Picking up a stalled wing with full rudder no aileron.

[Dan Winterland]

Genghis explained it technically. Captainsmiffy explained it in pilotspeak. BEagle has applied the correct emphasis. No further explanations are required.

[formationdriver]

Spin exit: simultaneous power off, neutral ailerons, full rudder toward the wing in the blue, or gray (foot in the sky) + forward stick. When the sight picture is 'normal," i.e. the world stops spinning on the other side of the windscreen, rudder back to neutral, gentle pull to bring the nose up to the horizon (not too roughly or the plane will re-stall) and power as needed. Works just fine in everything form C-152 to CAP10, Pitts S2B, SF-260, 8KCAB,T-6, PT-17 and Extra 300. Accueil | CAPTENS

[Level Attitude]

the world stops spinning on the other side of the windscreen, rudder back to neutral, gentle pull to bring the nose up to the horizon

For completeness I think you may want to add in an extra step otherwise you may well often be practising spiral dive recoveries.

[Genghis the Engineer]

So long as you don't get the rate of forward travel wrong, use that drill in.some Jodels which require back stick, nor in some microlights which use a controls central recovery as the powerful cruciform rudder may push you into a spin in the opposite direction.

I'm a fan of standard stall recoveries, but in my experience - which includes running the spinning trials on several new types - spin recoveries are often type specific and the POH matters.

G

[BEagle]

There is NO SUCH THING as a 'Standard' spin recovery.

Although AoA and yaw must be reduced, the sequence and timing of control movement is indeed type-specific.

[Centaurus]

There is NO SUCH THING as a 'Standard' spin recovery.

Yes and no. But you have to start somewhere and as such the "standard" spin recovery was taught to RAF trainee pilots (and other Commonwealth military services) before the start of WW2 and continued. A glance through many of the Pilots Notes published by the RAF for example and used by Australian, Canadian, and New Zealand Air Forces in those times, reveals variations of the theme.

The single seat Vampire PN makes no mention of how to recover from a spin.
The DH Mosquito PN says "Intentional spinning is not permitted. An incipient spin should be checked immediately by normal recovery action".
Sea Fury. No mentioned of spinning.

Auster PN. Several paragraphs on spinning including the statement for recovery : "Apply full opposite rudder. Pause at least one second. Move the stick progressively forward until rotation ceases. Centralise the controls immediately. Pull out of resultant dive".

Hawker Hurricane. Spinning of Mk.2D and Mk 4 aircraft I prohibited at all times. On Mk 2A, Band C aircraft, spinning is prohibited when carrying 90 gallon drop tanks, bombs or RP. Recovery is normal but the loss of height involved in recovery is very great. Recovery is to be initiated before two turns are completed.

Mustang. There are several paragraphs on spinning. The opening paragraph states: "Practice spins are not to be started below 12,000 feet and the engine is to be throttled back before starting the spin. Recovery action is to be taken after not more than two turns. The average loss in height in turns left or right and in recovery is about 3000- 3500 feet"

The rest of the paragraphs on Mustang spinning is positively frightening such as the advice that if a power-on spin occurs as many as five or six turns may be made after recovery action and 9000-10,000 feet lost.

PS Dear Beagle. No real need to "Shout" in your Post No 25, old chap..

[Genghis the Engineer]

I rather approve of BEAGLE shouting. The desire for a universal spin recovery, far too often translates into people believing it's real. Whilst the differences can be small and subtle - they matter.

Taking one example already mentioned, when I tested the the Auster 5L for LAA when the type moved from CofA to PtF, I checked the "SSR" of immediate forward stick as well as the POH version. The POH version is fine, but immediate forward stick caused substantial negative G. Fine for a Test Pilot in a hard helmet, specially tightened straps and ready for anything - but somebody in an inadvertent spin? Similarly, when I ran the X'Air spinning trial, we showed that the SSR required identification of the spin direction by a pilot, which they weren't trained to do, and also the powerful rudder could kick the aeroplane into a spin in the opposite direction. Hence the controls central recovery, common on many microlights including the X'Air, Thruster, SkyRanger...

So, I am shouting alongside BEagle I'm afraid.

G

[212man]

The reason for not using aileron is exactly the same - any use of aileron will cause some sideslip

I was under the impression that the use of aileron will move the stalled section of the wing outboard, as the AoA is increased.

[Genghis the Engineer]

Can't say that I have ever seen that anywhere I would consider authoritative.

G

[212man]

My recollection came from UAS days, but some discussion on it here (NZ CAA website): https://www.caa.govt.nz/fig/advanced...-stalling.html

By using aileron to stop the roll (a natural tendency), the mean angle of attack increases on the down-going wing. The lift continues to decrease with an increase in angle of attack (past the critical angle), while the drag continues to increase rapidly with any small increase in angle of attack. Show the effect of aileron on the CL and CD curves on the graph.

The use of aileron adversely affects the roll and favours autorotation. This is the reason for maintaining ailerons neutral in the initial stall recovery.

[Genghis the Engineer]

That says roughly what I had. Nothing about changing alpha_max. Also not really authoritative regardless.

G

[fireflybob]

So we move the stick forward and simultaneously (UK, EASAland, Australia) or just after (FAAland) apply full power.

Genghis, nice post thanks but I was under the impression that EASAland was now stick (centrally forward) first and then select full power rather than simultaneous?

[Genghis the Engineer]

If they have, the docs have passed me by. Can you provide a reference?

Cheers,

G

[sapperkenno]

any use of aileron will cause some sideslip

My brain is starting to hurt a little now, but would co-ordinated rudder not negate/minimise this? Or are we saying that rolling an aircraft creates sideslip..? Or that an aircraft at any bank angle (even if co-ordinated) is slipping? If so, how? Not trying to be flippant, but just increase my level of understanding! Thanks in advance for any answers.

I also seem to recall an EASA/CAA document doing the rounds a couple of years ago re: reducing AoA, then increasing power, as opposed to "powering out". Will try find reference.

[Genghis the Engineer]

Yes - every time we fly a co-ordinated turn, we are using the rudder to remove sideslip created by aileron deflection.

I certainlyremember the documents slating powering out of the stall, but I don't recall their promoting a switch to the FAA stall recovery.

Relevant...
http://aerosociety.com/News/Publicat...ght-aeroplanes

G

[Centaurus]

For years I thought the idea of applying power at the same time as lowering the nose during stall recovery was to give immediate increase in slipstream over the various lifting surface and thus give more lift - thereby recovering from the stall. Prop aircraft only, of course. Have I got it wrong over all these years?

One way or another the aim is to recover from a stall. Lower the angle of attack (stick forward) and power simultaneously does just that. Jets are different. Increase thrust while simultaneously lowering the nose a few degrees to the horizon or just below, should increases speed hopefully and thus recovery from a stall should occur.

High altitude stall recovery is a bit different. You need to count on losing 3-4000 feet while deliberately picking up to a safe manoeuvering speed. Important to keep the aircraft accelerating downhill in this case to avoid secondary stall symptoms caused by nose wanting to rise with increasing IAS.

The Boeing 737 FCTM gives a good hint on defining "safe speed" before level flight is started. Vref 40 plus 100 knots. Typically around 210-230 knots IAS before levelling out or even attain severe turbulence speed before attempting to level out if the cause of the problem in the first place was severe turbulence penetration followed by an upset in IMC

[Genghis the Engineer]

For years I thought the idea of applying power at the same time as lowering the nose during stall recovery was to give immediate increase in slipstream over the various lifting surface and thus give more lift - thereby recovering from the stall. Prop aircraft only, of course. Have I got it wrong over all these years?

In my opinion, yes. More thrust is almost entirely about putting more energy into the system to reduce height loss.

Jets are different. Increase thrust while simultaneously lowering the nose a few degrees to the horizon or just below, should increases speed hopefully and thus recovery from a stall should occur.

In my opinion, that makes jets the same.

When we compared notes at the SETP symposium in Madrid 3 years ago between the GA researchers who wrote the paper I linked, and the joint Boeing / Airbus team presenting on large aircraft stalling - it seemed to me that the only real differences were of numbers - big jets take longer to do everything and lose far more altitude, but the handling and reasons for doing things really don't change.

G

[PDR1]

Originally Posted by Genghis the Engineer

In my opinion, that makes jets the same.

Except that you may not wish to "unsettle" a jet engine with a throttle movement once in a spin. If the engine keeps running with the strange flow conditions it's more likely to continue running if left stable, and far more likely to flame out if accelerating or decelerating.

PDR

[Genghis the Engineer]

That's a spin, not a stall and stall recovery. In my opinion, we should probably not jump back and forth between them quite so much in the same discussion? Whilst related, they aren't the same topic, and I certainly wasn't referring to the developed spin when I said that.

G

[Dan Winterland]

And the Hamster wheel turns full circle! It seems the notion of the "Standard Spin Recovery" reappears regularly on this forum every two years. There was one once , as someone points out. This is from WW2, when everything from instrument panels, checklists and recovery drills were standard. And in the wartime days of needing flexibility between types, it worked well. It was the introduction of the Chipmunk, for which the standard spin recovery didn't work so well, killing a few people (less acceptable in peacetime) that led to an adaptation. And it turned out that the standard didn't work for many other aircraft as well. The good advice is to apply the recovery for your type as described in the POH. And there are some really large variations. For example, the Cirrus SR22 requires you to immediately deploy the ballistic recovery system and the Jaguar required you to centralise the controls, if not recovered by 10,000ft - eject! there are so many factors, aerodynamic, power and inertial considerations that you really need to be aware of your type's recovery technique.

And now, there's no standard stall recovery. Experience has shown that low slung engines coupled with nose up stab trim impedes the recovery in modern jet transports, so we now have type specific recoveries. In the A320, we lower the nose, level the wings, ensure speed-brakes are retracted, select Flap one if clean, and only when the aircraft is out of the stall, apply power. This is fresh in my memory as I was practicing them in the sim 2 days ago. And it is very hard to forget 30 years of using a previous drill and applying power immediately.