76 M20C rigging

[BillYesIAm]

In hands-off (and feet off) flying my plane banks to the left, regardless of wind, tank levels, altitude, etc.

The ball stays centered.

The ailerons appear to be in sync but we will check that in more detail.

My mechanic thinks it might be the trim tab on the vertical stabilizer so we will be checking that soon.

There is something else of concern to me that I think might be related to this problem. The left tip of the horizontal stabilizer is about 1.5 inches higher than the right tip. I have checked it a few times on level surfaces, first verifying levelness of the wings. Is this normal? If not, what might cause this? Also, could this have anything to do with the banking issue?

Thanks,

Bill

South Carolina
 

[Yetti]

Do you have a PC system?  There is a knob you can turn to change the level.   Also weight and fuel weight

[David Lloyd]

When it comes to rigging, the absolute first step is to make certain the ball is centered when the aircraft is level.  Not verifying this, everything else is a waste of time.  

[BillYesIAm]

4 hours ago, Yetti said:

Do you have a PC system?  There is a knob you can turn to change the level.   Also weight and fuel weight

Sorry, I should have included that information. The PC system was disabled over 20 years ago. I am running an STEC 50 auto pilot instead.

[BillYesIAm]

2 hours ago, David Lloyd said:

When it comes to rigging, the absolute first step is to make certain the ball is centered when the aircraft is level.  Not verifying this, everything else is a waste of time.  

When the aircraft is level the ball is centered. As soon as I take my foot off the right rudder pedal the aircraft banks left and the bank continues to increase until I correct with right rudder and aileron input. I also noted that while it is in the left bank the TC shows the aircraft turn to be coordinated. If I keep the Aircraft level with just the ailerons then the ball in the turn coordinator is very slightly to the right. Almost not noticeable.

[Yetti]

Some of that is P factor.  My instructor showed me how to do the pattern turn to the left was just let up a little bit of right rudder you put in from takeoff.   I think I may hold some right rudder most of the time.   But can also correct with the knob on the TC that puts input into the wing leveler.

[N201MKTurbo]

You adjust a heavy wing by bending the trailing edge of the ailerons or adjusting the flap stops. If the rudder is out of trim you need to bend the trailing edge of the rudder.

The horizontal stabilizer being at an angle is very concerning. You need to get to the bottom of that. I would level the plane laterally by laying a level across the seat rails and adjusting tire pressure until the plane is level, then put a level on both sider of the horizontal stabilizer and the rudder. You need to get to the bottom of that before you do anything else. If you try to move the tip of the horizontal up and down, is there any play in it? there should be none.

[David Lloyd]

Should have been a little more specific.  Airplane level on ground, make certain the ball is truly centered.  I noticed on my airplane one wingtip was several inches higher from the floor than the other.  Several gallons of water later I could see the opposite main was sitting in a puddle, the other not.  Sloping concrete, wavey concrete, different tire pressures, more fuel on one side, different compression of the shock discs; a lot of things can affect measurement.

[Andy95W]

Twisting/moving/bending shit by unknowledgeable people is the reason so many Mooneys aren’t rigged right and fly crooked in the first place.  If done properly, your Mooney will fly straight regardless of fuel tank level and you’ll gain speed. Done wrong and it’ll get worse and slower.

You don’t say where you’re located.  It’s important.  We can recommend specific shops that will do the job right without experimenting.

[PT20J]

Shoptalk - rigging.pdf

[BillYesIAm]

2 hours ago, Andy95W said:

“You don’t say where you’re located.  It’s important.  We can recommend specific shops that will do the job right without experimenting.”

I’m at KMKS (Moncks Corner, SC), just north of Charleston.  I would love to get a good recommendation for a proper rigging job for my M20C. I have owned this plane for almost 17 years and it has never been particularly fast, always about 10 kn lower than book.

that PDF document was good but it would be nice if I did not have to go all the way to Wisconsin.  Thank you.

2 hours ago, Andy95W said:

 

 

[Andy95W]

That’s an easy one.  AGL Aviation in Morgantown, NC.  Lynn Mace and his wife run an excellent shop.  Lots of folks around here will vouch for them.  Schedule a day with them, they’ll get your M20C right.

https://aglaviation.com/agl-home

 

Edited December 19, 2021 by Andy95W

[BillYesIAm]

4 hours ago, Andy95W said:

That’s an easy one.  AGL Aviation in Morgantown, NC.  Lynn Mace and his wife run an excellent shop.  Lots of folks around here will vouch for them.  Schedule a day with them, they’ll get your M20C right.

https://aglaviation.com/agl-home

 

Okay Andy (and others who contributed to this thread). I will check out AGL Aviation.

I don’t want to veer too far from the original conversation, but I was wondering what fellow Mooney owners thought about the general credibility of shops that are certified Mooney Service Centers. In theory, shouldn’t they all be equally qualified to service any Mooney Aircraft? I am not going to name names but sometimes I wonder what exactly one has to do to acquire that certification?

[Guest]

Just like pilots, shops, maintainers and MSC’s, not all are created equally.

Clarence

[Prior owner]

Here ‘s what I like to do before starting any rigging job:

1. fly in the plane myself to confirm where it’s at before I touch it.

2. make sure the gear doors are closing completely and the step is retracing fully.

3.  If you’ve had any panel work done (such as a new G5), and the original turn coordinator has been removed, I like to level the aircraft per the manual to see whether the instrument‘s “ball” is calibrated properly.

4. closely examine the trailing edges for damage or evidence of having been bent for “rigging” by somebody else.
 

The aileron/rudder interconnect spring setup can also cause problems, and I have seen a number of aircraft where those springs are not rigged properly, or where one spring was more tired than the other. 
 

And remember, a Mooney won’t fly level hands off for very long, even after it is rigged properly!


 

[Prior owner]

9 hours ago, BillYesIAm said:

Okay Andy (and others who contributed to this thread). I will check out AGL Aviation.

I don’t want to veer too far from the original conversation, but I was wondering what fellow Mooney owners thought about the general credibility of shops that are certified Mooney Service Centers. In theory, shouldn’t they all be equally qualified to service any Mooney Aircraft? I am not going to name names but sometimes I wonder what exactly one has to do to acquire that certification?

I do not believe that there is a “certification” that is necessary to either become, or continue to be, a Mooney Service Center. If there is a certification to become one, there certainly must not be any requirement to re-certify over time, or when the business is purchased by a new owner, that you still have trained and qualified people in place. You can find yourself at an MSC that is run by someone who has limited, or no experience working on a Mooney, that has A&P’s who have never worked on a Mooney, and has non-A&P’s working on your Mooney…. Some of the more knowledgeable Mooney mechanics I have met don’t work for MSC’s. Choose wisely.

[Jim Peace]

8 hours ago, M20Doc said:

Just like pilots, shops, maintainers and MSC’s, not all are created equally.

Clarence

Understatement of the year.
 

If I don’t find a good close by  shop soon I am going to give up ownership for a while.  I have no problem paying large bills. There is just nobody who does quality work nearby. And forget about great communication. That’s a thing of the past. 

[RoundTwo]

1 hour ago, Jim Peace said:

 

Understatement of the year.
 

If I don’t find a good close by  shop soon I am going to give up ownership for a while.  I have no problem paying large bills. There is just nobody who does quality work nearby. And forget about great communication. That’s a thing of the past. 

Come on up to beautiful NW Georgia. There’s a great shop up here. You can buy cheap flooring products too. 

R2

[BillYesIAm]

5 hours ago, PilotCoyote said:

I do not believe that there is a “certification” that is necessary to either become, or continue to be, a Mooney Service Center. If there is a certification to become one, there certainly must not be any requirement to re-certify over time, or when the business is purchased by a new owner, that you still have trained and qualified people in place. You can find yourself at an MSC that is run by someone who has limited, or no experience working on a Mooney, that has A&P’s who have never worked on a Mooney, and has non-A&P’s working on your Mooney…. Some of the more knowledgeable Mooney mechanics I have met don’t work for MSC’s. Choose wisely.

I did not know that. Interesting. I always assumed that if it was an MSC then there would be at least one very experienced person with Mooneys. Thanks. I will be more careful in the future. I guess I need to log on here more often. Ha ha

[BillYesIAm]

5 hours ago, PilotCoyote said:

Here ‘s what I like to do before starting any rigging job:

1. fly in the plane myself to confirm where it’s at before I touch it.

2. make sure the gear doors are closing completely and the step is retracing fully.

3.  If you’ve had any panel work done (such as a new G5), and the original turn coordinator has been removed, I like to level the aircraft per the manual to see whether the instrument‘s “ball” is calibrated properly.

4. closely examine the trailing edges for damage or evidence of having been bent for “rigging” by somebody else.
 

The aileron/rudder interconnect spring setup can also cause problems, and I have seen a number of aircraft where those springs are not rigged properly, or where one spring was more tired than the other. 
 

And remember, a Mooney won’t fly level hands off for very long, even after it is rigged properly!


 

Thanks for the advice.

[carusoam]

Bill,

You are going to find….

That a small amount of research around here will help you find the things that are best for you…

Everyone is different…

When it comes to maintenance… it is the people inside the shop that are important… not the name on the outside of the shop…

Sometimes the name of the shop is the same as the people inside…

If your favorite MSC, has a presence here… you are probably in good shape…

If your favorite MSC avoids social media… it is more difficult to get to know their capabilities….

There are a few MSCs that stop by often… and one that lends a hand nearly every day…. 

Oddly, the best MSC has the name Tri-city on the outside, and Clarence on the inside…

 

There are also many experienced Mooney mechanics that have Mooney or MSC experience… in their résumé.

It comes down to finding the right people for the job…

 

Imagine needing an…

1) oil change

2) annual

3) replacing wing parts

4) Rigging… a few specific tools, plenty of Mooney experience… chance of getting it right without these, slim….

 

Some things warrant getting the best experience possible…

Best regards,

-a-

[Prior owner]

On 12/18/2021 at 5:46 AM, BillYesIAm said:

The left tip of the horizontal stabilizer is about 1.5 inches higher than the right tip. I have checked it a few times on level surfaces, first verifying levelness of the wings. Is this normal? If not, what might cause this? Also, could this have anything to do with the banking issue?

 

I forgot to mention one other thing- It is not all that uncommon to find the elevators are not equal (one of them 1/2 degree or more higher than the other) on the vintage Mooneys. This too, will give you a rolling tendency. Find an A&P who has travel boards and some experience sorting out a Mooney. And if you truly do have a horizontal stab that is not level, you should stop flying the plane until it is sorted out!

[BillYesIAm]

On 12/18/2021 at 2:48 PM, Yetti said:

Some of that is P factor.  My instructor showed me how to do the pattern turn to the left was just let up a little bit of right rudder you put in from takeoff.   I think I may hold some right rudder most of the time.   But can also correct with the knob on the TC that puts input into the wing leveler.

Yes, thanks, but I am talking about sustained level cross country flying, not pattern work.

[mike20papa]

On 12/18/2021 at 1:52 PM, N201MKTurbo said:

You adjust a heavy wing by bending the trailing edge of the ailerons or adjusting the flap stops. If the rudder is out of trim you need to bend the trailing edge of the rudder.

The horizontal stabilizer being at an angle is very concerning. You need to get to the bottom of that. I would level the plane laterally by laying a level across the seat rails and adjusting tire pressure until the plane is level, then put a level on both sider of the horizontal stabilizer and the rudder. You need to get to the bottom of that before you do anything else. If you try to move the tip of the horizontal up and down, is there any play in it? there should be none.

This is the most concise advice yet.  So, what is the movement/"play" in the horiz. stab?

[N201MKTurbo]

3 minutes ago, mike20papa said:

This is the most concise advice yet.  So, what is the movement/"play" in the horiz. stab?

The OP stated that his horizontal stabilizer was sloping side to side. The only way I can imagine that happening is being bent from some severe hanger rash or the pivot hinges are coming apart. If the pivot hinges are coming apart, the stabilizer could be moved by grabbing the left or right end and trying to move it up or down. It shouldn’t move at all, if it does, something is broke.