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flyboy1971 4th Aug 2012 13:51

Stalling - Help & Advice
 
Hi,

I really could use some advice regarding Stalling and the fear of! I've stalled the plane (C152 Aerobat) in the past, no problem, apart from one ocassion where a control input put the plane into a spin. Since then, I just cannot get my head around it - i've built up an inexplicable fear of the stall and the associated unusual attitude that this is now becoming a blocker to my doing my test.

Any advice/help/words of wisdom. I need to get this done!

Aspiring Pilot Alex 4th Aug 2012 13:57

I was in the same situation as yourself when I did my stall recovery training. What helped me was that my instructor offered to give me a lesson dedicated to spinning. When I was comfortable recovering from spins, stalls were a piece of cake. It's a shame spinning isn't in the syllabus as I found it really helpful.

Best of luck!

Alex

foxmoth 4th Aug 2012 13:59

Given your location I would suggest a trip to Kemble and do the stall/spin course at UH, this will definitely teach you that both are nothing to be frightened of if you know what to do, will teach you how to recover from and avoid both and ensure that you can stall without getting into a spin.
Edited to say that seeing you are still doing your licence, try and do this with your instructor, much of the posts below give reasonable guidance. As Ghengis says lower down, doubt if it is actually a spin being a Cessna, but if you do a spin lesson learning both that and spiral dive, see the difference and how to recover from both you should get over your fears.

taxistaxing 4th Aug 2012 14:01

I was struggling with it on revalidation my ppl recently. What helped me was when I was shown how gentle the recovery is in a 152. No need to shove the column forward just ease it to neutral and full power. That way you only lose 200 feet or so and it feels quite gentle. Get the instructor to show you a few. And don't go near the rudder when recovering!

The500man 4th Aug 2012 14:12


And don't go near the rudder when recovering!
Well that's an interesting piece of advice!

Pilot DAR 4th Aug 2012 14:15

Practice some extreme slow flight, with the stall horn just screaming, and lots of power on. Just keep the plane balanced there. You will get the feel of the pitch forces very near the stall, and the required precision of control in roll and yaw. If it breaks in the stall while doing this, pull off the power, and recover normally. As you practice this you will realize that you can enter or recover that stall at will.

The 152's stall warning horn is particularly good for this, as it will produce an intensifying sound with the deeping approach to the stall.

As for the recovery with lots of altitude, what's the worst that can happen? You're pointed down, recovering form a dive - that's okay.....

Cows getting bigger 4th Aug 2012 14:36

The stall is nothing to be afraid of, especially in a simple aircraft such as a 152.

Lots of good advice here, some not-so-good. As pilotDAR says, with an instructor, try a bit of slow flight at a reasonable altitude. Get the feel of the aircraft and recognize the various signs and symptoms. Notably, reduced responsiveness of the controls, yaw and buffet. Try and fly on the 'edge ' of the stall warner and then make some control inputs noting how the stall warner reacts. Finally, do a clean stall and recovery with no power. To start with, you can do this with no control input during recovery other than elevator. Say to yourself "centrally forward" and force yourself not to use aileron. Note how you only need to pitch down to an attitude where the horizon is about half way up the windscreen; there is no need for frantic inputs and death defying dives. Get comfortable with this, lots. If a wing drops during the process, don't worry, just concentrate on getting the right attitude ("centrally forward") and, once the aircraft has gained flying 'speed' then you can sort out any wing drop that may have developed.

Once you are comfortable with this, you should progress on to making the stall recovery more efficient. This is done by introducing power at the appropriate point and, for finesse, using rudder to arrest any wing drop that is developing. However, never forget that the only way you are going to get out of a stall is to get the wings working again. This is done by ensuring they are both at angle angle of attack where they provide lift, ie from your bum up through your head -"centrally forward".

Finally, you are not alone, there are many pilots and instructors who are unnecessarily afraid of the slow speed regime. Yes, treat it with respect but that is all. It is only when you progress on to far more fanciful aircraft that the stall can lead to some interesting things.

taxistaxing 4th Aug 2012 14:40

Yep I was told leave the rudder alone as this can initiate a spin. Equally if a wing drops, nose down and then roll the wings level with the aileron.

Genghis the Engineer 4th Aug 2012 15:01

Ah, one of my mastermind specialist subjects!


The stall occurs when one of two things happens - either flow separation on one or more of the wings, or the stick is fully back and the aeroplane held on the back of the drag curve. Either way, the aeroplane isn't fully controllable, and is losing a lot of height - neither of which are happy conditions.

One or more of the following may mark the stall:

- Wing rocking
- Wing drop
- Nose-down pitching motion
- Aeroplane held nose-up, usually with the yoke fully back.
- Very high rate of descent (this is pretty much universal)

In any aeroplane you are likely to ever get your hands on, the solution to all of these is absolutely the same.

(1) Move the stick forwards.

Don't do it sharply, don't go a long way, basically relax any back pressure, and bring the stick roughly to the middle.

That's it, the aeroplane is now flying again and under control. Technically, no other action is needed.


There is a second issue however, which is the loss of height, and if you manage to stall at low level, you particularly want to reduce that. Hence the second thing you ideally want to do

(2) Apply full throttle (and if you had it on, shove the carb heat knob back in).


Done reasonably promptly these will between them unstall the aeroplane, and minimise height loss. Then it's just a case of bringing the aeroplane back to a shallow climb, or level flight attitude (if in doubt, go for the climb) and once the aeroplane is level or climbing, bring power an pitch back to a normal flying condition.

There are four big things that you can do wrong.

(1) Not move the stick forward straight away
(2) Increase power before you move the stick forward, or fail to use full power.
(3) Try to pick up any wing drop BEFORE the wing is unstalled.
(4) Fail to keep the ball in the middle (do this with the rudder, and you don't actually need to look at the ball - you should be able to feel if it's out of balance by a sense of sideways movement).

That is basically it for ensuring your safety; after that, any other subtleties are subtleties about elegant flying and impressing instructors. But on those subtleties:-

- Don't push the stick forward to far or too fast, or you'll bunt and/or lose too much height still.
- Don't wait for recovery, do it as soon as you see or hear symptoms of the stall.
- Don't expect all aeroplanes,all the time, to pitch nose-down (especially at forwards CG conditions)
- If you had flaps on, raise them only in stages, at a good speed and safe height and whilst climbing.
- Remember that wing drop won't do you any harm, just take care not to try and raise the wing until the aeroplane is fully unstalled.


The stall is not dangerous, and the spin entirely avoidable. The ONLY thing likely to kill you is stalling very low (that is, below 500ft), and failing to take proper actions. In other words, it's only the height loss that is a problem.

I've spun C152 - and you have to try very hard to get one into it - I *suspect* that all you saw was a bit of wind drop, and perhaps what might have eventually become a spin if uncorrected (called the "incipient spin"). There are aeroplanes where this is something you need to be a little careful of, but not a C152.

G

The500man 4th Aug 2012 15:02

taxistaxing, fair enough. I think what you are describing though is more of an unusual attitude recovery, which although includes stalls is not entirely relevant to the OP.

In the context of this thread I would say that a "recovery" is going to include a full power climb back to entry altitude, which will require a significant rudder input.

Flying in balance in the first place will most likely prevent wing drop and that too will require use of the rudder.


However, never forget that the only way you are going to get out of a stall is to get the wings working again. This is done by ensuring they are both at angle angle of attack where they provide lift
Also never forget that lift is still produced above the stall AoA!

EDIT: I just complained about nit picking in another thread and now I've just done it myself! Sorry, I know what you meant. :ok:

taxistaxing 4th Aug 2012 15:24

Ok. Would you say rudder only once the stall has been recovered? I.e. nose forward, power on, roll wings level and neutralise yaw once recovered and climb established? I was told no rudder initially and that nose down is the first reaction, although in practise the whole recovery sequence is obviously very quick.This was in the context of a ppl reval in a c152.
Apologies for hijack of the thread but seems relevant to the discussion!
Ta.

Genghis the Engineer 4th Aug 2012 15:38

Rudder throughout, but ONLY to keep the aeroplane in balance (in other words no discernable sideforce and the ball in the middle), NOT to pick up a dropped wing.

G

The500man 4th Aug 2012 15:43


Would you say rudder only once the stall has been recovered? I.e. nose forward, power on, roll wings level and neutralise yaw once recovered and climb established?
If you think about it as soon as you apply a power change or a pitch change that effects airspeed you will need a rudder input. Personally I don't have a problem with using rudder to arrest a wing drop, but there is a fine line between that and picking a wing up, which you will see on Genghis' things you can do wrong list.

The idea of forward stick/ yoke and then rolling level is that you can't stall at 0g, and you can't bust your rolling g limit, but you can use full aileron to roll level as quickly as you can.

It's fine to say you won't use rudder when you are stalled, but for the sake of a PPL skills test, I don't think an examiner would want to see you delay adding full power, because that is part of the "standard" stall recovery. As soon as you add power you will need a rudder input.

taxistaxing 4th Aug 2012 15:52

Thanks for clarifying chaps. OP, apologies for the misinformation.

DB6 4th Aug 2012 15:55

One thing and one thing only causes an aircraft/aerofoil to stall: increasing the angle of attack beyond the critical.
Recovery is effected by reducing the angle of attack below the critical.
This is normally done using the elevators.
Adding power as you move the elevators down will help the wing unstall more quickly.
Once the aerofoil (wing) is unstalled you can use the flight controls normally - rolling wings level and raising the nose at this point will prevent further height loss.

Not much else is important.

n5296s 4th Aug 2012 16:17

One other thing to help you gain confidence: you should find an instructor who's happy to demonstrate and then let you fly what's sometimes called a "falling leaf" stall (and sometimes isn't). Whatever it's called, the goal is to HOLD the aircraft fully stalled (yoke/stick fully back) for an extended time, GENTLY using the rudder to keep wings level. You can fly like this for as long as your altitude will let you - the descent rate is high (of course) but you are still flying. When you've had enough, yoke forward and fly out of it. The plane will bob up and down as the wings "try" to unstall themselves.

And definitely +1 for doing some basic spin training.

Pittsextra 4th Aug 2012 16:23

go to Alan Cassidy and he'll sort you out. I'll refund you if not.

mad_jock 4th Aug 2012 18:46


you should find an instructor who's happy to demonstrate and then let you fly what's sometimes called a "falling leaf" stall (and sometimes isn't).
That has been deemed bad practise and a training com has been put out to stop that crap.

FullWings 4th Aug 2012 19:11

Lots of sensible suggestions.

Maybe a pre-aerobatic session with one of the many excellent qualified pilots we have in the UK? Once you've got used to recovering an aircraft from any attitude/airspeed, stalling won't seem a problem any more!

If you've developed a distaste or "fear" of stalling after a wing drop, it's possible that you're more sensitive to low or negative 'g' than the average pilot - it might be worth mentioning that to your instructor(s) and see what they say...

piperboy84 4th Aug 2012 19:17

3. Questions,

1.
Is a "falling leaf" really a stalled condition, and if not what signifies advancing from a falling leaf stall to a full stall condition? and will a falling leaf always progress to a fully developed stall or will you just basically flutter all the way down if inputs are not changed.

2. Can you go directly from falling leaf to incipient spin?

3. "Back of the drag curve" do the flaps have to be deployed to reach the Back of the drag curve point?

Thanks

mad_jock 4th Aug 2012 19:21

Yep its fully stalled with you fannying around with the rudder pedals trying to keep the wings level.

And yes its the perfect setup for a spin

Nope for each configuration there is a back of the drag curve. Its related to the angle of attack once you go over usually the best glide angle of attack your into the dirty side.

Armchairflyer 4th Aug 2012 19:30


(Genghis): Rudder throughout, but ONLY to keep the aeroplane in balance (in other words no discernable sideforce and the ball in the middle), NOT to pick up a dropped wing.
Why that? My understanding was that picking up the wing with rudder allows sooner application of aileron to roll level, but as always I might be mistaken.

piperboy84 4th Aug 2012 19:30

MJ

Yep its fully stalled
So what determines if you will enter a "traditional" stall or "falling leaf" is it down to individual aircraft characteristics or is it control inputs regardless of what model of plane

mad_jock 4th Aug 2012 19:42

Falling leaf is when you fanny about holding it in the stalled condition dicking about with the rudder to lift wings and other such ****e instead of recovering it.

piperboy84 4th Aug 2012 19:46

Understood, thanks

Genghis the Engineer 4th Aug 2012 19:51


Originally Posted by piperboy84 (Post 7342538)
3. Questions,

1.
Is a "falling leaf" really a stalled condition, and if not what signifies advancing from a falling leaf stall to a full stall condition? and will a falling leaf always progress to a fully developed stall or will you just basically flutter all the way down if inputs are not changed.

The airworthiness standards define the stall as full back stick or an uncommanded pitching and/or rolling motion.

The flight test community would define the stall usually as the high AoA point where the pilot has ceased to have full control in all three axes.

Either way, the falling leaf (which I agree with Jock, is a bloody silly thing to do, not least because it's not a manoeuvre tested during certification, and instructors should not be doing untested manoeuvres with their students) is stupid, but does meet the definition of a stalled condition.


2. Can you go directly from falling leaf to incipient spin?
Yes, typically through failure to maintain zero sideslip during the pitch-up part of this stupid and irresponsible maneouvre.


3. "Back of the drag curve" do the flaps have to be deployed to reach the Back of the drag curve point?

Thanks
Nope, the drag curve just changes shape - you can get on the back of the drag curve in any configuration so long as the aeroplane has enough pitch authority to let you - which almost invariably they will do.

G

Genghis the Engineer 4th Aug 2012 19:58


Originally Posted by Armchairflyer (Post 7342556)
Why that? My understanding was that picking up the wing with rudder allows sooner application of aileron to roll level, but as always I might be mistaken.

Applying rudder for any purpose other than ensuring (near) zero sideslip, increases drag, and increases the risk of spin. If anything it delays your ability to safely use aileron, not brings it quicker.

Unstalling the wing with elevator gives you an unstalled condition, and thus allows you to use aileron.

But there is seldom a good reason to hurry to lift the wing. It's the stalled condition that can give you problems; unstalled, a bank angle is just a bank angle. The 20-30 degrees which is the worst you should see in most aeroplanes after a stall has a trivial effect on stall speed, and you can still climb with it - so sort the bank angle out once the wing is unstalled, and ideally the aeroplane is level or climbing - but not earlier because you don't need to, and applying aileron at too high an AoA can also lead to a spin entry.

G

Pace 4th Aug 2012 20:00

There has been some excellent advice from Pilot Dar CGB Genghis and others.
Most fear is fear of the unknown.
There are two ways to confront fear! slow immersion or extreme immersion so much so that it no longer scares you.
If I stall on my own and make a mistake I may spin. I may get into a situation I cannot handle and then i will die?
This is part of the reason I push for spin familiarity spiral dives and anything the aircraft throws at you RATHER THAN RECOVERY AT INCIPIENT!
My suggestion if this is a real problem is to do a few hours with a good aerobatic instructor in an aerobatic machine. Not to do aerobatics but so you can experience in safety what the aircraft can and will do if abused and how to get out of it to such an extent that fear of the unknown has gone.

pace

piperboy84 4th Aug 2012 20:19


My suggestion if this is a real problem is to do a few hours with a good aerobatic instructor in an aerobatic machine. Not to do aerobatics but so you can experience in safety what the aircraft can and will do if abused and how to get out of it to such an extent that fear of the unknown has gone.
I had the fear issue and did exactly as you suggest here, went to an aerobatic school that specialised in spin recovery and teaching emergency manoeuvres training, it was great learning and a lot of fun. Upon completing the course i thought as soon as i get home I am going to practice stalls etc on my own in my own plane, Funny thing is i still have not tried it, i always seem to give myself excuses not to do it, i think the fear is still there.

Pittsextra 4th Aug 2012 20:26

The original post talks about a fear of stalling and actually you can sympathise with the view given the current PPL (i.e no spin training) and some of the established views (some expressed here).

With the correct training there is nothing to fear from either a stalled condition or the spin. In fact aerobatics will introduce spins which require stopping to the a degree of accuracy to the 1/4 turn at the first stages - so all of this is under control.

The problem is that during the PPL such a big deal is made of the stall/spin that students are left uneducated - in fact most instructors have very little spin knowledge.

Sadly this extends to the military where this fear is re-enforced as they themselves have drilled holes in the ground with a variety of basic trainers.

The only solution (IMO) is do some training with a good aerobatics instructor. Your profile suggest you live in Swindon - so White Waltham is a perfect venue for you to kick off.

Pittsextra 4th Aug 2012 20:31


Either way, the falling leaf (which I agree with Jock, is a bloody silly thing to do, not least because it's not a manoeuvre tested during certification, and instructors should not be doing untested manoeuvres with their students) is stupid,
??? What?? You could fly tomorrow with any number of good aerobatic instructors that could demonstrate this condition at will. Why is it "bloody silly'?

Pace 4th Aug 2012 20:36

Piperboy

But did it make you feel more confident and relaxed having done that aerobatic experience than if you had not?
When I got my PPL I quite happily took friends off on trips into France with a much more experienced pilot with me.
On one occasion my friends turned up we were ready to go and a message came through from my friend who told me he had crashed the car and was unable to come.
I was all for cancelling and got really nervous until my friend assured me I didnt need him to hold my hand.
I was still nervous but bit the bullet loaded my other friends and we had a superb flight there and back which did my confidence the world of good.
In any situation where you know you have someone alongside who can sort things it is a fear in itself to loose that safeguard and go it alone.
That is an equal fear as stall recovery and the only way to deal with it is to go it alone.
FEEL THE FEAR AND DO IT ANYWAY!

Fear is about the unknown get taught recovery to incipient which is the modern trend and there is a lot of unknown there.
Go have fun with an aerobatic machine

Pace

stiknruda 4th Aug 2012 20:43

A CONFESSION
 
FB1971

I learnt to fly in the RAF in the late 70's and then had a 10 year break before I obtained my civvy licence in 92 in a small African country. I aced groundschool & exams, amazed my instructor(ess) with my Nav and did really well in the circuit (hardly surprising really given my not revealed past!). She'd send me off solo for GH - just practice steep turns and stalls as you need to build the hours to qualify for the licence!

I was Łucking terrified of steep turns and stalls ON MY OWN- I don't know what caused this terror! I'd take off from her crop-dusting strip and head off to the nearest cloud and hide behind it, so she couldn't see me! After gentle wingovers and lots of Avgas being burnt, I'd head back and land. Oh it went well Lindsay, I'd say as I filled in the log. I passed my GFT as the examiner sat next to me and I knew he'd not let me kill him!

A few months later I flew with Dennis Spence and he suggested a couple of hours in his Pitts (The Smirnoff Team in Jo'burg). I flew with Rehan VT and VT (a former Silver Falcon and instructor (SAAF's Red Arrows)) explained stalling, spinning so clearly that the knowledge began to dispel the fear.

So my point is - if you are frightened, tell your instructor - if he/she can't help - change instructors!!

Stik

Blog

Dennis features in a recent blog!

Genghis the Engineer 4th Aug 2012 21:09


Originally Posted by Pittsextra (Post 7342632)
??? What?? You could fly tomorrow with any number of good aerobatic instructors that could demonstrate this condition at will. Why is it "bloody silly'?

Presumably those aerobatic instructors are using aeroplanes stressed and tested to carry out aerobatics.

NOT a PA28, C150, Thruster T600, Pegasus Quantum.... .... all of which to my certain knowledge were not tested or stressed for such a manoeuver, but all of which have been used by halfwitted instructors to demonstrate it.

G

Pittsextra 4th Aug 2012 21:20

Thats fair but I'm not sure anyone had talked type before - some one simply suggested get your instructor to demo the falling leaf which then got a hail of "thats silly, dangerous.. etc"

Of course you should respect the limitations of the type your find yourself flying..

Although you did say "not least' so type limitations aside you are fine with the concept?

Pace 4th Aug 2012 21:23

Ghengis

When spin instruction was stopped it was because more aircraft were lost training in spin instruction than for real!
Does that mean students should not be taught spin recovery? NO!
It means the right machine with the right instructor should be used.
Pilots should be familiar with all situations they can get into to be properly trained as pilots.
The author of this thread highlights the poor level of training offered in the PPL at present as well as the other thread regarding fear of forced landings.
Recovery to incipient is just not good enough!
Not just for the reason that they dont know the difference or recovery from a spiral dive or spin but are even scared of stalls for fear of what they may get into if the stall is abused.
We now have got to the stage that Cirrus pilots are told to wreck the aircraft by pulling the chute as they are so poorly trained or current in PFLs and handling that the chute is the best option.

Pace

Genghis the Engineer 4th Aug 2012 21:29

Am I fine with the concept of a falling leaf manoeuver in training?

In an aerobatic aeroplane, for a post-PPL advanced student learning about the corners of the envelope, absolutely fine. We did it on my ETPS course - from memory in a Tucano, and probably the Hawk.

For a PPL student, in a non-aerobatic aeroplane, who needs to build up behaviour patterns that will lead to immediate stall recovery with low height loss. Absolutely not.

Pace>> I am not against taking an aeroplane to a full stall, and believe that students should be taught to recognise the stall, and recovery from it promptly. I am against holding an aeroplane in the stall once it clearly has done - that is either aerobatics or test flying, and is not sensible or useful flight instruction.


G

Pittsextra 4th Aug 2012 21:47

Genghis I'm not being funny but if anyone stalls a PA28 and doesn't realise it then frankly its a case of natural selection in action.

Getting a low time PPL to the point of stall safely isn't difficult, the recognition of which and corrective behaviour is down to the individual.

The OP suggested he was fearful of this state, which IMO is no surprise given the attitude around this subject. Its borderline "sea monsters live beyond 'ere"
and quite silly.

Whilst I absolutely agree with the attitude around type, its perhaps more indicative of the military than the nature of the type of flying that it was only until you are at the ETPS that you explore this element of the flight envelope?

Genghis the Engineer 4th Aug 2012 22:06

I did ETPS as a civilian back-seater, so I don't know first hand what the chaps in the front seat had seen of post-stall conditions prior. That said, given that in my syndicate the two pilots were a Herc driver and an F-18 driver, the odds are that it varied somewhat.

I mostly agree with you - any pilot should recognise the stall, and feel comfortable going there and coming back. I do not, for example, like the typical FAA approach of slow flight only recovering at the warner.

Okay, I'm not PPL student, nor have been for several decades, but I practice stalls most months, increasingly from the right hand seat, and regard them as just something you stay current at, whilst avoiding them if you didn't actually mean to. The "here live dragons" attitude in much (civilian / GA) flight training is indeed silly.

But I remain firmly of the opinion that the first priority in PPL training should and must be recognition and prompt recovery. Taking an aeroplane into the post stall regime should not go outside the cleared envelope, and should generally be regarded as an unnatural act - at that level of training. That doesn't preclude spin familiarisation, but again the emphasis should be, once in a spin, on prompt recovery.

Holding an aeroplane in any post-stall condition belongs in specialist advanced training, using aeroplanes properly certified for the purpose.

G

funfly 4th Aug 2012 22:13

Doing stalls and unusual attitudes under a hood, now that really does concentrate the mind:E


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