Standard Spin Recovery

[mad_jock]

"Darwin award" technique

[kluge]

So the concise collective learning of all of this is:

1. There are no standard recovery techniques. Therefore;
2. RTFFM (aka POH) per the aircraft you are responsible for, understand what it ALL means and be self disciplined (esp CG pos and/or turning final - this is when "Brown Bread Club" membership is at its greatest).
3. Beggs Mueller as a backup for intentional and unintentional upright, inverted and flat (upright or inverted) spins. Presumes you have sufficient recovery height.
4. When all else fails jump (parachute and sufficient height required) or BRS or MB options if fitted.

If all that fails then:

5. "Always look on the bright side of life" and enjoy the ride.


Point 2 seems to be the hardest to learn.

[tigerbatics]

Of course there is a 'standard spin recovery'.

That is not to say that it is a 'universal' spin recovery. It was taught to me back in the 70s and was clearly derived from Service experience with Chipmunks. It provided the standard from which type specific changes could be made. Without a standard it is too easy to view each type as wholly different rather than as variations on the same theme. This, I think, makes more difficult a proper appreciation of the nature of the spin.

It is also worth pointing out that the POH does not always give the best or most efficient spin techniques, either entry or exit, at least where aerobatic aeroplanes are concerned.

When Eric Muller came up with his emergency recovery technique it created some controversy over here and seems to have been appropriated by Beggs in the States and taught as a new technique by several instructors over there. I have a copy of Beggs booklet and the outline of the 'spin course'. From this and from other books written in the States the position seems clear that it was being presented as appropriate for use in the recovery of all types of spin in most types of aeroplane. I believe some instructors teach it as, shall we say a standard spin recovery, for aerobatic machines.

This is not what Eric Muller intended at all. I knew him quite well and we had long discussions on this and most other aerobatic subjects over a period of some years. The so-called 'emergency recovery' derived from his own recovery technique in aerobatic machines, which was;
1) close throttle
2) opposite rudder
3) full back stick
4) full in-spin aileron
With all items done AT THE SAME TIME. That is, no pause between any control applications.

It was when he noted that if he let go of the stick in the spin (erect) it went to the full back in-spin position anyway and without his specific control movement that he started to think about a different emergency technique.

Now this is the point. It should not be seen as a specific spin recovery method in it's own right but rather as one application of the method for recovering control during aerobatic practice when the machine falls out of control. By 'out of control' I mean when the aeroplane is doing something other than that which the pilot thought, or hoped, he was telling it to do. At that point the pilot should stop telling it anything at all, because clearly the wrong message is being given. Hence the advice to cut the power and let go of everything; let the machine sort itself out then resume control after identifying what the aeroplane is doing. Chasing the machine around with a series of inappropriate control inputs has caused a large number of accidents over the years.

The 'emergency recovery' touted by some instructors in the States is very plainly NOT a universal solution and does not provide the most efficient or attractive spin recovery when the aeroplane is still firmly in control and the spin intentional. Pitts pilots, for example, will find recovery from a flat spin much more controllable and quicker if a totally different techique is used in which the power is left FULL ON. So will those in Extras.

[Dan Winterland]

Errrrr......if it's not a universal spin recovery, then how can it be standard?

The "standard" stall recovery from the PPL syllabus is universal. Using the phrase "standard" when talking about a spin recovery is misleading. Your example of the recovery technique developed for the Chipmunk isn't a good one as the Chipmunk ended up with a different technique to many other aircraft after several accidents where it didn't recover when following use of a 'more typical' recovery technique.

[tigerbatics]

The words 'standard' and 'universal' do not mean the same thing. There is no need for a standard to be universally applicable in order to amount to a proper standard.

A standard technique may form the norm,or baseline,or point of reference, or default situation, call it what you will. In order to constitute a standard it needs to be of sufficient relevance to make useful a comparison of other techniques with that standard.

This is, it seems to me, what the normal spin recovery taught as non type specific spin recovery under the name of 'standard spin recovery' was all about.

My reference to the Chipmunk holds I think. There is little variation in the spin recovery from the 'standard' in the Chipmunk. A very great deal of PPL training in the 70s, and maybe today,derives from service practice. Trying to pick up a wing drop in the stall with aileron inevitably results in the application of outspin aileron should the aeroplane enter a spin. This has the prdictable result of causing the aeroplane to enter a flatter spin with all that this entails. The Chipmunk is not and never was unusual in that respect.

[cessnarepairman]

Spin Recovery

It is an urban myth about the Chippy spin recovery, you should read De Havilland TNS 142 from 1960.

I would doubt if a light aircraft has ever been put through an extensive spin trials, all because one in Australia failed to recover.

[lady in red]

Well I doubt that I am the only person to have experienced trying to demonstrate spinning and having the aircraft NOT recover despite using the "standard spin recovery" method. Aircraft in question was a C150 aerobat and it did not respond at all to the usual method. In the end I had to use in-spin aileron to recover having lost well in excess of 3000 feet. Bottomed out at just 1100 feet.
Once safely back on the ground, the aircraft was stripped down by the engineers who found nothing wrong, however, the CAA test pilots flew it and grounded it and when it was examined properly it turned out to have a bent wing which was several degrees out of true.
The lesson I learnt was never to trust the paperwork of engineers and a flight school you do not know (I was a guest FIC instructor there).

[Dan Winterland]

If you compare the Chipmunk spin recovery with one of the more usual trainiers, the C152 you will notice a difference. The C152 POH states " Apply and hold full rudder opposite to the direction of rotation. Just after the rudder reaches the stop move the control wheel briskly forward far enough to break the stall". Compare this with the RAF Chipmunk AP101B (Pilot's notes) "Apply and maintain full rudder opposite to the direction of yaw. After a brief pause, move the control column frimly and progressively forward until the spin stops".

They are almost the same, but there are subtle differences. The C152 wheel movement is almost instantaneous (as backed up by the placard which doesn't mention "just after"). Whereas the Chipmunk control column movement needs a pause. The RAF used to stipulate 2 seconds to allow the rudder to take effectiveness. Those two seconds seem like a long time when you are spinning earthwards and I have seen plenty of students either forget the pause or counts 2 "elephants" very rapidly. The recovery does take longer in this case. Also, the C152 'brisk movement' is different to the Chipmunk 'progressive movement'.

The C152 is probably 'more standard' than most. The Chipmunk is different. It's recovery was developed after a failure to recover using a 'more standard' technique. And when the Bulldog entered RAF service, it's spin characteristics were different to the Beagle Pup it was developed from. After two aircraft were lost spinning , research showed that the larger canopy was blanking the rudder. So a different technique was developed where the contol column was moved rapidly forward resulting in an almost negative g bunt.

So, there is no standard recovery where these three types are involved.



Cessena repair man. I had a look at TNS 142. It refers to the rear bulkhead corrosion problem, so I'm not sure what your point is. And I don't know what the myths regarding the Chipmunk are. When I flew them in the RAF, we used facts - and the manuals!



LIR: I too have nearly lost an aircraft due to a wing being out of incidence limits. In this case, it entered an inverted spin from an erect spin. It looked like an erect spin, but had an attitude close to the vertical and a rotation rate much higher than the normal. The turn and slip was telling us it was an inverted spin, but we took a while to believe it and effect a recovery. In this case, we had the Martin Baker alternative and were close to using it. I'm not fond of spinning without a parachute.

[cessnarepairman]

Ive rechecked that, I'm always one to admit I'm wrong, but not in this case. TNS CT (C1)142 published 17-10-60 "The Chipmunk Spin- The Facts" there is a copy in the latest TNS manual from DH support.

[tigerbatics]

DW, what you describe as the 'Chipmunk' recovery is exactly what I was taught in the early 70s as a non type specific 'standard' in a Beagle Pup.

From your description it is also perfectly ok for a C150. However I have never flown a Cessna so have no personal experience. Variation in the desired rate of control application does not seem a sufficient reason to deny the existence of a 'standard spin recovery' any more than the fact that some types may require a slightly varying technique.

I stress the point previously made that a 'standard' is just that and the very idea of a standard involves the possibility of departures from that 'standard'. That is what the word means. This is why it is not to be confused with 'universal' and the method was not called a 'universal spin recovery'.

[Dan Winterland]

CRM - the list I found was the New Zealand CAA's list of Chipmunk TNSs. 142 refers to the rear bulkhead. I see that your list (Is that the UK CAA list?) refers to spinning, but I couldn't find a link to the text. Do you have one?




Tigerbatics - I can't agree with you. I accept there is a sequence of events which are carried out to recover a spin, but their application is different enough to render the notion of a standard recovery for all types misleading. I have instructed spinning in C152 and the Chipmunk. Their recoveries are different. I have also instructed spinning in several other types and spun many more - and again, there were differences.

The danger of entereing a full spin unintentionally is minimal. Those entereing a full spin intentionally need to be familiar with that type's recovery technique. Use of the wrong technique can lead to a delayed recovery - or some other problem. Use of the Chipmunk technique in the Bulldog will not lead to an effieicent recovery.

If you want to teach a recovery technique which will work in an emergency for most types such as Australia's CASA mentions in it's free to download instructor manual http://www.casa.gov.au/aoc/training/guides/fim.htm then do so but referring to it as standard may lead to a pilot thinking it's OK to use if he goes spinning intentionally.

[Dan Winterland]

And while I'm thinking about it, here are some more less than 'standard' spin recoveries.

Robin R2160. Apply oppsite rudder. Move control colum fully rearwards.

Cirrus SR2: Immediately deploy balistic recovery system.

Hunter: Stick back, apply in spin aileron.

Jaguar: Release all controls. If not recovered by 10,000', eject.

[kluge]

Hhmm - I was taught Mueller/Beggs for the R2160.
In hindsight this was probably to maintain procedural consistency for Pitts flying.
Whilst Mueller/Beggs worked for both a/c I agree with you that there is not a standard recovery technique in the true sense of the word.

I dimly recall reading about the large ventral fin on the R2160 as having something to do with spin recovery. Do you know ?

Your Jaguar comments are interesting. Tell more please.

[tigerbatics]

Kluge, see my comments above about the Muller/Beggs method. This is not a proper 'stand alone' spin recovery technique and was never intended to be. You will see, if you look above, that the Robin technique DW mentions is very close to that which Eric Muller used himself.

The Muller/Beggs emergency recovery should not, in my view, have been taught to you as a method of normal spin recovery in the Robin. The same is true of the Pitts so no question of consistency arises.

[kluge]

Well, it works consistently and reliably for both incipient and fully developed spins in R2160 and Pitts S2A, S2S and S2B aircraft.

"In some aircraft that spin readily upright and inverted—such as Pitts- and Christen Eagle-type high-performance aerobatic aircraft—an alternative spin-recovery technique may effect recovery as well, namely: Power off, Hands off the stick/yoke, Rudder full opposite to the spin (or more simply "push the rudder pedal that is hardest to push") and held (aka the Mueller/Beggs technique). An advantage of the Mueller/Beggs technique is that no knowledge of whether the spin is erect or inverted is required during what can be a very stressful and disorientating time. Even though this method does work in a specific subset of spin-approved airplanes, the NASA Standard/PARE procedure will also be effective, but care must be taken to ensure the spin does not simply cross from positive to negative or vice versa. The converse, however, may not be true at all—many cases exist where Beggs/Mueller fails to recover the airplane from the spin, but NASA Standard/PARE will terminate the spin. Before spinning any aircraft the flight manual should be consulted to establish if the particular type has any specific spin recovery techniques that differ from standard practice."

Above taken from wikipedia....ok ok.... but i think it fleshes out the point which is that there is no standard recovery technique. The last sentence relates to point 2 in my original post on this thread.

[kluge]

I'll edit my original list with:

So the concise collective learning of all of this is:

1. There are no standard recovery techniques. Therefore;
2. RTFFM (aka POH) per the aircraft you are responsible for, understand what it ALL means and be self disciplined (esp CG pos and/or turning final - this is when "Brown Bread Club" membership is at its greatest).
3. Beggs Mueller as a backup for intentional and unintentional upright, inverted and flat (upright or inverted) spins. Presumes you have sufficient recovery height.
4. Try PARE to terminate the spin.
5. When all else fails jump (parachute and sufficient height required) or BRS or MB options if fitted.

If all that fails then:

6. "Always look on the bright side of life" and enjoy the ride.

[homeguard]

to be or not to be, that is the question ......

Following this considered and articulate debate, it is no wonder that such a thing as a 'standard stall/spin recovery' was devised. From this debate it is not possible to summarise a consensus, each maintains their original stance. Outside of this forum there are more variations, on the theme, from many respected aerobatic and test pilots that I have read or consulted.

A dilemna for any insructor, teaching the PPL, is how far does one take it teaching specifically with regard to the particular machine flown and conversely to what extent should the training provide for a broader platform. With regard to aerobatics it is simple; the correct method is that promulgated for the particular aircraft. However, not even that provides for a consensus for many internationally proven aerobatics pilots have devised their own methods that they swear by and they are willing to give much time to persuading others of the reasons and benefits.

The specific methods can be achieved easily within controlled environments, such as the military but not only, when normally a single type will be flown at any one time. The dilemna remains elsewhere. Within the normal club environment and following qualification the pilot will often be low houred and flying perhaps 12 to 25 hours per year. The actual number of fights may be less. This same pilot will perhaps fly a number of different types during a year. Many of these types cannot be deliberately spun to provide any further training anyway. It is this pilot that needs some special consideration.

The 'standard', stall and spin recovery techniques, devised for these people, was never said to be an all embracing fix nor a replacement for the specific recovery for a type. It did and has at least provided a method that would be unlikely to do harm, even if it didn't execute a recovery with the least height loss.

It could be said to be at the very least better than chaos. GASCo are at this moment in the process of a study of stall/spin acidents. It will interesting reading when it is completed.

[DB6]

Talking about standard stall/spin recovery is misleading;
Stall recovery: Reduce angle of attack (stick centrally forward, apply full power). If I am not wrong - I don't have first hand knowledge of fast jets etc - this works for ALL fixed wing aircraft and is therefore STANDARD.
Spin recovery: Read this thread. There is no STANDARD spin recovery.

[ProfChrisReed]

My understanding is that for gliders certified to BCAR and then JAR there is a standard spin recovery: full opposite rudder, pause (probably not needed on most gliders); move stick progressively forward until spin stops; centralise controls; pull out of dive.

This is standard in the sense that all such certified gliders need to have demonstrated recovery using this method, from erect spins at least (inverted are outside my knowledge). There may be an alternative method, producing a smaller height loss, but this should work for all. Certainly, this method is taught in the BGA syllabus as the standard method.

Those gliders placarded against intentional spinning are, I believe, so placarded because a recovery is likely to exceed Vne and overstress the airframe; they should still recover, but bits might then fall off. However, I may have got this wrong and don't intend to investigate in flight.

I had thought that JAR required a similar demonstration for powered aircraft (with additional steps for engine management), so that this recovery method could be used successfully on those aircraft even though it might not be the most efficient form of recovery. Is that wrong?

[Dan Winterland]

DB6. Couldn't agree more. It's what I have been saying all along.

Prof. There is a standard spin recovery for gliders - in the BGA syllabus at least. This is because a glider pilot will often fly many types and will need a reaction which will get him out of trouble. Most GA aircraft won't enter a spin unintentionally - this isn't the case for gliders which fly close to the stall and have long wings which experience rapid changes in their angle of attack. Also, they have low B/A ratios which means they are pro recovery. They enter a full spin within a quarter of a turn, but recover (in most cases) pretty quickly. And have very similar characteristics which is why a 'standard recovery' works. In about 600 hrs of gliding, I have entered full spins in gliders several times without intending to, the recovery is rapid and loses nothing like as much height as the GA aircraft would.

With a powered airframe, there are may more factors which will determine the characteristics of the spin. B/A ratios vary massively and will change with factors such as fuel use and C of G.



Quote: "Your Jaguar comments are interesting. Tell more please." The Jag doesn't spin well. Those who have spun it say it's a wild ride. Part of the recovery (eject decision!) is to check the IAS. ut those who have done it say it's hard to actually see the IAS as your head is being banged off the canopy. The 10,000' is for the single seater. The two seater has a 14,000' limit - but I gather only 2 twin seaters have ever been spun. And neither recovered!

I used this as an extreme case. But the Hunter isn't - as applying in spin aileron is a typical recovery for a swept wing aircraft as the moments of inertia can effectively be treated as gyroscopes. And precessing the gyros is the key to effecting the recovery.