Mooney Stalls and Spins

[Rspencer612]

Well I picked up my beloved Mooney M20J Missile today from its new Dynon panel install. Wow is it sweet!  The last thing needing calibrated was the AOA, which requires some stalls in the various configurations to be done. 
 

so I had done stalls in my M20C a handful of times years ago and have recently done a bunch in my 182. all went great and I did not lack confidence!  Up I go, from a 1000’ elevation runway to 6500 feet. I have always preferred to have 5000 feet min for air work and as a jet driver and GA airplane broker am flying very regularly. As you know the Missile is 300HP IO-550 with a full feathering 3 blade prop. So it’s quite nose heavy with a forward CG making it an inherently stable platform.  
 

I began with a clean LOW power, power on stall at about 14” manifold pressure otherwise the plane just gets an insane deck angle. Even this angle was very nose high. As the plane got slow my slip indicator continued to go out right so I began to give the airplane gentle right rudder while holding the wings level. Well down right to about 58-60 kts indicated, the right wing aggressively dropped 90-100 degrees and the nose broke pointing down about 15 degrees. At that point the airplane began to wind into a spin. I smoothly but rapidly pushed, rolled left and applied heavy left rudder. The airplane was instantly reactive and recovery to straight and level was quick with about a 500-600 foot loss of altitude. 
 

this sure caught me off gaurd, but now I was prepared for what just caught me off gaurd. I did 2 more stalls in both landing config with full flaps and approach/departure with gear down and half flaps. Each stall attempted to react the exact same way with engine power around 10” manifold pressure. As I was prepared for these, the right wing only rolled off about 45 degrees each time instead of the big roll accelerating into a spin like the first one. Immediate left rudder and nose down corrected it. 
 

im very focused on keeping the airplane coordinated as the missile needs a lot of rudder input often with the 300Hp. So I wonder if keeping it coordinated applying the slight right rudder and wings level was creating the condition?  I didn’t try one uncoordinated with no rudder which may have answered my question on that. 
 

anyways, any Missile or Rocket owner’s experience this. Did I cause this or is this a symptom of the Mooney and the conversion?  While the first caught me off gaurd, I was never uncomfortable, nor was the airplane non reactive to proper recovery inputs, but it sure seems more prone to it then I expected. 
 

on a side note the AOA is beautifully calibrated now and I intend in the future to not be close to this limit, but it did make me think a low altitude stall in this plane has a recipe for disaster!
 

 

[A64Pilot]

Stay OFF the ailerons if trying to prevent a spin, honestly don’t touch them doing stalls, use your feet to pick up a dropped wing. Reason is if it’s beginning to spin to the right, that’s because the right wing has stalled, when you add left aileron to stop the right wing dropping, you are trying to increase lift on the stalled wing, which you can’t, it’s stalled so what is likely to happen is you deepen the stall and make the incipient spin more likely.

Its hard not to do, and I believe it’s just an ingrained response in all of us to correct a low wing with aileron, so I believe most of us, including me may go to aileron in an unexpected stall, simply because we don’t recognize the stall yet.

Power on stalls in big motored airplanes can be real scary, even at low power. 20” of power in a C-210 gear and flaps up is scary, you cannot stop the spin entry. I can’t imagine an honest full power departure stall.

‘If you can you definitely want to be co-ordinated, the C-210 you can’t rudder is buried and the ball starts coming out, then it stalls at only 20”.  Stalls with the ball out can get ugly fast, that is what gets people on the turn to final sometimes, they overshoot or see they are going to and push rudder likely without realizing it to get back in and she stall and starts to spin.

That is exactly what kills more Ag pilots than anything using rudder to tighten up a turn.

[Shadrach]

I’m sure some Rocket/Missile owners will reply.  I have only stalled a handful of Mooneys and never a Missle but yours is the first I’ve heard that breaks to the right in power on stall.

As an aside, I’m of the opinion that practicing stalls is a good idea. However for AOA calibration, I would think taking it to the buffet would be adequate.

[bcg]

I fly a C so, it's not the same but in stalls I need a LOT of right rudder to stay coordinated, especially power on stalls. I typically just take them to the buffet, I'm still low hours and don't want to end up in a spin so err on the side of caution.

I don't know if that's helpful at all, just thought I'd share.

Sent from my Pixel 6a using Tapatalk

[ilovecornfields]

I would recommend practicing stalls/spins with an appropriately experienced CFI. I have not had this issue with my Ovation and with VGs it doesn’t really “break” but just mushes. You mentioned you got a new panel. Is the slip/skid indicator appropriately calibrated?

Your spin recovery worked, but I agree with @A64Pilot that it is usually recommended NOT to use the aileron to pick up a wing in a stall. 30 years ago I was taught “stick neutral, opposite rudder.” Now it’s PARE (power to idle, ailerons neutral, opposite rudder, elevator forward). Either way, I think it’s generally advised to avoid using the ailerons in an stall for the reasons described in the earlier post.

[Rspencer612]

I kept it coordinated with the right rudder, but I was wondering if that right rudder to keep it coordinated cause the right roll off?  Curious would it be better or worse if you left rudder neutral, let plane coordination be off and hold wings level during the stall?

 

also curious if this is an exacerbated response due to the high power engine conversion or more typical or all Mid/long bodies?

[Rspencer612]

3 minutes ago, ilovecornfields said:

I would recommend practicing stalls/spins with an appropriately experienced CFI. I have not had this issue with my Ovation and with VGs it doesn’t really “break” but just mushes. You mentioned you got a new panel. Is the slip/skid indicator appropriately calibrated?

Your spin recovery worked, but I agree with @A64Pilot that it is usually recommended NOT to use the aileron to pick up a wing in a stall. 30 years ago I was taught “stick neutral, opposite rudder.” Now it’s PARE (power to idle, ailerons neutral, opposite rudder, elevator forward). Either way, I think it’s generally advised to avoid using the ailerons in an stall for the reasons described in the earlier post.

Yea, I definitely poorly described my recovery above. I didn’t roll ailerons out until the spin was neutralized which I did by left rudder and push of the yoke. The push was because I was in a heavy pull to go into the stall. So it was more of a push to neutral. So it was push, left rudder, spin stopped, I was 15+ degrees nose down and banked 100-120 degrees, airspeed instantly increased to about 85-90 knots and a began to roll wings level and pull out. Airspeed was about 130kts with a loss of 500-600 feet at completion. Hope that better describes the method I used which is consist with what I was taught and what y’all are mentioning. 

[A64Pilot]

She may have a benign stall power off, but put some power to her, I guarantee you she will turn on you and show you her ugly side

[A64Pilot]

39 minutes ago, Rspencer612 said:

I kept it coordinated with the right rudder, but I was wondering if that right rudder to keep it coordinated cause the right roll off?  Curious would it be better or worse if you left rudder neutral, let plane coordination be off and hold wings level during the stall?

 

also curious if this is an exacerbated response due to the high power engine conversion or more typical or all Mid/long bodies?

You had right rudder because you were carrying power, no keeping the ball centered shouldn’t have made the wing drop, but torque may have, either way power off and get onto lots of left rudder will bring the right wing back up. I’m not one for always shoving the nose down however on airplanes with a very forward CG, but some airplanes after several turns have a tendency to flatten out, those may need the sharp push down, but by that time the spin has developed

To answer you question better is as soon as the wing drops as she stalls get on opposite rudder to raise dropped wing, ball be damned.

You in Fl? If so I know a good aerobatics instructor with a Zlin and or a Pitts that will teach you spins until your comfortable

https://www.iac.org/flight-school/wingover-aerobatics-llc

 

[mike_elliott]

If your power off coordinated stalls also resulted in a right wing dropping, Have rigging checked and also stall strip placement

[Rspencer612]

2 minutes ago, A64Pilot said:

You had right rudder because you were carrying power, no keeping the ball centered shouldn’t have made the wing drop, but torque may have, either way power off and get onto lots of left rudder will bring the right wing back up. I’m not one for always shoving the nose down however, but some airplanes after several turns have a tendency to flatten out, those may need the sharp push down, but by that time the spin has developed

To answer you question better is as soon as the wing drops as she stalls get on opposite rudder to raise dropped wing, ball be damned.

You in Fl? If so I know a good aerobatics instructor with a Zlin and or a Pitts that will teach you spins until your comfortable

https://www.iac.org/flight-school/wingover-aerobatics-llc

 

Fair enough!  I feel I did get full left rudder when I pushed it. There was no “lifting” the wing immediately. It just stopped the spin, which airspeed then increased with the nose down and all controls became fully responsive.
No I’m not in Fl, I am in TX. Would be fun to do some recurrent spin training so I think I will now!  Certainly always room to learn when it comes to flying, no matter where you are in your career, personal flying, or training!

[Rspencer612]

6 minutes ago, mike_elliott said:

If your power off coordinated stalls also resulted in a right wing dropping, Have rigging checked and also stall strip placement

Stall strips in place where required, Rigging was just confirmed at this annual by IA. Said it was spot on with the M20J service manual……

[carusoam]

Interesting pirep!

Thanks for sharing the details…

The O stalls straight ahead, nicely coordinated… 280hp or 310.

Power on, is interesting… because full power isn’t typically used.  
 

One thing that may be different…

Surface area of the tail feathers of the LBs is a bit larger than the mid bodies…

The LBs also have rudder trim to help staying coordinated in the T/O configuration…

 

+1 for determining what is causing the uneven break…

Let’s invite @Seth to the conversation… Seth is a Missileer… 

Pp thoughts only, not a CFI…

Best regards,

-a-

[Fly Boomer]

1 hour ago, A64Pilot said:

Stay OFF the ailerons if trying to prevent a spin, honestly don’t touch them doing stalls, use your feet to pick up a dropped wing. Reason is if it’s beginning to spin to the right, that’s because the right wing has stalled, when you add left aileron to stop the right wing dropping, you are trying to increase lift on the stalled wing, which you can’t, it’s stalled so what is likely to happen is you deepen the stall and make the incipient spin more likely.

@Rspencer612 please carve this in stone.

[Fly Boomer]

2 hours ago, Rspencer612 said:

Each stall attempted to react the exact same way

I would at least entertain the possibility that one or more stall strips have been moved -- it sure didn't leave the factory with those violent stall characteristics.  Does your airplane have TKS?  If so, those stall strips are just stuck on the leading edge by the TKS installer, and it doesn't take much deviation from the factory location to make a big difference in stall behavior.

[Echo]

I have Missile experience.  Not normal for a severe wing drop with ball centered.  If NOT coordinated, yes a very aggressive wing drop will happen in a Missile and in short bodied Mooney in my experience.  I only had it happen once and I did NOT like it one bit.  Glad I was under instruction at the time because I was definitely surprised.  No spin, but I was looking at the ground in a half beat.

[PT20J]

1 hour ago, Rspencer612 said:

Stall strips in place where required, Rigging was just confirmed at this annual by IA. Said it was spot on with the M20J service manual……

Stall strip location can only be confirmed by flight test. There is a procedure in the service and maintenance manual. Certification limits are 15 deg max roll within one second of the stall break. M20J service manual has the same limits. Mooney flight tested each airplane and placed the strips accordingly for each due to manufacturing tolerances. This should have been done again after missile conversion. Not sure what has changed, but if you were coordinated at the stall it shouldn’t behave as you described.

[Shadrach]

11 hours ago, A64Pilot said:

You had right rudder because you were carrying power, no keeping the ball centered shouldn’t have made the wing drop, but torque may have, either way power off and get onto lots of left rudder will bring the right wing back up. I’m not one for always shoving the nose down however on airplanes with a very forward CG, but some airplanes after several turns have a tendency to flatten out, those may need the sharp push down, but by that time the spin has developed

To answer you question better is as soon as the wing drops as she stalls get on opposite rudder to raise dropped wing, ball be damned.

You in Fl? If so I know a good aerobatics instructor with a Zlin and or a Pitts that will teach you spins until your comfortable

https://www.iac.org/flight-school/wingover-aerobatics-llc

 

Wouldn’t Torque cause a left break? My plane always rolls left performing power on stalls

[Rspencer612]

7 minutes ago, Shadrach said:

Wouldn’t Torque would cause a left break? My plane always rolls left performing power on stalls

Yea, your correct, should go left if torque related. 

[Rspencer612]

11 minutes ago, PT20J said:

Stall strip location can only be confirmed by flight test. There is a procedure in the service and maintenance manual. Certification limits are 15 deg max roll within one second of the stall break. M20J service manual has the same limits. Mooney flight tested each airplane and placed the strips accordingly for each due to manufacturing tolerances. This should have been done again after missile conversion. Not sure what has changed, but if you were coordinated at the stall it shouldn’t behave as you described.

They are in the same spot as another M20J in the shop, so I assumed correct…..I have no clue what rocket engineering did when it was there…..

[PT20J]

The right rudder counteracts the torque if you keep the ball centered. The decrease in wing lift at the stall doesn’t change that. But it takes increasing rudder as the airplane slows because the torque is (mostly) constant but the rudder becomes less effective. 

[Rspencer612]

I mean it’s certainly possible I wasn’t properly coordinated at the stall with enough or not enough right rudder, but I was actively watching it and correcting thorough the manuevers and got the similar result in all three. 

[N231BN]

If it broke to the right you were most likely giving it too much rudder. Make sure your instrument panel is level, they tend to sag to the right which would require more than normal rudder input to give you the indication of being coordinated.

[Shadrach]

47 minutes ago, Rspencer612 said:

I mean it’s certainly possible I wasn’t properly coordinated at the stall with enough or not enough right rudder, but I was actively watching it and correcting thorough the manuevers and got the similar result in all three. 

More right rudder would exacerbate the tendency to break to the right. 
 

[Rspencer612]

14 minutes ago, Shadrach said:

More right rudder would exacerbate the tendency to break to the right. 
 

Yea I understand that completely. But I sure think I saw and it felt it was coordinated at the break, which required a steady pressure on the right rudder……