Instructors teaching full rudder to "pick up" dropped wing.
Thread Starter
I think that stalling is often taught poorly because the instructor was taught poorly and so is not comfortable with stalling (I think that is far more common than instructors who want to show off to the student).
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Agree
Generational "dumb down" training inevitably results in a reduction in skill levels across all disciplines (Pilots, Instructors, Trainers, etc etc)
The argument that because we don't permit, and therefore don't need to train for a spin event will be of little comfort to anyone who inadvertently finds themselves in such a scenario without the tools and training to recover.
Generational "dumb down" training inevitably results in a reduction in skill levels across all disciplines (Pilots, Instructors, Trainers, etc etc)
The argument that because we don't permit, and therefore don't need to train for a spin event will be of little comfort to anyone who inadvertently finds themselves in such a scenario without the tools and training to recover.
There are aspects of this discussion that disturb me, including dangerously incorrect statements by some posters, so a few bullet points to ponder:
A wing stalls when the critical angle of attack (stalling angle) has been exceeded on that wing. In the training situation, the classical focus is on the situation where both wings stall at the same time. A wing drop at the stall is invariably caused by one wing stalling before the other. This “uncommanded roll” may have been caused by:
Teaching recovery from a stall with a wing drop has classically involved what came to be known as the “standard stall recovery”:
· Ailerons neutral
· Reduce the angle of attack with elevator (stick forward)
· Simultaneously apply full power (if available)
· Sufficient rudder “to prevent further yaw”
Over the years, in some quarters, this last point has been translated into “pick up the dropped wing with rudder”. To “pick up the wing” requires yaw in the other direction and as the aircraft is still close to the stall, it may well result in the opposite wing stalling. The technique is used in certain aerobatic manoeuvres such as the “falling leaf” where the aircraft angle of attack is held just off the stall and the pilot applies rudder one way and then the other to stall one wing then the other. As a basic stall recovery technique, it is potentially dangerous.
Significantly, the military moved away from using rudder “to prevent further yaw” years ago as it was “negative training” for future aircraft types. Extensive trials were conducted on light piston training aircraft as well as on turboprop and pure jet trainers to look at height loss during stall recovery. Interestingly it was discovered that use of rudder to prevent further yaw had absolutely no effect on height loss – and even could distract the pilot from simply using elevator to un-stall the wing or wings and then using aileron to level the wings when the aircraft was no longer stalled.
A number of modern aircraft – some of which are used for training (e.g. Cirrus) have design features that allow ailerons to be used at the stall (such as marked washout or chord twist that causes the inboard section of the wing to stall well ahead of the outboard section containing the ailerons). However, the licencing system allows a pilot to fly any type of light aircraft and I'd suggest that the concept of “primacy” will prevail in a startle / surprise situation that would almost certainly be present in an inadvertent stall. This would result in a pilot reverting to whatever had been drummed into them during training. If this involved use of aileron, it is likely to lead to very bad outcomes in an aircraft that does not have the design feature.
Bottom line is that elevator is the primary control to un-stall the wing(s). Use of aileron or rudder can be problematic near the stall – more so in some types than others. Teaching use of rudder to “pick up a wing” at or close to the stall is dangerous.
Fly Safe
PJ88
A wing stalls when the critical angle of attack (stalling angle) has been exceeded on that wing. In the training situation, the classical focus is on the situation where both wings stall at the same time. A wing drop at the stall is invariably caused by one wing stalling before the other. This “uncommanded roll” may have been caused by:
- Yaw being present as the stall was approached. This could be perhaps be due to change of engine torque. In a training situation, students (and instructors) often fail to correctly balance with rudder when reducing power to enter a clean stall or when applying power during recovery. I also see lots of pilots controlling direction on finals by over-use of rudder, rather than using it correctly to balance the aircraft.
- Differential condition of the wing(s) e.g. ripples in the surface; dents in the leading edge; rigging differences in the wing or the flaps / slats; on a laminar flow wing (such as a glider) even bug squash on a leading edge that results in airflow breaking away (stall) at a lower angle of attack that on the other wing.
Teaching recovery from a stall with a wing drop has classically involved what came to be known as the “standard stall recovery”:
· Ailerons neutral
· Reduce the angle of attack with elevator (stick forward)
· Simultaneously apply full power (if available)
· Sufficient rudder “to prevent further yaw”
Over the years, in some quarters, this last point has been translated into “pick up the dropped wing with rudder”. To “pick up the wing” requires yaw in the other direction and as the aircraft is still close to the stall, it may well result in the opposite wing stalling. The technique is used in certain aerobatic manoeuvres such as the “falling leaf” where the aircraft angle of attack is held just off the stall and the pilot applies rudder one way and then the other to stall one wing then the other. As a basic stall recovery technique, it is potentially dangerous.
Significantly, the military moved away from using rudder “to prevent further yaw” years ago as it was “negative training” for future aircraft types. Extensive trials were conducted on light piston training aircraft as well as on turboprop and pure jet trainers to look at height loss during stall recovery. Interestingly it was discovered that use of rudder to prevent further yaw had absolutely no effect on height loss – and even could distract the pilot from simply using elevator to un-stall the wing or wings and then using aileron to level the wings when the aircraft was no longer stalled.
A number of modern aircraft – some of which are used for training (e.g. Cirrus) have design features that allow ailerons to be used at the stall (such as marked washout or chord twist that causes the inboard section of the wing to stall well ahead of the outboard section containing the ailerons). However, the licencing system allows a pilot to fly any type of light aircraft and I'd suggest that the concept of “primacy” will prevail in a startle / surprise situation that would almost certainly be present in an inadvertent stall. This would result in a pilot reverting to whatever had been drummed into them during training. If this involved use of aileron, it is likely to lead to very bad outcomes in an aircraft that does not have the design feature.
Bottom line is that elevator is the primary control to un-stall the wing(s). Use of aileron or rudder can be problematic near the stall – more so in some types than others. Teaching use of rudder to “pick up a wing” at or close to the stall is dangerous.
Fly Safe
PJ88
Bottom line is that elevator is the primary control to un-stall the wing(s). Use of aileron or rudder can be problematic near the stall – more so in some types than others. Teaching use of rudder to “pick up a wing” at or close to the stall is dangerous.
If AoA is the problem.... AoA is the solution.
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Good advice:
Ailerons neutral and unstall the wing (reduce the AoA by pushing the stick forward). Stalling is ONLY an angle of attack phenomena and can occur at any airspeed or attitude.
Add power as required - maximum may be needed
Then apply sufficient rudder only to stop further turning (AFTER the wing is unstalled)
Applying rudder too early (when at least one wing is stalled) creates a yaw moment that can make the situation far worse.
Unfortunately, I suspect the outcome of the Swan river event may not have been different even if this technique was followed, due to the low entry altitude.
Ailerons neutral and unstall the wing (reduce the AoA by pushing the stick forward). Stalling is ONLY an angle of attack phenomena and can occur at any airspeed or attitude.
Add power as required - maximum may be needed
Then apply sufficient rudder only to stop further turning (AFTER the wing is unstalled)
Applying rudder too early (when at least one wing is stalled) creates a yaw moment that can make the situation far worse.
Unfortunately, I suspect the outcome of the Swan river event may not have been different even if this technique was followed, due to the low entry altitude.
When I’m exercising the privileges of my USA CPL I do what the enlightened FAA says on the subject per their updated Airplane Flying Handbook https://www.faa.gov/regulations_poli...06_afh_ch4.pdf “Maintaining Aircraft Control: Upset Prevention and Recovery Training”
Their stall recovery template is quite straightforward. If progressing to a spin then use the spin recovery template.
It seems that they have realised that for FAR 23 airplanes, when tested for stall behaviour, the power is not changed until after recovery from the stall.
I was at a flying school recently when CASA asked about this subject and my answer was that we do it per their Flight Instructor Manual – why would I do it any differently. In Chapter 13, for recovery from an incipient spin:
· “recovering by ensuring the throttle is closed and the controls are centralised followed by recovery from the ensuing unusual attitude” but on the following page
· “As soon as the aeroplane has stalled and commenced to yaw take the appropriate recovery action. Increase power, apply sufficient rudder to prevent further yaw and ease the control column forward sufficiently to un-stall the aeroplane.”
CASA does not define an incipient spin however it is required per the Part 61 MOS “execute an incipient spin manoeuvre from the following flight conditions and, using correct recovery technique, regain straight and level flight”.
This correct recovery method must be per the CASA Flight Instructor Manual – "increase power" …… “sufficient rudder” becomes full rudder …. easing the control column forward …… but which of the two CASA techniques?
Their stall recovery template is quite straightforward. If progressing to a spin then use the spin recovery template.
It seems that they have realised that for FAR 23 airplanes, when tested for stall behaviour, the power is not changed until after recovery from the stall.
I was at a flying school recently when CASA asked about this subject and my answer was that we do it per their Flight Instructor Manual – why would I do it any differently. In Chapter 13, for recovery from an incipient spin:
· “recovering by ensuring the throttle is closed and the controls are centralised followed by recovery from the ensuing unusual attitude” but on the following page
· “As soon as the aeroplane has stalled and commenced to yaw take the appropriate recovery action. Increase power, apply sufficient rudder to prevent further yaw and ease the control column forward sufficiently to un-stall the aeroplane.”
CASA does not define an incipient spin however it is required per the Part 61 MOS “execute an incipient spin manoeuvre from the following flight conditions and, using correct recovery technique, regain straight and level flight”.
This correct recovery method must be per the CASA Flight Instructor Manual – "increase power" …… “sufficient rudder” becomes full rudder …. easing the control column forward …… but which of the two CASA techniques?
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djpil,
Notice that they focus (2) on unstalling the wing by reducing the AoA - the rest follows once the aircraft wing is below the stalling angle of attack.
The Australian CASA documents are way too confusing and given there is no incipient spin training in a standard syllabus, this really needs to change.
But the Australian regulator of course knows best and knows much more than the FAA (not)
Notice that they focus (2) on unstalling the wing by reducing the AoA - the rest follows once the aircraft wing is below the stalling angle of attack.
The Australian CASA documents are way too confusing and given there is no incipient spin training in a standard syllabus, this really needs to change.
But the Australian regulator of course knows best and knows much more than the FAA (not)
given there is no incipient spin training in a standard syllabus, this really needs to change.
https://www.casa.gov.au/sites/g/file...ad/vfras02.pdf
Have a read.
Then apply sufficient rudder only to stop further turning (AFTER the wing is unstalled)
How about we actually READ what the manufacturer says rather than regurgitating opinions...
At least one incipient spin is also shown here in the CASA flight examiner guide, under PPL test...
https://www.casa.gov.au/sites/g/file...f?v=1532654477
https://www.casa.gov.au/sites/g/file...f?v=1532654477
The Day VFR syllabus is long gone. It is now the Part 61 MOS
2.2 A5.2 – Recover from incipient spin This element only applies to single engine aeroplanes.
(a) perform pre-manoeuvre checks for an incipient spin;
(b) recognise an incipient spin;
(c) use the aeroplane’s attitude and power controls to execute an incipient spin manoeuvre from the following flight conditions and, using correct recovery technique, regain straight and level flight with height loss commensurate with the available altitude (simulated ground-base height may be set):
(i) straight and level flight;
(ii) climbing;
(iii) turning.
The POH extract above is for the fully developed spin recovery. Applying full opposite rudder at the incipient stage has already been discussed.
2.2 A5.2 – Recover from incipient spin This element only applies to single engine aeroplanes.
(a) perform pre-manoeuvre checks for an incipient spin;
(b) recognise an incipient spin;
(c) use the aeroplane’s attitude and power controls to execute an incipient spin manoeuvre from the following flight conditions and, using correct recovery technique, regain straight and level flight with height loss commensurate with the available altitude (simulated ground-base height may be set):
(i) straight and level flight;
(ii) climbing;
(iii) turning.
The POH extract above is for the fully developed spin recovery. Applying full opposite rudder at the incipient stage has already been discussed.
Problem is the definition of an incipient spin is not clearly stated as far as I can see in the Australian documentation.
Some interpret it has a stall with some yaw present, others as the initial stages of a spin until the spin becomes stable (in the aircraft I use this is around 2 complete turns).
Some interpret it has a stall with some yaw present, others as the initial stages of a spin until the spin becomes stable (in the aircraft I use this is around 2 complete turns).
flight test.
Given the talk about picking up a wing I thought this B-52 bit interesting.
Maintain wings level attitude with lateral control as the stall is approached. Fairly large lateral corrections may be necessary. Caution should be used because lateral control capability decreases rapidly as the stalling speed is approached. Rudder may be used to maintain heading; however, during low speed flight, a delay in aircraft response after control input of up to 3 seconds may exist before roll correction develops.
The stall characteristics of the aircraft will vary with wing flap extension and drop tank installation. The following stall characteristics can be expected: With flaps extended and no drop tanks installed, there is little or no stall warning speed margin. Buffet of the flaps when the stall is approached will mask aircraft buffet. At stall, the aircraft will tend to fall off on one wing. This fall-off can be stopped by applying forward pressure on the control column and by using whatever lateral control and rudder is required. As lateral control degrades rapidly at speeds below initial buffet. the use of rudder may be necessary to correct for bank angle.
The stall characteristics of the aircraft will vary with wing flap extension and drop tank installation. The following stall characteristics can be expected: With flaps extended and no drop tanks installed, there is little or no stall warning speed margin. Buffet of the flaps when the stall is approached will mask aircraft buffet. At stall, the aircraft will tend to fall off on one wing. This fall-off can be stopped by applying forward pressure on the control column and by using whatever lateral control and rudder is required. As lateral control degrades rapidly at speeds below initial buffet. the use of rudder may be necessary to correct for bank angle.
The flight test crew who do that testing are the same people who write the words for the POH. They follow what it says in the FAR 23 Flight Test Guide which defines a spin as “A sustained autorotation at angles-of-attack above the stall.” So, if in a spin per that definition then use the spin recovery procedure in the POH.
Incidentally, the term “incipient spin” is not used in the FAR 23 Flight Test Guide however it does state that "Most airplanes will not attain a fully developed spin in one turn."
It goes on to state: “Normal category airplanes must recover from a spin in no more than one turn after the initiation of the first control action for recovery. For example, if you are spinning left with ailerons neutral, recover by reducing power to idle, if not already at idle, apply full right rudder followed by forward elevator.” That would be from an incipient spin.
“For the purpose of this discussion, we will divide the spin into three distinct phases. These are the entry, incipient, and steady phases. ……. in the entry phase, recovery from or prevention of the spin is as simple as normal stall recovery since, in fact, at this point that's all we are really faced with. Coordinated use of rudder and aileron to oppose any tendency to roll should be applied with emphasis on the rudder due to its generally more powerful influence at this point. This should be accompanied by relaxation of elevator back pressure to reduce the angle of attack below that of the stall. Coordinated use of all controls should then be applied to return to normal level flight.
……..
During this incipient phase, spin recoveries in those airplanes approved for intentional spins are usually rapid, and, in some airplanes, may occur merely by relaxing the pro-spin rudder and elevator deflections. However, positive spin recovery control inputs should be used regardless of the phase of the spin during which recovery is initiated.
Briefly, these control inputs should be 1) neutral ailerons and power off, 2) full rudder opposite to the direction of rotation, 3) just after the rudder reaches the stop, elevator briskly forward to break the stall, and 4) as rotation stops, neutralize the controls and recover from the resulting dive.
……..
The final phase is the fully developed ''steady" phase. Here a more-or-less steady state spin results where the autorotational aerodynamic forces (yaw due to rudder deflection, lift and drag differences across stalled wing) are balanced by the centrifugal and gyroscopic forces on the airframe produced by the rotating motion.
……
Finally, it is important, particularly in this steady spin phase, in addition to using the correct control application and proper sequence of control application, to HOLD THIS APPLICATION UNTIL THE RECOVERIES OCCUR. In extreme cases, this may require a full turn or more with full down elevator deflection.”
Pretty clear to me.
Thread Starter
What's the bet that if you ask any current flying instructor in Australian flying schools the recovery technique they teach if a wing drops at the point of stall, invariably they will say "Don't use aileron but pick up the wing with rudder" and proceed to yaw (skid with excessive rudder) the aircraft to level the wings. I find it incredible that this myth persists of "pick up a dropped wing with rudder" rather than prevent further yaw with rudder.
I am a current flying instructor, running my own school, and we teach the concept of “stalled stick position” and recovery through AoA reduction as the primary control input. Judicious aileron / rudder input accompanying it. Or... let go the stick - Beggs-Mueller has a dog in this fight!
In order to minimise height loss, set the elevator control just forward of the SSP to be unstalled (but with close to maximum lift) and apply power - thrust reduces height loss as well as AoA.
We have little hope when CASA promote stall awareness by monitoring airspeed as the primary indicator... just check out their newly released poster on the topic. How about learning where SSP is and understanding that forward of that is your “manoeuvre zone”, aft of it is stalled, and that flap for low speed / high AoA manoeuvre is not your friend (SSP moves forward as flap extends, thereby reducing manoeuvre margins).
Working in this space will keep me (and my team) busy for the rest of our careers - unf*#king what the sausage factories, aided somewhat by CASA, have produced!
Funnily enough the best solution is, in fact, the simplest!
I respect the stated view that the Stalled Stick Position (SSP) concept is valid for a typical ab-initio training aircraft. However, the stick position at the stall actually varies with weight and configuration (flap setting). It is also not applicable to aircraft that have a moveable stabiliser (such as larger air transport types) where the rate of pitch is controlled by either or both the elevator and or the trimmed position of the stab. The SSP technique may be of value to simplify initial attempts at stall recovery for a student in a light trainer, but under the concept of “primacy” I’d suggest that it is not a technique that should be embedded in early learning.
Fly Safe
PJ88
Fly Safe
PJ88
What's the bet that if you ask any current flying instructor in Australian flying schools the recovery technique they teach if a wing drops at the point of stall, invariably they will say "Don't use aileron but pick up the wing with rudder" and proceed to yaw (skid with excessive rudder) the aircraft to level the wings. I find it incredible that this myth persists of "pick up a dropped wing with rudder" rather than prevent further yaw with rudder.
Pick up the wing is not the same as prevent further yaw. In practice picking the wing up leads to problems (in my experience) bringing people closer to nastier regimes of flight. It is not what should be taught. IMO