a braver person than me WB ! I had a close look at the tail rotor of an R22 once....seeing the 10mm nuts holding it on was enough to make me quiver ;)

Cheers
EA

[bookworm]

The Airborne Express DC8 accident (http://aviation-safety.net/database/1996/961222-0.htm) in 1996 illustrates some of the perils of exploring the stall envelope mentioned by john_tullamarine.

This crew, on an evaulation flight after major mods, deliberately stalled their aircraft and were unable to recover. IIRC, it transpired that neither of the crew (one of whom was a chief pilot or training captain) had actually stalled a DC-8 before, and the simulator they used was unrealistic in the stall regime.

[Chuck Ellsworth]

F.F.F.:

I can assure you that a rudder full over, ( full deflection lock ) can occur on some aircraft.

Hint.... find the RAF ferry pilot airplane check book that was used for referenceing how to fly all aircraft that ferry command flew during WW11.

You will find the warning of how to avoid a rudder lock in that book, also the recovery technique. One word of caution the recovery technique as described in the book is only partially correct. There are two methods for recovery, the guys during WW11 just didn't get around to exploring the full envelope of that unusual problem.

I can assure you that rudder lock is possible, I personally have experienced same during in depth evaluations of the flight envelope for air show display purposes. ( At safe altitude. ) One of my friends lost control of his airplane at low altitude due to a double engine failure, ( out of fuel, climb attitude low airspeed low altitude. ) most likely senario was due to fatigue and fear forgot to close throttles before selecting fuel boost pumps on and one engine went to full power during the next few moments of their time on earth it is most likely that the rudder locked ( Based on very reliable eye witnesses descriptions of the airplane attitudes prior to impact with the ground. ) and it was unrecoverable due to low altitude, the airplane impacted in a vertical attitude rotating to the left , very little material left due to impact explosion.

One year prior to this accident I had very carefully briefed the pilot of this airplane on how to recover from an inadvertant rudder lock. He was profficient in the manouver, I know this because he had gone out and induced a full rudder lock and recovered. His co-pilot confirmed this and there is no doubt that they had experienced the condition by the very graphic description of the violent airframe shudder they experienced. However it was impossible to recover from the possible inadvertant rudder lock he encountered the day they died because the very low altitude he was at when he lost control.

And by the way...I am not fear mongering only describing factual and preventable loss of control situations that can be encountered in some airplanes.


NEVER:

Attempt to explore any envelope of flight in "ANY" aircraft beyond what is described in the Pilot Operating Handbook.

Cat Driver:

.....................
:D The hardest thing about flying is knowing when to say no.:D

[Final 3 Greens]

Whirly

Have flown a bit in the States and undergone training and BFRs, in my experience it is a frequently held view amongst US instructors that stall recovery should be made at the buffet (or stall warner), by unloading back pressure and increasing power to fly away with the minimum loss of altitude.

This is because their focus is on recovering from stalls at low altitude where recovery with any significant loss of altitude might cause impact with terra firma.

I hope this helps to explain your experience.

Before anyone jumps on me for this post, I am neither agreeing nor disagreeing with the view, merely promulgating my experience!

Finals :)

[paulo]

Chuck - at the risk of straying way off whirly's topic - Could you explain the rudder lock phenomenom? I'm trying to visualise it based on that NASA document, but struggling. I doubt I'll be flying anything capable of it, but I do find the whole performance envelope & handling stuff quite interesting.

[Chuck Ellsworth]

Sure Paulo:

The rudder lock problem can occur on several models of the PBY Catalina, namely some PBY5A's and the Super Cat conversion of the PBY.

I flew the PBY for about seven years before I accidently discovered that the rudder will lock full on if you cross the controls at the wrong airspeed and angle of attack.

Briefly I was practicing a manouver for airshow demo purposes ( at a safe high altitude thank christ. ) and at the top of a normal wingover I crossed the controls, the turn was to the right with full right aeliron and I applied full left rudder.

There was a horrific fu...ng bang as the rudder hit the full stop limits and I couldnt move the rudder so I asked the co-pilot to push on the right rudder, we could not move it so I quickly pulled the evevator to full up and induced a stall, the rudder immediately responded and I had regained control.

At that time I was flying for a large waterbomber company and was the training pilot, after discussing what had happened I found out that this was in fact a known problem with some versions of the PBY, the military had noted in their training manual that under certain circumstances, they only listed side slipping, the rudder can aerodynamically lock.

Their recovery method was to close the throttles and increase airspeed to 120 knots, at that point the rudder will unlock.

I prefer my method , mainly because it worked and I have no great desire to practice the manouver again due to the very severe airframe buffet, not to mention I am not to happy with ten or twenty tons of airplane in an uncontrolled flight realm.

The cause is the design of the rudder on some models, they have different balance methods. Some use mass balance and others use a combination of mass and aerodynamic balance, the latter will lock under some flight conditions.

However you must really use an unusual control imput to induce the locked condition.

Maybe someone from N.Z. could add to this as I understand they encountered the probllem several years ago during re-current training with their PBY the former C-FJCV.

I would be interested in knowing about their experience.

Cat Driver:

.......................
:D The hardest thing about flying is knowing when to say no.:D

[LowNSlow]

I think stall should be taught progressively building up to full flap, full power departures as mentioned by previous posters. One stall that isn't often taught is the "turning through finals" stall which scares the crap out of me so I practice it at a decent height!

I also feel strongly that stall should be practiced on a regular basis. If the pax agree, why not chop the power and do a quick stall enroute? Does it REALLY matter if you lose a minute or two on your journey?

englishal have you looked at the 5/8" (15mm) bolts holding the wings of your aeroplane on :D :D

Whirl, if you want to do some stalls in an Auster drop me a line. It's stall is quite docile, honest :D :D

[Who has control?]

Straying a bit off thread I'm afraid, but it sounds as though Rudder Lock is the phenomenon that caused the loss of early Handley Page Halifaxes, (4 engined - twin tail bomber), in WW2.

The tail fins were originally rectangular with the top and bottom leading corners chopped off at an angle.

After many aircraft were lost in inexplicable accidents, the characteristics were investigated and after a crash that killed the test pilots, the tail fins were changed to a rectangular shape.

[englishal]

Hmm, good point LNS :D