My Spin Crusade

It has been about 50 years since I did my first spin in an aeroplane, about 35 years since I started teaching spins to other pilots and about 15 years since I started teaching other instructors how to teach spins.

In the last ten to twenty years in Australia there have been two significant and related improvements to the knowledge associated with spinning. The first is the internet – before Google it was just so difficult to get good information. The flight manuals mandated by CASA’s predecessor were to a fixed template of limited scope which did not include information on spin recovery procedures. The flight manual developed by the manufacturer overseas and approved by the FAA, if from the USA, was required to be discarded.

How lucky was I to have the opportunity to fly a brand new Pitts S-2A in the ’80s. It came out of the box with its original flight manual, the first time I had seen one despite flying Pitts for about ten years. We had some handling notes based on the Pitts Owners and Service Manual plus that silly Australian-specific flight manual. (In another article later I will go into more detail as to why it was silly.) Guess which was the only document which described the recovery technique from a flat spin? This was in the days long before the Beggs-Mueller technique. I’ll never forget one unintentional spin from a lomcevak in practice for an airshow “why doesn’t this stop spinning” I was thinking. When I flew the airshow the next day I flew that lomcevak at quite a much higher altitude.

Flying schools were required to provide pilots with handling notes which were “accepted” by the local office of CASA’s predecessor – there was no standard so the content was variable – even for the same type between different flying schools. The text of handling notes would often conflict with the original flight manual! There were some generic POHs available for sale for the more common types but pilots, of simple types especially, were not directed to them. These were the days before personal computers so every document had to be laboriously created and printed.

Finally, around 2000, CASA changed the flight manual system to discard the Australian-specific manuals and revert to the original. However many owners found it difficult to acquire flight manuals applicable to aeroplanes 20 to 30 years old by then and gave up. I still see a lot of aerobatic aircraft with the old Australian-specific manuals or the wrong manual of some sort – importantly, the aircraft does not have the correct flight manual which is one of the documents legally required – and it is important.

Over these years I have become concerned with the number of spin endorsed pilots who don’t know the correct spin recovery technique. The number of instructors with spin training endorsements who do not know the correct spin recovery technique makes me angry. People whisper in my ear about their scary experience when a spin takes a very long time to recover and I ask what technique they use – when they tell me I respond with “You are very lucky that you did not die using that technique!”

CASA’s Flight Instructor Manual is quite clear:
“To recover, first ensure that the throttle is closed, ailerons neutral and the direction of turn identified. This is followed by application of full opposite rudder. After a brief pause ease the control column forward progressively until the spinning stops. Centralize the rudder and ease gently out of the resulting steep dive, levelling the wings.”

The FAA’s Airplane Flying Handbook is more comprehensive:
“In the absence of the manufacturer’s recommended spin recovery procedures and techniques, the following spin recovery procedures are recommended.
Step 1—REDUCE THE POWER (THROTTLE) TO IDLE. Power aggravates the spin characteristics. It usually results in a flatter spin attitude and increased rotation rates.
Step 2—POSITION THE AILERONS TO NEUTRAL. Ailerons may have an adverse effect on spin recovery. Aileron control in the direction of the spin may speed up the rate of rotation and delay the recovery. Aileron control opposite the direction of the spin may cause the down aileron to move the wing deeper into the stall and aggravate the situation. The best procedure is to ensure that the ailerons are neutral.
Step 3—APPLY FULL OPPOSITE RUDDER AGAINST THE ROTATION. Make sure that full (against the stop) opposite rudder has been applied.
Step 4—APPLY A POSITIVE AND BRISK, STRAIGHT FORWARD MOVEMENT OF THE ELEVATOR CONTROL FORWARD OF THE NEUTRAL TO BREAK THE STALL. This should be done immediately after full rudder application. The forceful movement of the elevator will decrease the excessive angle of attack and break the stall. The controls should be held firmly in this position. When the stall is “broken,” the spinning will stop.
Step 5—AFTER SPIN ROTATION STOPS, NEUTRALIZE THE RUDDER. If the rudder is not neutralized at this time, the ensuing increased airspeed acting upon a deflected rudder will cause a yawing or skidding effect. Slow and overly cautious control movements during spin recovery must be avoided. In certain cases it has been found that such movements result in the airplane continuing to spin indefinitely, even with anti-spin inputs. A brisk and positive technique, on the other hand, results in a more positive spin recovery.
Step 6—BEGIN APPLYING BACK-ELEVATOR PRESSURE TO RAISE THE NOSE TO LEVEL FLIGHT. Caution must be used not to apply excessive back-elevator pressure after the rotation stops. Excessive back-elevator pressure can cause a secondary stall and result in another spin. Care should be taken not to exceed the “G” load limits and airspeed limitations during recovery. If the flaps and/or retractable landing gear are extended prior to the spin, they should be retracted as soon as possible after spin entry.
It is important to remember that the above spin recovery procedures and techniques are recommended for use only in the absence of the manufacturer’s procedures. Before any pilot attempts to begin spin training, that pilot must be familiar with the procedures provided by the manufacturer for spin recovery.”

I have added the bold to some of the above text so let’s consider those items further.

The spin recovery procedure described is generic and it is essential to use the procedure provided by the manufacturer – remember that they have undertaken substantial flight tests to determine the behaviour in a spin and to prove the recovery technique. To emphasise this, all pilots, especially all spin instructors should read the ATSB’s report of the 2014 accident to a Chipmunk at https://www.atsb.gov.au/publications/investigation_reports/2014/aair/ao-2014-114/

The first four steps in the FAA’s Handbook are identical to the NASA Standard Spin Recovery Method (see AIAA Paper 86-2597) which has been distilled by Rich Stowell into the PARE® mnemonic.

All four actions of PARE® must be done for the spin to stop. There are some other actions afterwards.

It is particularly annoying to see stuff like the following text on a website such as https://blog.globalair.com/post/aircraft-spins-101.aspx
“Recovery procedures are specific to the aircraft flown and are found in the pilot operating handbook of each aircraft. In light aircraft, the spin recovery procedures follow a typical pattern and can be remembered by the common acronym PARE®.
P – Power: The throttle should be moved to the idle position to reduce thrust.
A – Ailerons: Ailerons should be neutralized.
R – Rudder : Full opposite rudder input should be applied until the rotation is stopped. If the aircraft is rotating to the left, right rudder should be applied. Once the spinning stops, the rudder should be neutralized.
E – Elevator: Quick forward pressure should be applied to break the stall and gain airflow over the wings. Once the aircraft gains lift, back pressure should be applied gradually so as not to stall again.”

Please, if you are going to use PARE® to recall the spin recovery technique then get it right. True, neutralise the rudder once the spin stops but that won’t happen (in a typical fully developed spin) until after the next step of moving the elevator. That website suggests that you use the elevator to “break the stall” after the spinning stops however CASA, NASA and the FAA are quite clear: When the stall is “broken,” the spinning will stop. It is true that some aircraft have a rudder powerful enough to stop the rotation by itself in a fully developed spin but here we are discussing the generic technique.

Let’s move on to consider some examples of specific techniques.

For the Cessna 152:
1. VERIFY THAT AILERONS ARE NEUTRAL AND THROTTLE IS IN IDLE POSITION
2. APPLY AND HOLD FULL RUDDER OPPOSITE TO THE DIRECTION OF ROTATION
3. JUST AFTER THE RUDDER REACHES THE STOP, MOVE THE CONTROL WHEEL BRISKLY FORWARD FAR ENOUGH TO BREAK THE STALL. Full down elevator may be required at aft center of gravity to assure optimum recoveries.
4. HOLD THESE CONTROL INPUTS UNTIL ROTATION STOPS. Premature relaxation of control inputs may extend the recovery.
5. AS ROTATION STOPS, NEUTRALIZE RUDDER AND MAKE A SMOOTH RECOVERY FROM THE RESULTING DIVE.

Pretty much exactly what the FAA describes as the generic technique.

The Cessna 150 is similar. I recall a flight with one instructor trainee who was an experienced pilot. Upon recovery from his spin demonstration he applied full opposite rudder and continued to hold the yoke full back. The aeroplane simply kept spinning. He gave me a quizzical look and I responded with: “Just move the yoke forward.” He was testing me as he had some bad experiences with instructors previously.

Now for the Super Decathlon Flight Manual:
Recover with Positive Movement of Stick to Neutral Position & Opposite Rudder Until Rotation Stops – Then Neutral Rudder & Smooth Recovery from Dive to Level Flight.
Free Release at Control is Not Adequate for Recovery.
Positive Movement of Controls by the Pilot is Required for Spin Recovery.

The Operating Manual has this additional information:
1) Throttle – Closed
2) Ailerons – NEUTRAL POSITION
3) Rudder – FULL DEFLECTION in the opposite direction to the rotation
4) Elevator – POSITIVE FORWARD TO NEUTRAL (free release of the elevator control is not adequate for recovery)
5) Rudder – NEUTRALIZE when rotation stops and positive control and flying speed is restored
6) Nose Attitude – RAISE smoothly to level flight attitude
7) Throttle – only after recovery from diving attitude, then as required

Again, pretty much exactly what the FAA describes as the generic technique.

Other variants of the Decathlon are the same. I recall a flight with one instructor trainee. As a flight examiner I had previously failed him on his test for the spin training endorsement because of his dangerously incorrect knowledge – he was adamant that PARE® meant power off, aileron neutral, opposite rudder and elevator to pull out of the dive. He had absolutely no idea what the flight manual said about spin recovery. On this flight I gave him an opportunity to demonstrate recovery per his earlier briefing to me. After a couple of turns we were definitely in a fully developed spin and, a surprise to him, it simply continued spinning … and spinning. Stick forward and it recovered!

I have seen that wrong explanation of PARE® so often from spin-endorsed pilots that the standard of spin instruction makes me angry. I have experimented on occasion and not corrected someone during the briefing so I could observe their performance in flight. With the opposite rudder they inadvertently relax the back pressure and the stick moves forward enough to recover the spin. Another factor is that they do not let the spin develop fully – in the incipient spin stage the aeroplane is very easy to recover.

As some people very well know, there are some spin modes for the Decathlon where it takes a positive push to move the stick from the aft stop. Read those instructions in the manual again – it specifically addresses this characteristic.
PARE® is the thing to remember but get the detail right.

I have a short quiz about spinning on my website at http://ozaeros.net.au/?page_id=252 (the password is quiz). Why do so many people have the incorrect understanding of PARE®? Why do so many people believe that the elevator is used to unstall the wings only after the rotation stops?

I long ago ceased wondering how this situation arose. A combination of a few things but the root cause is people taking a shortcut to getting the qualification. Instructor trainees don’t bother to read the Flight Instructor Manual or the Flight Manual.

If they are using the incorrect technique surely it would become obvious during the flight exercises? It should and does but only if the aircraft has entered a fully developed spin. If spin exercises are limited to about one turn then the aircraft will recover easily, typically by relaxation of the pro-spin controls. If the aircraft is let develop spiral dive characteristics then the autorotation typically ceases by itself.

I have also seen trainees who were taught the correct information and then get off track by themselves. i.e. the training did not sink in – what’s that about assessing competence per the flight instructor standards? I know that it is not easy however it is important to do more than just present the knowledge in a pre-flight briefing, demonstrate spin recovery and observe the trainee repeat that technique on the one flight.

An earlier ATSB report is interesting in this context http://www.atsb.gov.au/publications/investigation_reports/1978/aair/197805178/
“The pilot was an experienced flying instructor and aerobatic pilot and held a general authorisation to conduct aerobatic flying below 3000 feet but not below 500 feet above ground level. …
… after completing his aerobatic display, which commenced with a spin, he commented that the spin had been made with engine power on and more height had been lost during this manoeuvre than he had intended. …
On the next morning … At a height variously estimated from 2000 to 4500 feet above ground level … Engine power was then heard to decrease and the aircraft entered a spin, probably to the left although one of several witnesses believed it was to the right. As the spin progressed, the nose attitude appeared to steepen to the near vertical. After making four complete turns, and after the fifth turn commenced, the aircraft struck the ground ….
It was established that it was the normal practice of the pilot, when performing aerobatics, to set the altimeter of his aircraft to indicate the height above ground level. The altimeter of VH-ERB was found to be set to indicate the altitude above mean sea level …
The probable cause of the accident was that the pilot, for reasons which have not been established, did not take timely action to recover from an aerobatic manoeuvre at a safe height.”

There is one common factor in both of these accident reports. The Chipmunk in 2014 had the obsolete Department of Transport Flight Manual. “In Australia prior to 2002, CASA and its predecessors prepared, approved and issued AFMs for light civil aircraft. The flight manual in use for UPD was one such manual, approved specifically for that aircraft by CASA’s predecessor in 1988. It did not include guidance on spin recovery.”
VH-ERB also had one of those flight manuals with nil guidance on spin recovery.

The observed steepening of the nose attitude indicates an accelerated spin which results from moving the stick forward before opposite rudder leading to a delayed recovery. It is unfortunate that the investigators did not seek out the spin recovery procedure that the pilot would’ve been known to use.

The only safety issue identified by the ATSB in that 2014 Chipmunk accident report was addressed to the specific flying school:
“The spin recovery methods taught by the flying school were inconsistent across instructors and training material, and were not always appropriate for the Chipmunk aircraft type used by the school.”
My opinion is that it is a much more general reoccurring safety issue which needs to be addressed regularly. I’d reinforce the contents of the CASA Flight Instructor Manual (supported by the FAA Flying Handbook) and the Flight Manual of the specific aircraft used. Of course, it is essential to have the current correct flight manual – I still see those old Department of Transport flight manuals in aerobatic aircraft! My opinion is that instructors should also read the book Stall, Spins and Safety by Sammy Mason – they need to know more than the minimum knowledge that their students must be taught. I find it amazing that inexperienced instructors and instructor trainees can just invent stuff, or at best apply some quite specific bit of information as if it was generic gospel – very dangerous.

Finally, PARE® per Rich Stowell from his excellent book Stall/Spin Awareness:
1. Power – Off.
2. Ailerons – Neutral (+ Flaps Up).
3. Rudder – Full Opposite and Held.
4. Elevator – Through Neutral.
Hold these inputs until rotation stops, then:
5. Rudder – Neutral.
6. Elevator – Easy Pull to Straight and Level.

Remember that, it is really not that hard to get it right.

Comments

  1. I note CASA say “After a brief pause EASE the control column forward progressively until the spinning stops.” … where everybody else (including my instructor, Bob Tait) says ” apply a POSITIVE AND BRISK, STRAIGHT FORWARD MOVEMENT OF THE ELEVATOR CONTROL FORWARD OF THE NEUTRAL TO BREAK THE STALL. Ease, against Positive … the former just delays recover, whilst losing even more precious altitude. On what grounds does CASA modify this? …surely CASA really carries some liability for such alternative advice.

    What gives, these “Australian conditions … ” … what the hell is so unique about Australia?

    1. “where everybody else … says ELEVATOR CONTROL FORWARD OF THE NEUTRAL” – don’t include me in that as I generally teach spins in the Super Decathlon which is elevator to the neutral position.

      How far forward of neutral? A little bit, a lot, or maximum? What types does that apply to?

      “Ease, against Positive … the former just delays recover” – not necessarily, it depends on the type.

      “On what grounds does CASA modify this?” They may ask the same of what you state! Seems to me that CASA’s instructions apply to the Tiger Moth which was commonly used when CASA first wrote that document. It is long overdue for an update.

      ”what the hell is so unique about Australia?” Well, my opinion is the overall poor standard of knowledge amongst flight instructors.

      From NASA TN D-6575, Summary of Spin Technology as related to Light General Aviation Airplanes, “the so-called NACA recommended spin-recovery technique: Briskly move the rudder to full against the spin; after the lapse of appreciable time (approximately one-half turn), briskly move the elevator to approximately full down, and hold these controls until the recovery is complete.”

      It goes on to state “ that when these results were obtained in 1935, the airplanes of that day probably were in the zero loading condition previously discussed and today this recovery technique would apply only for airplanes that have similar loadings. As previously pointed out, the control technique required for spin recovery is primarily dictated by the mass distribution in the airplane. Therefore, for airplanes of different loading conditions, this control technique recommended in 1935 would probably not apply.”

      The current FAA AC 23-8C, Flight test Guide for Certification of Part 23 Airplanes, states: “Recoveries should consist of throttle reduced to idle, ailerons neutralized, full opposite rudder, followed by forward elevator control as required to get the wing out of stall and recover to level flight.”

      For this discussion the key words are “forward elevator control as required”.

      (It goes on to state that: “For acrobatic category spins, the manufacturer may establish additional recovery procedures, provided they show compliance for those procedures with this section.”)

      The use of elevator control – the amount and rate of movement is specific to the type!

      CASA’s AC 61-16v1.0, Spin avoidance and stall recovery training, makes this important statement:
      “Certification for intentional spins will be stated in the aircraft flight manual, along with any entry and recovery inputs particular to that aircraft …”

      CASA only requires pilots to know the spin recovery method applicable to the type they undertake spin training in. Spin instructors are not required to know any more. If that is all one knows then a fatal surprise may be the outcome. A sad state of affairs.

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