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Sydu
20th Jul 2005, 20:29
I know there's more than one way to skin a cat but -

What do you prefer to teach for SSR regarding reducing the AoA & why- I've come across the following two so far;

" Control column neutrally forward to silence the stall warner/ until the buffet stops...."

or-

" Control column centrally forward to set the recovery attitude..."

Obviously this is just one element of SSR. I have my opinion as to which i prefer to teach - I'm interested as to what others think.

BEagle
20th Jul 2005, 21:10
Neither.

Full power and control column centrally forward until whatever told you the a/c has stalled no longer does so.

Then maintain that pitch attitude, roll wings level and recover from descent.

Sydu
20th Jul 2005, 21:15
Thanks BEagle.

How do you find students get on applying that patter?

hugh flung_dung
20th Jul 2005, 21:39
"Stick sufficiently far forward to unstall the wing (ailerons neutral), full power, roll to wings level, nose on the horizon, pitch to climbing attitude as speed increases." flaps and gear as appropriate.
... I know it ought to be "control column" but it's easier to say "stick".

I often find that people lower the nose too much and then leave it down waiting for Vy - fine for an academic stalling exercise but this isn't going to help them if they get into an unexpected low level stall.

HFD

spitfire747
20th Jul 2005, 23:08
control column forward enough until buffet stops.. full pwer balanced with rudder and forward pressure, at Vy nose to the horizon...

always stick forward prior to power going in to be 100% correct.

BingoWings
20th Jul 2005, 23:26
The Pilots Operating Handbook for that aircraft should be consulted with regards to recovery technique. Leading with power could worsen the effect of the stall or even flip the aircraft over (Cessna 152).
SSR technique for training aircraft is control column forward, full power or CC forward together with full power. As HFD has said, students do tend initially to Stuka dive the ground. Recovery with minimum height loss is the objective. I’ve found some aircraft can power out with minimal decreased pitch attitude, others not.

DB6
21st Jul 2005, 07:40
Back to the first post - the first statement is the way to go as there is no 'recovery attitude' as such. The attitude at which stall recovery occurs will differ depending on power, configuration, and depending on what you're doing (e.g. aerobatics) can be literally any attitude. However it will ALWAYS be when the stall warner/buffet stops. I know you are referring to the academic, power off SSR and you could probably teach a particular attitude for that one particular case but it's fundamentally incorrect, and as soon as you move on to stalling in the approach configuration no longer applies.
I rest my case :8, and it's far too early for this stuff, Syd(u) :E :ok: .

FlyingForFun
21st Jul 2005, 10:24
I often find it helps to pitch up until the stall warner sounds, then lower the nose until it stops... then up until it sounds again, then back down. Only a demonstration... but students are often surprised at how little the nose needs to be lowered to stop the stall warner. Can also do the same demonstration actually going into the stall, rather than just waiting for the stall warner. A picture tells a thousand words!

FFF
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blagger
21st Jul 2005, 12:00
Think the original post's second version about selecting recovery attitude is for gliders where power is not an issue. That wording is what we use when teaching in the Air Cadet VGS Organisation on Viking/Vigilant (I know Vig has power but we only stall train at idle power as all approaches are at idle power). As we are only going to first solo standard, giving the kid something simple like selecting a recovery attitude works OK. For SEP teaching I have always been taught as per BEagle's response - and it is normally the buffet that it the first sign of stall so you pitch forward sufficiently to remove that during the recovery.

DFC
21st Jul 2005, 22:11
Stick Forward
Full Power (keep in balance)
Climb (at appropriate speed)

That is the Standard Stall Recovery.

If the student moves the stick forward and then applies full power followed by pitching up to acheive the climb attitude 3 things may happen;

1. They acheive the climb attitude and the climb speed at the same instant - 100% This will be the prompt recovery with minimal height loss

2. They acheive the climb attitude but the speed is way above the climb speed - they are either lowering the nose too much (stukka dive) or are moving the stick forward correctly but delaying the pitch up to climb attitude too long or a combination of the two. This will cause excessive height loss

2. They acheive the climb attitude but the speed is below the climb speed (or worst case they are not accelerating because they are in buffet/high drag) - they pulled back too soon or too hard - They have pulled back too soon or not moved the sick forward enough or a combination of the two. This risks a secondary stall and also causes excessive height loss.

With practice, the student can recover from the stall and safely climb away at the appropriate climb speed with minimal height loss eventhough the airspeed indicator is covered.

-----

and it is normally the buffet that it the first sign of stall so you pitch forward sufficiently to remove that during the recovery

What about aircraft that show little or no signs of aerodynamic buffet and have no stall warning indicator?

Regards,

DFC

fireflybob
22nd Jul 2005, 09:43
>What about aircraft that show little or no signs of aerodynamic buffet and have no stall warning indicator?<

I was always under the impression that part of the requirements for a Certificate of Airworthiness is that the a/c must have adequate stall warning - either buffet or if this is insufficient the a/c must be fitted with a (serviceable) stall warning system.

Genghis the Engineer
22nd Jul 2005, 15:37
BingoWings please accept from me the prize of a virtual mars bar for being the only person to actually mention the POH.

Whilst they're often pretty similar (usually!) I do wonder why people like me who certify and flight test training aeroplanes go to so much effort to get the POH absolutely right, for FIs then to ignore them and use things they call "standard" without reference to the manual.

G

homeguard
23rd Jul 2005, 00:46
The concept of the standard stall recovery was never intended to be a replacement of the particular techniques recommended within the POH. It is, put simply, a very ingenius method which can be added to everyones basic armoury and it will always work. It is a method which will work throughout the normal range of types. When you are teaching anyone to fly it is right to give them a basic concept on which they can later adapt as required for a particular type that they may fly. The word 'standard' is deliberately chosen to mean no more than that.

Centaurus
24th Jul 2005, 13:41
The Founding Fathers who wrote that fine book RAF Air Publication 1979A entitled Elementary Flying Training - (First edition April 1943) under the chapter called "The aircraft and its component parts", have this to say about the controls:

The principle controls are the control column or stick, the rudder bar and the throttle; other subsidiary controls will be referred to later. The stick is so placed that it comes between the pilot's knees".

Right through the book the control column is referred to as "the stick." Why use 13 letters when you can use four letters to mean the same thing?

P.Pilcher
24th Jul 2005, 13:55
To get back to basics - the aim of the lesson is to recover from the stall with the minimum loss of height. Thus you use the technique which gives this. It will differ from A/C type to A/C/ type.
The lesson will doubtless include different recovery techniques to show which is the best to satisfy the aim. er - or am I out of date?

P.P.

Charlie32
26th Jul 2005, 11:09
Centaurus

To be picky its 5 letters, and in many aircraft nothing like a stick between your knees!

MVE
29th Jul 2005, 23:11
'Standard Stall Recovery'

1 Stick centrally forward to unstall the wing
2 Full power to reduce hight loss
3 Prevent/reduce wing drop if it occurs with opposite rudder
4 When all signs of the stall have ceased nose to the horizon then climb away if necessary when speed increases

1. Centrally forward to reduce chance of wing drop possibly leading to a spin but PRIMARILY TO REDUCE THE ANGLE OF ATTACK which is why you are stalling in the first place

2 Full power to reduce hight loss. THIS WILL NOT STOP YOU STALLING AS YOU STALL DUE TO EXCESSIVE ANGLE OF ATTACK - student not convinced? show them a stall and don't use power to recover - amazing! the aircraft still recovers just loses more hight

3 Use the secondary effect of rudder to prevent the wing dropping further as trying to use aileron will only increase the angle o attack further and lead to further wing drop etc

4 Raise nose to horizon when stall has ceased (assuming your not in the process of finding a field because of engine failure) climb away if required

That's how I teach it and was taught to teach it. Hope that helps