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I've always used PARE for spin recovery:

Power to idle
Ailerons neutral
Rudder opposite the spin until rotation stops
Elevator forward to break the stall

What is Beggs/Mueller emergency spin recovery, and why does it work?
Does it work in any aircraft?

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  • $\begingroup$ I was always taught that the E was "Elevator nose down to break the stall" and the dive recovery was a separate thing once the plane is flying again, but as long as you get the plane into a dive you've done the hard part :) $\endgroup$
    – voretaq7
    Dec 19, 2014 at 3:12
  • $\begingroup$ yes, i wrote it wrong, and will fix. $\endgroup$
    – rbp
    Dec 19, 2014 at 3:13
  • $\begingroup$ Who are Beggs and Mueller? I’ve been flying almost 40 years and thought this was called “hands off”… $\endgroup$ Aug 17, 2022 at 14:25
  • $\begingroup$ P.S. Spin recovery techniques are aircraft specific so it may be wise to mention this. (ours used to be stick full aft...) $\endgroup$ Aug 17, 2022 at 15:45

7 Answers 7

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The Beggs/Mueller technique is:

  • engine idle
  • let go of the stick
  • push rudder against spin direction

This was developed for pilots of the Pitts Special biplane and will work well with naturally stable, powered aircraft. With gliders (where it strictly doesn't apply) it will be less effective, but still work in most cases. The better way is to combine both, rudder against the spin and stick forward (your PARE technique), but only until the rotation stops. Then both the stick and the rudder must be neutral until speed is sufficient for the pull-out. Beggs/Mueller is more about avoiding wrong inputs due to confusion than ending the spin in the most direct way.

Spin recovery with the hands off the stick will be slower than with active control input. If the control surfaces are free-floating, natural stability is normally less than what it is with fixed control surfaces. For that reason, the Beggs/Mueller technique is less effective than actively ending the spin with both rudder and elevator. If the pilot does not realize he is in an inverted spin, pushing down will make matters worse, however.

Why rudder against spin direction?

An aircraft spins because something stabilizes both the rotation and the high pitch angle. First the rotation: This is caused by fully separated airflow on the retreating wing while some section on the advancing wing has attached airflow. The high drag on the retreating wing pulls this side of the aircraft backwards, while the lift on the section of wing with attached airflow pulls that side of the aircraft forward. Remember, airflow is mostly coming from below, and the spin motion modifies the local flow direction the more one moves away from the center of the aircraft.

Why elevator forward (Back in inverted spin)?

Now the pitch angle: The center of rotation is ahead of the wing in the forward fuselage. The masses in the forward fuselage produce little centrifugal force, while the masses in the rear fuselage and the tail, having a substantial distance from the center of rotation, produce a substantial centrifugal force which pulls the whole aircraft into a level attitude. Since the aircraft's motion is mainly downward, this inertial moment increases the angle of attack above the stall angle.

To break the spin one needs to end the rotation or the pitch attitude. Since they mutually reinforce each other, one must be ended to end both. On aircraft with long fuselages the rudder is more effective to stop the rotation, while on aircraft with long wings the elevator will be more effective in ending the spin via reducing pitch attitude. The rotation is then stopped by the roll damping of the wing. Using both together will give the best effect, however.

Why engine to idle?

Having some added dynamic pressure on the vertical tail will also help to end the rotation, but then the aircraft will pick up speed very quickly. Setting the engine to idle will avoid falling into this particular trap, but again for the price of a somewhat slower recovery. Sometimes an aircraft needs that added dynamic pressure to end the rotation, so Beggs/Mueller will not work in all cases.

But keep in mind how the Boeing 307 prototype crashed, killing the KLM evaluation commission and several Boeing employees. Asymmetric power was used because the small vertical would not end the spin and caused an overspeed event with subsequent structural failure. So make sure to first try ending the spin with engine idle.

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  • $\begingroup$ Does the mass of air moved by propeller at max rpm always hit the tail during a spin, or could the tail "miss" this airflow? $\endgroup$
    – qq jkztd
    Nov 2, 2019 at 21:35
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    $\begingroup$ @qqjkztd: The fuselage should ensure that some of the accelerated air still hits the vertical, but some displacement from the center of prop wash must be expected. This displacement, however, is more in vertical than horizontal direction due to the falling motion of the spinning plane, the more so the flatter the spin is. Also, the prop operates in a vey high angle of attack region where the blades are stalled on the way down and see large variations in dynamic pressure. Its efficiency will is likely less than half the normal value in a spin. Yours would be a good candidate for a new question. $\endgroup$ Nov 3, 2019 at 8:22
  • $\begingroup$ Thank you for this, I'll ask about it soon. Considering fully developed spin recovery, Müller let go of the stick allows the stick to naturally move back and inside the spin (left spin, left ailerons, elevator up) Ailerons are too often ousted as a powerful means of decreasing asymmetric critical AOA, while elevator ability to do so is overestimated. $\endgroup$
    – qq jkztd
    Nov 4, 2019 at 8:55
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From the fine folks over at EAA, the Beggs/Mueller technique (also sometimes called the "hands-off" spin recovery technique) is:

  1. Power – Off. (presumably they mean "to idle", and not "stop the engine")
  2. Remove your hand from the stick.
  3. Apply full opposite rudder until rotation stops.
  4. Neutralize rudder and recover to level flight.

So essentially the same technique as PARE, except instead of neutralizing the ailerons & pushing the nose over you put your hands in your lap:

Power: to idle
Ailerons: Put your hands in your lap.
Rudder: Full opposite the direction of spin until rotation stops.
Elevator: Your hands should still be in your lap!

The big advantage to the Beggs/Mueller technique seems to be that with your hands off the stick there's no chance of the pilot panicking and yanking back on the stick/yoke and prolonging the spin. It's predicated on the fact that the nose will fall naturally in a stall, breaking the stall and putting the plane into a slight dive.


I can't say as to whether the Beggs/Mueller technique will work in all aircraft, but it should work in any plane that tends to naturally recover from a stall (i.e. one where the nose naturally falls when the plane is stalled) and has otherwise-conventional spin recovery characteristics. That covers every plane that immediately comes to mind, but it's possible there are some with a canard configuration where spin recovery isn't conventional, and the Beggs/Mueller technique may also not be ideal.

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  • $\begingroup$ I'm still interested in why it works $\endgroup$
    – rbp
    Dec 19, 2014 at 3:14
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    $\begingroup$ @rbp The mechanics are essentially the same as PARE - they're variations on the same technique. The rudder is still what's arresting the spin, and Beggs/Mueller counts on the aircraft's natural tendency to "want to fly" to take care of the rest rather than making it something the pilot does and risking incorrect control inputs making things worse. $\endgroup$
    – voretaq7
    Dec 19, 2014 at 3:28
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To answer the part of the question around whether it works for all aircraft, it is important to note that the Beggs/Mueller technique doesn't work for all aircraft, and that you should refer to your POH/AFM to understand the specific techniques that are relevant to the aircraft you are flying.

As an example, this accident report refers to a crash involving a Cessna A150 Aerobat which apparently will not recover from a spin with the Beggs/Mueller technique.

https://www.atsb.gov.au/publications/safety-advisory-notice/ao-2021-025-san-001/

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At the York Soaring Association (northwest of Toronto) we mainly use a Schweizer 2-32 for spin training, which is mandatory for all pre-solo student pilots, as well as advanced spin training for our pilots in the aerobatic training program. The 2-32 was also known as the X-26 Frigate in NASA's astronaut training program and was used as a platform for what they called 'yaw/roll coupling' training. I.E. it spins like crazy! As an aerobatic instructor I've spun the 2-32 many times and the Beggs-Mueller recovery works well in this a/c. However, we stress that pilots review and be familiar with the spin recovery technic of the particular aircraft they will be flying and use the recommended spin recovery method in the POH for that aircraft. Also, that they NEVER intentionally put an a/c into a spin that is not certified for spins! Many glider POH's are pretty sketchy about spin recovery and in that case I would recommend the standard Transport Canada ( or FAA) spin recovery technic. Finally, be especially anal about the weight and balance calculations of your aircraft before doing spins. One other thing; we take high tows for spin training (about 1 mile above ground) because multiple spins can chew up a lot of altitude very fast. Our hard deck for recovery is 2,000 ft. agl, which is not only air law in Canada but just plain common sense. Done properly and safely spins are uber fun and great training exercises.

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    $\begingroup$ Hi, Don, Welcome to Aviation.SE! This answer is interesting, but it doesn't really seem to answer the specific question of what the Beggs-Mueller spin recovery technique is. Could you perhaps add a paragraph describing the technique? On SE sites, we want all answers to actually answer the specific question that was asked, though including additional relevant information such as you've given here is certainly fine. For more information, see How to Answer and the help center. Again, welcome! $\endgroup$
    – reirab
    Aug 14, 2015 at 3:41
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As a flying instructor and CFI many years ago (50 actually, rather embarrassing isn't it), I taught spin recovery on Beagle Pups, Cessna Aerobats, Victa Airtourers (Australian aerobatic aircraft),Tiger Moths and Blanik sailplanes.

The technique in those days was that you should hold the stick back whilst applying full rudder, as with some aircraft if the stick was not fully back the elevator could blanket the rudder.

During my time as an instructor, my brother bought a Tiger Moth and so I taught him to fly it. I was predominantly training pilots in spam cans at the time and in teaching my brother spins, the Tiger reminded me that it was NOT a spam can, with particular regard to the fact that it has virtually no fin in front of a massive rudder. So much so the if you applied full left aileron and full right rudder the Tiger would roll to the right. The rudder had more roll power (secondary effect of rudder) than the ailerons. So, to demonstrate spin recovery in the Tiger, I put it into a right hand spin, talking my brother through it, "Stick back, opposite rudder. . . " only to have the Tiger recover instantly come out of the spin and enter a spin the other way, to the left. That's one mighty powerful rudder. The subsequent recovery from the left spin was made with full right rudder and the stick moving forward.

The episode reminded me what my maths teacher said when I got an algebra problem wrong,"It's not so important to get the right answer, as to understand the method".

You live (hopefully) and learn. Pete.

PS. The Boeing 747 stall recovery (in the Sim) was also a very enlightening exercise . . . if you are interested. Pete.

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  • $\begingroup$ I suspect it was less the rudder than the dihedral which made the Moth roll. Of course the rudder is needed for the sideslip, but once that is established, dihedral causes the roll. $\endgroup$ Aug 18, 2022 at 9:55
  • $\begingroup$ Agreed.A combination of $\endgroup$ Aug 22, 2022 at 4:45
  • $\begingroup$ A combination of Dihedral, Blanketed wing, Retreating wing with lower airspeed. $\endgroup$ Aug 22, 2022 at 4:47
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Eric Muller was a Swiss architect who was very active in aerobatics in the ‘70s and ‘80s. He won Swiss and European championships and was well known around the world. He wrote a book on aerobatic techniques (with Annette Carson) ‘Flight Unlimited’ in 1983 which was updated in 1995 by Ms Carson after Eric’s passing in 1990 which was medical, not aviation related. It is a good book (and is still available) and the chapter on spins is comprehensive, going into great detail about tail configurations and the best elevator positions for spin recovery because of them. In short, there can be significant shielding of the rudder by the tail plane and elevator in upright spins in some aircraft which can be made worse by forward stick applied prematurely. The primary anti-spin control is full rudder opposite to the yaw as seen by looking down the top of the engine cowling. Jamming the stick fully forward in some aircraft will not only shield the rudder and delay recovery but can rapidly transition the upright spin into an inverted spin. Try it in a Pitts! It is called a ‘Crossover Spin’. Gene Beggs was a Texan flight instructor who built a Pitts S1 (‘72-‘77) so he could compete in higher classes of aerobatic competition. He was almost killed twice in his Pitts after getting into spins inadvertently, in fact dozens of people were killed as a result of not recovering from spins in Pitts Specials. Gene took a keen interest in spins and really took notice when he read an article about recovery written by Muller, which suggested that the best method to recover from an inadvertent spin especially if there was any confusion about whether the spin was upright or inverted was to “Close the throttle, let go of the stick and apply full rudder opposite to the yaw”. Beggs tried this in his Pitts and knew that he had found the solution to a problem that had been plaguing the aerobatic scene in the USA, which was dominated by the Pitts, and had been really gnawing at him. He devised a spin training course and wrote a book ‘Spins in the Pitts Special’ which is still available. There is no spin in the Pitts that will not recover by this method. The controls trail in the airflow (elevators nose up, ailerons into the roll) until the yaw stops and then the stick snaps into the centre by itself. However, after initially not wanting to talk about other types, people came to him and Gene subsequently flew many types and found that in some aeroplanes, in some upright spins, the elevators would stay locked in the stick back position and take some force to get forward. Right spins in the T6/SNJ/Harvard was one example, the turbine-engined Beech Mentor was another and the humble Cessna 150 was another. There are probably more… To finish, let me say that the correct spin recovery actions are type specific. eg the Chipmunk (where the tail plane and elevator do not shield the rudder) needs progressive forward stick, right to the stop if necessary and hold it there. Also check pre aerobatics that the park brake is fully off or rudder bar movement can be restricted. The Extra will not recover from some fully developed spins without ailerons into the roll component ie opposite to the anti-spin rudder when upright and the same side as the anti-spin rudder when inverted. Do your research, get competent instruction in two-seaters by Old Hands and Wise Heads. Happy Landings.

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Gene Beggs calls this the ‘Emergency Spin Recovery’ and it is specifically for Pitts Specials. He says “After cutting the power and releasing the stick, the pilot has eliminated any concern about whether the spin is upright or inverted. With the hand completely removed from the stick, it is impossible to make an error in control input. It is impossible to reverse the spin with rudder. It is impossible to transition from upright to inverted or vice versa. The Emergency Spin Recovery involves no reference to flight instruments. The pilot must decide only whether to use full left rudder or full right rudder. When trying to determine which rudder pedal to use, these are important points to remember. You must look down the top of the engine cowling at the ground so you will always see yaw in the correct direction. You should see the fuel cap in your field of view. The recovery rudder pedal will be displaced closer to you when you take your feet off both pedals. [when both pilots have their feet off - Forbes] When you push this pedal, it will travel farther and be harder to push….” Even in types other than Pitts Specials the above actions are a good start in an emergency and or where there is confusion and disorientation. After that, while still holding absolutely full anti-spin rudder, if you find the stick/yoke ‘locked’ aerodynamically, manually put it where it should go. If it is displaced rearwards push it forward and vice versa. Remember the type specific actions you should know like the Chipmunk needing up to full forward stick to stop an upright spin, the in-spin (roll component) aileron needed in Extras and maybe some other types with full-span ailerons and the white dot painted in the instrument panels of some Yaks indicating where to put the stick.

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    $\begingroup$ Welcome to aviation, one answer is sufficient and can be updated using the edit link. Your (aggregated) answer would benefit from some formatting (specifically, paragraphs) $\endgroup$
    – Jamiec
    Jan 19 at 13:13

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