Power on Stalls

[mstram]

I was reading someone's pilot training blog (based in U.S.) (ya I need to get a life), and they were describing their experience with power-on stalls.

The procedure being taught was to apply full power, while climbing at
Vx, then apply backpressure until the plane stalled.

I'm wondering if that is the standard / FAA / flight school s.o.p. ?

Wha is the technique used in the U.K .. or other countries?

In the U.S. is there a set syllabus that flight schools / instructors have to
follow? ... or is just a matter of covering what is required on the
flight test? (is this technique tested on the flight test?)

I'm in Canada, and in my flight training, power-on stalls were performed
at ~1700-1800 r.p.m. with 10deg flaps (C172).

While I can see some benefit to the "full power Vx" stall, as it
apparently is aimed at training how to recover from a stall at takeoff or from a go around, it also seems that it might be verging on the "whip stall" manouver (that I've never really seen a good definition for btw), which are
prohibited in the C172 p.o.h. It would also seem to be, a pretty violent
stall (I've personally never tried one with that technique).

comments ?

Mike

[Centaurus]

That is totally unnecessary dangerous flying. A power-on stall only needs to be done in the approach configuration with landing flap down and a trickle of power between 1200 and 1500 rpm. Recovery action is normal. Sounds like some idiot is out to kill you!!

[greeners]

Centaurus - So do you feel there is any value in examining what happens when the student raises the nose (far) too high on the climbout?

[hugh flung_dung]

There are 4 stall configurations on the current LST/LPC form: idle/clean, final turn, approach, and departure. The first is held until it develops and the examiner calls for recovery, the others are recovered at the incipient stage.
The technique for the departure stall is simply to set-up in take-off configuration at around Vx, then to set-up an unusually high nose attitude and wait until there's a stall indication - obviously this is done at a safe height and after the appropriate checks. Recovery is simply to prevent further yaw and relax the back pressure. Generally it's a ho-hum exercise but there's an obvious risk if continued beyond incipient with significant yaw.

I've also not seen an authoritative definition of a "whip stall", but I've always presumed it was a loose term for an accelerated stall.

HFD

[homeguard]

A stall in the climb is part of a UK/JAA Instrument rating course and is tested. i.e. 'Recovery from unusual attitudes'.

[Runaway Gun]

It's not a whip stall, simply a stall with lots of power on. And because it's done at 1G, it's not accelerated in any fashion. Safe as houses !!

I have taught many students things that are not in the syllabus, simply because they were highly realistic scenarios that other instructors did not have the willingness (or experience) to demonstrate.

Find an appropriate Unusual Attitude experienced instructor, and learn how to efficiently and safely recover from ANY 3D position. The training will be invaluable whether you then go on to fly a C150, Lancair, or B757.

[spernkey]

i spend 600-1000 hours a year in 172's flying at 40-50% power 10 deg flap and 60-70 kts taking pictures. The hours builder who sits next to me needs to understand how far/close he is to the stall and how the plane feels in slow flight with power on.
As a previous poster says approaching the power on stall gradually is fairly benign and necessary. Published stall speeds of 54kts power off translate to nearly nil airspeed on full power with a ROC of 10 feet a year.
Freind of mine "Reversed" his cesspit into trees after the wx clamped in over inhospitable terrain. Saved his life. Probably best for most to stick to the envelope they believe in though.

[Dude~]

After a couple of hundred hours instructing I went up one nice summer evening with a friend to see if I could make the PA28 do anything remotely exciting. Tried stalling with full power and couldn't. Maybe if I'd held it there for long enough it might have slowed down. Oh the joys of low hours confidence..:uhoh:

[Runaway Gun]

Oh please let me come and have a go. I reckon I could stall it with the power on :}

Might have to get you to sit in the back though :)


Did you try it when out of trim (rudder)? That normally gets the world looking exciting. And that's how people tend to get bitten, looking over their shoulder, trying to turn back etc...

[Whopity]

There are 4 stall configurations on the current LST/LPC form: idle/clean, final turn, approach, and departure. The LST/LPC form does not identify them but the examiners record SRG1157 does. This is copied from App 3 to JAR-FCL 1.240 however, the "departure" stall is not listed as a mandatory test item and according to the form should be covered in training!

If you look at the training syllabus AMC-FCL 1.125 there is no mention of such a manoeuvre!

[BigEndBob]

mms://media.americanflyers.net/asf/AF_FAA_Stalls.asf
http://www.americanflyers.net/resources/faa_videos.asp

Don't know how many times this film as been copied (probably exists recorded in all formats from cine to dvd) but worth a look!

Seem to remember the highly uncoordinated steep turn to stall in PA28 140 produced the sort of manouvre a Sopwith pilot would be proud of!

[hugh flung_dung]

Whopity: that's a bit of a nit pick old chap. ;)
For the avoidance of doubt, the full title of the "examiner's record" and the application form are "Form LST/LPC SPA, Skill Test Issue 3 (SRG\1157)" and "Form LST/LPC SPA/MPA Issue 8 (SRG\1119)" respectively.

I don't doubt what you say about FCL but according to the guidance attached to 1157 the requirement is for a fully developed stall plus one of the other 3 at the examiner's discretion.

HFD

[Baron Von Mildred]

I'm a JAR instructor, currently teaching on the Ikarus C42. For those unfamiliar, this is a microlight 3 axis i.e. a normal light aircraft, except very light... It has 100 hp which may not sound a lot, but with less than 450kgs to haul, makes this maneuvre more dramatic than just about anything except probably a high power aerobatic aircraft.

Teaching the departure stall results in near vertical pitch angles.... interesting!

[Whopity]

HFD

My point is that you can request it but the teaching of it is NOT in the published syllabus! Just proves how unjoined up the writing is!

[llanfairpg]

Please advise me where an official syllabus states the power setting to be used for Ex 10?

[BigEndBob]

Pre JAR the idea was to teach students to recover from all types of stall (including spins) then leave it up to the examiner to decide what to test.
Now we seem to be worrying about exactly what type of stall and technique is required to pass the JAR test. Its turned into the CPL test. Monkey see monkey do.

My pre JAR tests were more demanding as much more was covered in the flight test. Not to say we can't do the same now except you cannot fail someone who might do a bad recovery from say a steep turn stall, or poor climbing IF.
A candidate did not just pass or fail, an overview of the students ability was taken into account and a judgement made. Its still done now but with fixed fences to jump over.

[VFE]

It's good to see continuity across the board amongst instructors as always on PPRuNe! ha :rolleyes:

Seriously though, an awful lot cannot be taught on an FIC course (time restrictions, etc) but when you actually get into the job you begin to discover just how little continuity amongst us all there really is! I guess there's little that can be done for this issue other than an active input from CFI's and experienced instructors and a fuller, more thorough, syllabus/guidelines for instructors. Perhaps the instructor seminars create some sort of unity?

Everywhere you go things are taught and done differently and it kinda grates on my nerves somewhat that this state of affairs exists - the amount of students I've flown with who have said "ooh, that's different from the last instructor I flew with".... some of that you can put down to student misunderstanding but a lot is down to us all teaching in our own way. As long as we don't reinvent the wheel I guess it's not so bad but getting back on topic....

Full power on stalls and recovery at JAA PPL stage? It's not in the syllabus and certainly not something I teach.

VFE.

[The Otter's Pocket]

VFE
Although it isn't taught as part of the PPL course my CFI told me to show a student what the stall is like. Here is why.

The stall scenario is on the approach to the runway. Flaps, medium power setting and pulling too hard. On the PPL and CPL you recover at the incipient stage, ie buffet or stall warner.
However if you take the aircraft further into the stall then it could depart into a spin or a spiral dive. The wing drop is very marked. (As I found out on my mutuals).

It is very important to show a student why we recover at the incipient stage.

I have been led to believe that the Cessna that crashed and killed a young lad on a solo flight in the summer was caused by the A/C departing controlled flight.

If an instructor is worried about flying the sortie, ask for a demonstration from the CFI it may save your life.

[Baron Von Mildred]

Llanfairpg

Its unlikely a syllabus will quote any specific power setting for a type of stall, because this will vary according to aircraft & engine type. However if an instructor was wishing to teach recovery from a stall in the departure phase, to be realistic, this would need to be done with full power, as on most GA aircraft that is what is used on climbout.

Some aircraft are more prone to this type of stall than others. For some the angle of attack required can easily be accidently reached being not that great. Having said that I have have students nearly stall an Ikarus C42 after take-off, by just having no sense of reality about the kind of pitch angle required and pulling back to near vertical!!

[Airbus38]

Just my two penneth here,

My opinion would be to think about the aircraft you're flying. If the aircraft is going to do something dangerous in a full power stall, then it's probably for the best not to do it, but a thorough brief to the student should be advisable, and plenty of stall/spin prevention training. If it's not particularly dangerous at height, then why not extend the ability of the student? One of the major causes of fatalities is the departure stall, and this is virtually always a full power situation.

To say that the recovery action should be taken at the incipient stage is a little bit strange to me. If the 'incipient stage' is always recognised, why do stalls occur? Please don't lose sight of the fact that not all aircraft buffet significantly prior to the stall, not all aircraft have stall warners, and a stall warner may or may not work when needed. The 'incipient stage' in some aircraft may only manifest itself as a reduction in airspeed, and many aircraft climb very close to the stall itself!

[Baron Von Mildred]

Good points Airbus38. Wish I had said it myself...

[foxmoth]

Try this for a likely scenario - Full power climb out, nose too high so the speed is low - and then retract the flaps. This is the sort of error it is only too easy to make.:eek:

[VFE]

VFE
Although it isn't taught as part of the PPL course my CFI told me to show a student what the stall is like. Here is why.

I agree that this should be demonstrated as it is indeed part of the syllabus but it was my understanding that this thread was discussing demonstrating full power stalls to a PPL student.

On final approach the power is usually below 50%.

Also, I agree that it would be very useful to explain to a student why retracting flap on take off ergo full power stall is a dangerous scenario but the requirement to actually invite danger to myself and student by demonstrating it is not so necessary IMHO. You don't need to stick someones hand into a fire to inform them that it'll hurt.

There are better ways of bringing gun-ho students down a peg or two than quasi-aerobatic stalls which unless you've been properly trained yourself is highly irresponsible and could end in tears. Installing a proper understanding on the ground in front of the whiteboard, impressing the dangers onto the student with scary tales of fallen fellow flyers should suffice unless they're thick as sh*t.... in which case you should ask yourself whether flying is something you ought to be teaching them anyway!

VFE.

[Runaway Gun]

I agree that it should be done safely - with a competant and confident instructor, at a suitable height. But simply talking about it won't hammer the point...

Think of the money we could save students simply by talking about flying.

Then again, they'd probably have to buy our beers. ;)

[FormationFlyer]

OK lets put this to bed.

Examine this document

http://www.caa.co.uk/docs/33/FORSRG1157.pdf

As you can plainly see during an SEP skills test us examiners CAN ask for this type of stall from the student.

In general you will only find this in JAR-FCL in the syllabus per se for IR(A) and CPL/ATPL. However, as we examiners can test it for SEP class ratigns (which is what the JAR-PPL skills test includes) - I therefore suggest that ALL instructors teach incipient recoveries from this position - anyway the incipient is a no-brainer anyway...far less interesting than the full developed stall :) <grin>

I certainly added this to Ex10B.2 to cover this eventuality after one of my students had an examiner ask them to demonstrate this sort of recovery.

VFE You should read the accident statistics and GASIL more often - climb-out spin-ins are more common than you may think - this is exactly the situation we are talking about demonstrating here. quasi-aerobatic? No. Sensible training. We are trying to stop a number of climb-out spins occuring here.

WRT dangerous...try a C152 with full flap and full power - i.e. a very botched go-around - and yes I have seen a student do this to me before..tell them to pull the nose to the Vx climb rather than the Vy simulating a botched go-around from a strip with obstacles. The result if allowed to go fully developed is fairly impressive - and I use this to teach Ex11A. Which of course you DO all teach EX11A dont you...

Just some thoughts...

[2R]

Excellent and very good points in this thread so far ,
The main purpose of the exercise is Recognition and Recovery
As much fun as it is to fly a stalled aircraft in training ,as you really have to force it to stall as most modern trainers are designed not to stall and requires a lot of effort to keep it stalled .
The experience of flying a stalled airplane and the recovery process comes in handy if you ever get caught in turbulant air that is trying to stall the aircraft at it's cruise airspeed and throw you out of the sky.I have heard the stall horn come on at cruise speed in turbulance and have had to use the smoothest of control imputs to keep the greasy side down.
It can be a challenge to keep the airplane below manuevering speed and well above the stall speed when the stall horn is blaring as the airflow violently changes around the wing.The gentle introduction of the violent stall characteristics of your aircraft will save your bacon if you get caught on the wrong side of a mountain wave or valley inflow /outflow or if you are unlucky to find yourself in a CB.
It's all about getting skills that you hope you never need

[Runaway Gun]

Good points 2R, excpet for your comment about the 'challenge' to stall a modern aircraft.

People keep stalling them by mistake, regardless of configuration, power, AOB, time of day, generally at a height not sufficient for recovery, and they pay the price for it. Half of them probably never figured out what was happening.

And the so called magical 'stall speed' is only a 1G speed, with the slip ball in the centre.

In my opinion (and I've been through both civilian and military flying training) these more extreme stalls should be practised - in an aerobatic aircraft if neccessary.

[llanfairpg]

g ,as you really have to force it to stall as most modern trainers are designed not to stall and requires a lot of effort to keep it stalled .



I have been watching this thread for awhile and its interesting to note the ignorance that abounds. The quote above is a classic example of a statement which is vague, incorrect and misleading and if you are an instructor i would suggest you do not instruct again untill you do some re-training, in fact if you were a student and demonstrated that poor level of understanding i would not allow you to fly solo

Using your quote perhaps you should approach the CAA and ask them to remove stalling from the syllabus as its obviously no longer a concern.

Airbus, would you like to list the types of aircraft that mangaged to get CAA approval and registration in this country that do not have warning of an impending stall. I think what you meant was that some aircraft have sufficient aerodynamic warning of an approaching stall that they do not need a mechanical or electrical warning of the stall. Saying that some aircraft do not have warning of a stall is ridiculous, saying that some electrical or pneumatic stall warners can become unservicable and surpise pilots who were unaware of the need to preflight these items might be more useful

What is the problem with stalling a light aircraft with full power at a safe altitude anyway? In my experience its only been the fear of the instructor thats prevents high power stalls. When you think that the aircraft you are training on is most likely approved for spinning and that I would suggest is a little bit vicious than a full power stall, what is the problem?

When talking about a PPL syllabus consider that any flying school owner/CFI can write his/her own syllabus with any type of power stalls or configurations. If there was a statement in the flight manual that cautioned or prevented full power stalls that would be different.

The important thing to get over to the student is that an unintentional stall at low altitude, such as in the circuit, is very likely to be terminal. The way each instructor teaches this will obviously vary but it needs a liitle bit more care than is given by the 'tick in the box' instructor. It is the one exercise that the student needs to understand completly and be able to show 100% capability.

What is required in a test is not the same as is required in a syllabus of training, unless of course you are the sort of instructor who trains only for the test.

in my experience it would help if instructors left folk lore in the bar and actually read and practiced the syllabus they are employed to teach rather than introduce their own modifications mainly based on laziness and ignorance.
Amen

[2R]

The power on stall is called a departure stall in the USA.
I stand by what i said and find your comments about ignorance to be rude and discourteous. Hardly the type of language that is constructive or expected on a professional pilots forum.
Where we do agree is the fear that some instructors have of the stall .
IIanfairpg for some reason you think your opinion has more value that the others on here .Why is that ? :8
Up yer Kilt

I used to try and cure the fear that my new instructors had of the stall by playing them a nice tune on the stall horn (power off)
and flying the airplane fully stalled (at a safe height).
The important part is the recovery and i will not bore you with that as most of you know that it is important to unload the wing and and power up smoothly anticipating the effects of power on the aircraft attitude at slow speeds and controlling the expexted yaw before it becomes .
Go to go i think it is my shout at the bar Cheers

[Airbus38]

"...not all aircraft buffet significantly prior to the stall, not all aircraft have stall warners, and a stall warner may or may not work when needed."

That's what I said, and I stand by that. To clarify, when I say "stall warners" I mean, for example, an audible device, a stick shaker etc. to warn of the impending stall. In that respect, my statement is true. Not all aircraft have stall warners.

Not all aircraft do buffet noticeably before the stall has developed to a situation where the SSR must be employed rather than an incipient recovery. Also true.

My comment that the "stall warner" may or may not work when needed is just an aside. Yes, I would advocate checking the buzzer makes a sound pre-flight, and indeed do. If I was flying and noticed that my airspeed was low and attitude was higher than it ought to be, however, I would not think this OK just because I couldn't hear the buzzer, nor would I expect that anybody else would. It's a back-up, and my point is that its unserviceability should not (talking specifically of light primary trainers) mean the difference between a stall or not.

Maybe my previous paragraph is a matter of opinion, but please don't call me ridiculous for stating facts that I know to be true.

I agree with the rest of the things you say, however, you seem to have summed up the answer to the original question as I see it.

[homeguard]

The last post is quite correct a number of aircraft do not have a stall warning device nor a particularly obvious indication of the impending stall such as a buffet etc., the Piper PA24 Comanche being one. Sloppy controls and poor response still remains the best warning. Attitude - take care with that one. Attitude v what?
As for the checking the stall warner function when fitted. There is little the pilot can do other than check if the thing works; moving it by hand in the case of the micro-switch variety or by sucking through a hanky in the case of the type fitted on many Cessna. But this doesn't check the setting is correct. If the setting is incorrect the warner could activate far too early with no meaning or far too late.
EASA in its wisdom has removed the requirement of the C of A test flight which was conducted by pilots approved by the CAA. Expect to find an increasing number of mis-set stall warners.

[Airbus38]

Attitude - take care with that one. Attitude v what?


I know, I agonised a little over how to sum up the best way to describe how I would normally detect an incipient stall. I went for "attitude was higher than it ought to be" which i concede is sloppy, but true for your majority of situations.

Quite right for picking that up though.

Agree 100% about the stall warner. You can check it makes a noise, but it's a bit like a smoke alarm...pushing the button only reveals it responds to 'finger' and not to smoke!

[RVR800]

Stalls on full power do feature in accidents (take-off with high weight usually; edge of performance envelope) - why not teach students to recover - its just a bit of basic rudder and stick after all!

The FAA are just using common sense (something lacking in the JAA world sometimes):yuk:

[oscarmike]

Hi All

I have been reading this thread with interest.

Even though I am NOT an instructor, can I pass on a personal experience?

Low hours PPL (Me, no IMC) flying over Bodmin moor on the way back from Scilly, 3500' with broken cloud at 2500' - in sight of ground so perfectly legal. I could see at least 30 miles ahead that the ground was illuminated by sunlight, so no risk of the cloud closing in under me.

Then about 4 miles ahead I saw a patch of rising cumulus cloud with a V shaped top whichI reckoned the top of which was maybe another 500'

No problem, thinks I, and puts on full power and easing back on the stick, I'll just go over the top of it.

I was watching the approaching cloud and hadn't even glanced at the instruments for some minutes.

The next thing I knew, I had entered the cloud, completely white out, with the stall warner blarting!

Couldn't be much worse, non IMC in a full power on stall in cloud!

I panicked and pushed the stick forward, and for some reason still unknown to me banked to the right. Fortunately we broke out of the cloud i a few seconds and I was able to roll level and back under control.

However, I could have easily entered a spin.

It took me a good 20 minutes to stop shaking.

Lesson learnt the hard way, and I am now IMC rated!

Just goes to show it can happen...............!:=

regards

OM

[2R]

Run away from clouds if you are not instrument rated as the stains can be hard to get out of the seats :} :}
Wait until your radar craps out and you are getting tossed around like a rag doll in a CB ,i do not know what is more scarey the lightning or the up and downdrafts .Lots of speedbumps in some clouds i guess that why they made a new and improved tide with stainbuster