Incipient Spin Recovery

[fireflybob]

Centralise controls and then recover from resultant UP but what do you teach to do with the power?

Some teach to close the throttle but others teach to leave power set.

Thanks for any help.

[Genghis the Engineer]

The RAF teaches close the throttle.

I agree and do the same - it removes power induced torque from the system, which otherwise can be spin promoting.

G

[blind pew]

But closing the throttle adds torque to the equation...
Better to leave alone unless height is a problem and then gradually apply power after centralising the controls.
Centralising the controls normally stops an incipient spin developing further.
In gliding one of the most dangerous phases of flight is the final turn where too many pilots don't recognise the incipient spin developing...I always taught if anything feels strange or the aircraft is not responding how it should then put everything in the middle and start again...it is better to crash in control than out of control....even better is to understand the pitfalls and avoid them.

[ShyTorque]

I was RAF trained by CFS and used to instruct on SEP (Bulldog UAS QFI). I wasn't taught to operate the throttle at the incipient stage recovery. Fully developed, yes of course.

[mad_jock]

What ever it says to do in the POH for that aircraft type.

[fireflybob]

What ever it says to do in the POH for that aircraft type.

mad jock, unless you can find it there is no incipient spin recovery listed in the PA38 POH

[Big Pistons Forever]

An incipient spin is a stall where the aircraft was allowed to yaw. So the first step is to teach the importance of not letting the aircraft to yaw if it stalls. The incipient spin exercise then is introduced to teach the student to unstall the aircraft and control a yaw that has allready developed.

But it is still just a stall recovery. The airplane had to be actually in a spin before the spin recovery actions should be used. For virtually any flight school trainer that requires at least 180 degrees of rotation with pro spin controls held

[mad_jock]

Its an incipient stall recovery, rudder to stop further yaw, reduce AoA leave the power alone until after the AoA is reduced.

The term Incipient spin is a load of bollocks. The plane can't be in a spin unless its stalled. If you don't let it stall you won't be in a spin. So you fix it by doing a stall recovery which is in the manual.

[fireflybob]

So you fix it by doing a stall recovery which is in the manual.

Interestingly enough looking at my copy PA38 POH Stall Recovery is not listed (although 4.35 gives general information on the stall) but Spin Recovery is.

[mad_jock]

Its been years since i have been near one. Pretty sure the one i looked it did. Because it was a caa addition to the manual along with the 4 point harness stuff.

[glendalegoon]

dear mad jock

your words on the stall are right on.

U can't spin unless you are stalled, so don't stall.

this is the most important concept in the early stages of flying.

thanks mad

[nick14]

Speak to any aerobatic pilot and they will say spin recovery is better with power as the wash from the prop gives far more control effectiveness than torque promotes the spin. Has anyone seen a student apply full opposite rudder and reverse the spin direction at the incipient stage? I have seen it demonstrated by my aeros instructor, quite something.

Personally I feel you don't have time to mess with the power, centralise controls and see what attitude you come out at, if it's nose up add power and wait, nose down set idle, roll, pull (gently unless you have +6 to play with)

[18greens]

The term Incipient spin is a load of bollocks. The plane can't be in a spin unless its stalled. If you don't let it stall you won't be in a spin. So you fix it by doing a stall recovery which is in the manual.

Interesting. I may have missed the gist of this. If there's no incipient spin stage do we just go straight from flight to full spin?

As I recall the incipient stage isn't just a stall it's a stall with full rudder, rolling the ac onto its back followed by a sharp nose down and lots of rotation. Until the first full turn is complete the spin is considered incipient and will recover with centralised controls. Beyond the first turn full anti spin controls are required. Agreed if you don't want to spin don't stall. But I believe I believe in incipient spins. (Until someone disproves another thing I've believed forever)

Oh and if the firefly I've been aero batting has just flicked (again) when i was looping or pulling up or just plain old turning (like they do...) I wouldn't bother with power , unless more was available, a simple unload of the stick would work fine to recover. So to answer the op, leave the power alone, just unload ( unless the poh says otherwise)

[Genghis the Engineer]

Flight testers can argue for hours about how long the incipient spin lasts, but all agree that it exists.

From a flying training perspective however, it's probably until you know which way it's spinning. Before that, opposite rudder - well opposite to what? If you don't know, and possibly the aeroplane doesn't know, rudder inputs as per most POHs, may well create, not stop, a spin.

G

[djpil]

Speak to any aerobatic pilot and they will say spin recovery is better with power ...Not me, not generally. Not just the effects of slipstream and torque but also propeller gyroscopic moments which will be different depending on directions of rotation.

Australia's Civil Aviation Safety Authority's Flight Instructor Manual:

RECOVERY FROM A WING DROP AT THE STALL
“Use the standard recovery, i.e. simultaneous use of power and forward movement of the control column. In addition rudder must be used to prevent the nose of the aeroplane yawing into the direction of the lowered wing. The ailerons should be held neutral until control is regained, when the wings should be levelled.”

RECOVERY AT THE INCIPIENT SPIN STAGE
“….. before the spin develops fully you will be recovering by ensuring the throttle is closed and the controls are centralised followed by recovery from the ensuing unusual attitude.”

[CISTRS]

It's easier to do a recovery from an incipient spin, than to describe it.

For a glider pilot, in tight thermalling turns, the onset of the stall buffet can be countered by reducing back pressure on the stick, reducing AoA. If you are in balanced flight, (ball and yaw string in middle) there will be little or no tendency to drop a wing.
To achieve balanced flight in these conditions, you sometimes need to have what seems to be crossed controls - just fly the plane and don't focus on stick and rudder positions.

It's been many years since I have done this....

[mad_jock]

you see I don't think its an incipient spin if your stalled.

A spin only occurs when you are stalled and you don't control the yaw or botch the control of the yaw by applying to much.

An incipient spin is an incipient stall and if you deal with it as such you don't spin.

As soon as you dealing with a requirement to neutralise controls etc your in a spin and there is nothing incipient about it.

It will exists just like there is an incipient spiral dive.

Its when the plane is about to stall and is yawing and not being controlled. Or it is stalled and starting to yaw.

Doesn't really matter what its doing a stall recovery will sort it. If your not stalled you won't spin and it will turn into and spiral. So your actually incipient spin/incipient spiral dive and it depends on your actions what it turns into.

[djpil]

The USA FAA defines an incipient spin as the motion between entry and a fully developed spin. CASA describes a wing drop at the stall as an incipient spin entry in its pilot training syllabus. I see that the UK CAA Std Doc 10, Guidance for Instructors etc, requires knowledge of:
"signs of autorotation and an incipient spin"
"symptoms of a developed spin"
Seems that other authorities use the same definitions as the FAA.

[Tinstaafl]

I taught thusly:

If you can control heading with rudder ie ideally prevent heading change, but wing drop not worsening is ok too, no matter how much the wing drops, then it's an incipient spin & use max power (after reducing AoA) to reduce altitude loss.

If heading can't be controlled then use the type's spin recovery - usually something like:
power off,
centralise controls,
opposite rudder,
pitch towards the ground until until no longer stalled,
roll to the nearest horizon,
pitch to the sky,
add power once pitch level or above the horizon.

[Dan Winterland]

The RAF teaches close the throttle.

It's type specific. On the Chipmunk and Bulldog, the recovery was to centrralize the controls only. The Tucano, centralize and idle thrust. As the Tucano prop does 2000rpm in flight regardless of the throttle position, there are no gyroscopic force changes to worry about.

The RAF defined an incipient spin as buffet with undemanded roll, the combination of the two should warn you that you need to centralise. As the training was to teach pilots who would fly aircraft where this combination was a bad thing (Harrier, Jaguar, Buccaneer, Phantom Lightning and to a lesser extent the Tornado) this was good advice and the main emphasis in the training. Trainee pilots would get lots and lots of practice so that the recovery would be instinctive.

The RAF define the change from the incipint spin to the full spin as when the aerodynamic and inertial forces balance each other out. That sounded like a good explanation to me.

[BEagle]

Hi Dan, you foreign devil!

I found my old Spinning 2 notes - basically brace the control column and rudder central until the buffet / undemanded roll stops. If nose high, full throttle, if nose low, idle power. Then roll to nearest horizon, level wings and recover from the descent.

I didn't care much for the 'nose high / nose low' assessment, so I said 'if IAS changing rapidly, move throttle in opposite sense - otherwise leave it where it is'.

During CFS time, a colleague and I did a 'giveback' session of Spinning 2 - his demo. of 'full spin from manoeuvre' was interesting - pull into the vertical from about 120KIAS, apply full pro-spin and close the throttle....:uhoh: The poor little aeroplane went nuts as I sat there playing Bloggs and he tried to sort out the recovery.....:eek:

[ShyTorque]

Dan, Beagle, thanks - that confirms my reply about RAF training.

One thing to remember is that an incipient spin can occur in any attitude, such as during aerobatics. Talk of heading change and wing drop is more relevant to straight and level stall/spin entry.

Civilian students, at least at PPL level, and probably at CPL level, are unlikely to see the former unless they are being taught beyond the normal syllabus.

The Bulldog "spin off manoeuvre" was demonstrated to UAS students. IIRC, this was done by applying pro spin control during a loop, at least, that is what I remember doing.

I used to enjoy this part of the syllabus, most students didn't... :E

[Arm out the window]

RAAF training for incipient spin in the PC-9 (defined as two turns from application of pro-spin controls as I recall, and probably rightly so - the first couple were flopping about until the aircraft established itself in a 'proper' nose down spin) called for throttle idle and controls central, whereupon it would quickly recover.

Fully developed spin recovery was confirm idle, identify direction of spin (turn needle), apply and hold full opposite rudder with control column central until spin stopped, centralise rudder and recover from the dive.

Incipient spin training is useful in my opinion so that when we stuff something up (eg mishandled aeros), feel buffet and notice the onset of autorotation, the instinct is there to close throttle and centralise. Then if it develops into something more fully developed, the flight manual recovery for the aircraft in question is the next port of call.

So - incipient spin - close to stall, buffet, uncommanded roll - go for the incipient spin recovery.

[mad_jock]

I think we need to define what level of pilot we are teaching this to.

PPL

Aero

CPL

Instrumet

What flavour.

PLL I would teach them not to get near it and to recover as per normal stall recovery.

What you aero boys/girls do I have no idea.

[Genghis the Engineer]

It's type specific. On the Chipmunk and Bulldog, the recovery was to centrralize the controls only. The Tucano, centralize and idle thrust. As the Tucano prop does 2000rpm in flight regardless of the throttle position, there are no gyroscopic force changes to worry about.

The RAF defined an incipient spin as buffet with undemanded roll, the combination of the two should warn you that you need to centralise. As the training was to teach pilots who would fly aircraft where this combination was a bad thing (Harrier, Jaguar, Buccaneer, Phantom Lightning and to a lesser extent the Tornado) this was good advice and the main emphasis in the training. Trainee pilots would get lots and lots of practice so that the recovery would be instinctive.

The RAF define the change from the incipint spin to the full spin as when the aerodynamic and inertial forces balance each other out. That sounded like a good explanation to me.

Thanks for that correction - most of my military LOC work was with the Tucano, which would explain my slightly incomplete recollection.

Darrol Stinton, who was an instructor at ETPS and wrote a few rather good books on aircraft design and flight testing, used a similar definition for incipient then fully developed spin, but reckoned that was normally about the first 6 turns. By that definition (which holds some reasonable water when you look at instrumentation data from a few spinning-instrumented research aeroplanes) most of us have never seen a fully developed spin.

G

[ShyTorque]

Mad Jock, surely an incipient spin is the same, irrespective of who is at the controls.

The correct teaching should surely be to recognise and efficiently recover from any attitude, rather than merely to complete a set piece manoeuvre from an ideal straight and level entry because a syllabus requires a box to be ticked. Pilots don't generally enter an incipient spin from S&L, but from a botched manoeuvre.

The UK PPL syllabus isn't the same since spinning was no longer required, pilots still make handling errors such as low speed/ too high a rate of bank on the finals turn and still need to know what to do about them.

[mad_jock]

It is and it isn't.

For PPL level the deal is to stop them getting into that position anyway.

Most PPL and CPL's these days won't have a clue what you guys are on about anyway.

FI's will have had to demonstrate one spin in their test but that's about it.

[Genghis the Engineer]

I agree MJ, and worse I gather that under EASA the spin recovery has now been quietly removed from the skill test.

I think that removing spinning from the PPL syllabus was sensible, but complete removal is not. I think, myself, that it should be in the CPL syllabus.

G

[mad_jock]

Well removing it from the FIC is a bit daft cause those buggers will get you into unusual attitudes in a blink of an eye.

Mind you I never anyone succeed getting me into a spin. Close a few times

[Big Pistons Forever]

I think the most practical deliniation between an incipient spin and a spin is

Incipient spin. Stall recovery actions will allow control to be regained. That is stick forward, full power, control the yaw with rudder

Spin. A stall recovery will not work because the rotation must be stopped before forward stick can be applied and the power must be reduced to idle.

For all common trainers you need to get well into the second turn before simply applying forward stick will not effect a recovery.

Canada does not have spins on the flight test but the instructor is required to demonstrate one prior to solo. I always do one just prior to going to the circuit and do it by setting up a too slow skidding base to final turn scenario (at altitude in the practice area of course)

Outside of aerobatic training the spin is not a manoever, it is the consequence of screwing up, badly. I strongly feel that if it is going to be demonstrated as part of PPL /CPL/type training than it should be presented not as "today we are going to learn how to do a spin" but rather "this is what will happen if you allow the aircraft to inadvertently stall (BAD !) and then don't control any yaw that develops (WORSE !).

The best way to do this is to present the student with the common stall/spin scenarios. Success is not recovering from the spin it is recognizing and avoiding entering the incipient spin in the first place.

[G-F0RC3]

I wasn't required to do spin recovery during my PPL training (a couple of years ago now). However, I made a point of learning what control manipulations would be required to recover from one in the aircraft I was flying in case I needed them. It just seems like common sense to learn these in my opinion. :)

[Speed Twelve]

Current UK military training for the Tutor is still as Beags, Dan etc have mentioned above. The symptom of an incipient spin is undemanded roll, centralise control column and rudder, leave the throttle, then recover from the resulting UP as required.

There's only the one drill, keeps it simple. Works every time. I agree that in the average Cessna, Piper etc you'd have to be pretty ham-fisted to end-up with undemanded roll in normal civilian flying. I agree the Firefly M used to flick like a good 'un if you pulled through the heavy buffet.

Are visual UP recoveries taught on the PPL or CPL course out of interest?

The Tutor Standard Stall Recovery incidentally doesn't involve the use of rudder either, other than to prevent yaw when selecting full power during the recovery itself and to balance if using aileron to level the wings after the buffet stops.

[Genghis the Engineer]

Are visual UP recoveries taught on the PPL or CPL course out of interest?

Yes, it's called "recovery from unusual attitudes".

This is an American site but covers the UK teaching fairly well in IMC, pretty obviously in VMC it's the same using the visual horizon as reference.

Technique: Turns around a point - Flight Training (http://flighttraining.aopa.org/magazine/2011/October/technique.html)

G

[Speed Twelve]

Cheers Genghis, but that article covers UP recovery on instruments, standard for all instrument-rated pilots as you know.

I was wondering if civilian pilots were taught Unusual Position recovery using visual attitude techniques i.e. to cover loss of control in VMC, turbulence upset, disorientation etc. Spiral descent recovery I seem to remember being in the syllabus, it's a lonnnnnng time since I've trained civilian students.

[Genghis the Engineer]

Oh yes, sorry.

The bulk of training at PPL level is stall avoidance and recovery. Spiral dive recovery is there, but much more emphasised in the NPPL(M) as it's a significant issue particularly in flexwings which can lock into the SD unless actively recovered, than in any "heavier" licence.

UA recovery is in the CPL - the VFR qualification - flown under the hood both full and partial panel as part of the IF component of that.

G

[Speed Twelve]

Thanks Genghis.

Is the issue with flexwings due to the wing locking into a certain position due to aero loads and therefore having to be manhandled into a recovery position?

[Genghis the Engineer]

Good question. I *think* it's because the very high directional stability of the highly swept delta wing, which makes it effectively impossible to spin, allows the wing, once a turn has developed, to continuously weathercock into the sideslip component of the unbalanced turn, and then the fact of the tilted lift vector, causes the accelerating rate of descent. Probably.

Recovery is easy, reacting against the trike, just place the control bar parallel with the visual horizon (well, easy to understand, but can require quite a lot of physical effort). But without that, the aircraft just maintains an accelerating and tightening turn, which presumably would result in either structural failure or ground impact.

I have played some years ago with significant rolling inputs at the point of stall in a flexwing to see what would happen. The rolling departure feels for maybe a quarter of a turn rather like a 3-axis incipient spin, but rapidly speed builds and it has clearly become a spiral dive, which then requires the standard recovery.

G

[Speed Twelve]

Interesting. Anything that requires you to push away to pitch up is a black art to me!

[dobbin1]

The EASA syllabus defines incipient spin as a stall with wing drop :-

(xiv) Exercise 11: Spin avoidance:
(A) safety checks;
(B) stalling and recovery at the incipient spin stage (stall with excessive wing drop, about 45°);
(C) instructor induced distractions during the stall.


I do most of my training in DA20 A1 Katanas, where it is quite easy to provoke a wing drop with a small nudge on the rudder, especially when there is some power applied. The recovery is standard stall recovery, full power, stick centrally forward and enough rudder to prevent the nose yawing toward the ground. Too much rudder and the wing drop will go the other way. I generally only do this once with my students, just until I can feel them adding the top rudder to stop the yaw when the wing drops. I have never got into a full spin doing this.

Some students want to experience full spins. If so, I teach them spin recoveries in our Firefly where we can wear parachutes and have a jettisonable canopy. I have spun the Katana alone wearing a parachute but it was very uncomfortable.

[nick14]

Surely we would always teach to lead with lowering the angle of attack first not power?

[Genghis the Engineer]

Interesting. Anything that requires you to push away to pitch up is a black art to me!

They are fascinating things, but undeniably very "different" to conventional aeroplanes - to the point that I gather pilots with significant time on conventional aeroplanes usually take longer to solo one that an ab-inition student. Everything is different - push right to roll left in flight, and push right to turn left on the nosewheel steering, plus a foot throttle.

Once learned however, my experience is that it's like riding a bicycle - in that I find going from a conventional aeroplane to a flexwing is much like going from a car to a bicycle - so different I don't get confused any more.

Worth a go if you ever fancy a bit of novelty and excitement in your life - just do it on a nice warm day :8

G

[dobbin1]

nick14
Surely we would always teach to lead with lowering the angle of attack first not power?


Of course. I should have said stick centrally forward, full power....

[fireflybob]

Surely we would always teach to lead with lowering the angle of attack first not power?

nick14, I agree with the point you are making but would prefer the phrase "move the control column centrally forward until the buffet stops (or, as I prefer, until the stall identification ceases)".

"Lowering the angle of attack" might be confused with "Lower the nose" and whilst it tells the student what to do, it doesn't tell him/her how to do it.

As I was the OP on this thread I thank all who have contributed to an interesting debate which is how we learn.

[Big Pistons Forever]

I tell my PPL students to "lower the nose".

Theory "Reduce the AOA" is for the class room.

Practical actions "Lower the nose" is for in the airplane instruction.

[CISTRS]

For PPL students - agree.

For more advanced or more adventurous pilots, I really prefer to say "reduce back pressure on the controls". This directly affects the angle of attack, gives tactile feedback (buffet stops) and will unstall the wing.
In a high speed stall or tight turn, this may not mean the same as "lower the nose".
Incipient spins usually arise from unbalanced turns rather than low airspeed alone.

[LOMCEVAK]

Can I add another aspect to consider when defining an 'incipient spin'.

Let's first consider what defines a 'fully developed' spin. This is one in which the mean axis about which the aircraft is rotating is vertical. The aircraft will have pitch, roll and yaw rates but there will be an earth referenced axis about which the overall rotation occurs. Any consideration of the balance of inertial and aerodynamic moments relates to whether the spin is oscillatory or non-oscillatory. For example, if the moments are not balanced but the rotational axis is vertical then the aircraft will be in an oscillatory, fully developed spin.

Immediately before the control inputs that cause an aircraft to spin are made, it will have a flight path which inevitably is not vertically down as will be the case in a fully developed spin (you can flick-roll on a down vertical but airspeed will generally be too high to enter a spin). Therefore, there is another phase of the manoeuvre between entry and the fully developed spin, and this is what is generally considered in my world to be the incipient spin. This may last anywhere between about 1.5 and 4 turns from a level entry but could well be as high as 6 turns from a manoeuvre. It very type specific and also varies according to the aircraft's flightpath and power setting at entry.

In my opinion, what you do with the power in the recovery from an incipient spin needs to be type specific because the effects of propwash, torque and gyroscopic moments vary from type to type, and direction of spin along with being erect or inverted may require different optimal power settings. And let's not forget that jets spin also! However, for training simplicity and safety it is best if the recovery from the initial stage of an inadvertent spin is the same as that from an unusual attitude recovery and therefore some degree of compromise may be necessary to achieve this so long as recovery from a spin is not prejudiced.

I fly and spin one type that when centralising the controls during an incipient spin, as defined above, often does not result in recovery. This is the Harvard in a right, idle power spin. Any more than 1/2 turn and it requires at least 1/2opposite rudder as well as neutral or forward elevator to recover. I accept that we do not attempt this recovery power on, in deference to the age of the aircraft, and so I cannot say whether or not that would improve recovery characteristics.

[Bizdottest]

ICAO has an initiative to introduce LoC/upset recovery to all training courses from CPL onwards; EASA has a working group looking at that issue.
Personally I would teach scenario based LoC/upset from Ex 4 PPL (the spiral dive) and get away from the traditional concentration on academic stalling exercises which seem to based on the skill test requirement.
'Recognition and recovery' is the aim not pretty exercise sets.

[nick14]

The Working Group's main objective is to design a UPRT programme for CPL and type and class rating training, however this module is 95% avoidance and prevention, hence Upset Prevention and Recovery Training.

I'm not sure whether they will add in spinning at all.