M20C flight control rigging travel boards in PHX?

[EricShr]

Hi, anyone in the PHX area have a set of set of Mooney flight control rigging travel boards that I could rent or borrow? My M20c is wanting to roll to the Right with hands off in level flight WOT. I finally had enough with the old Brittain autopilot pulling to the right (never found the vacuum leak) - so I disconnected the aileron servos, but it is still pulling to the right and is obviously out of rig.

In flight, the the right aileron appears a degree or so higher than the left when compared to the flap.

[N201MKTurbo]

Hay doc, Travel boards won't fix your heavy wing. The heavy wing is caused by differential lift of the wings. you can fix a heavy wing by adjusting the flap stops or trimming the ailerons. I can give you a hand with that if you like.

[EricShr]

Hi, I might just need a hand with that rigging. Still have not gotten to the biscuits, as my autopilot died along with some other frustrations!

Aircraft has a right roll tendency which can be stopped with a very slight Left rudder pressure at cruise - to get ball in the exact center. If I correct with just aileron, the ball is just ever so slightly out of center to the Left. You might be on to something with the flap stops.

[N201MKTurbo]

  On 6/26/2023 at 2:34 PM, EricShr said:

Hi, I might just need a hand with that rigging. Still have not gotten to the biscuits, as my autopilot died along with some other frustrations!

Aircraft has a right roll tendency which can be stopped with a very slight Left rudder pressure at cruise - to get ball in the exact center. If I correct with just aileron, the ball is just ever so slightly out of center to the Left. You might be on to something with the flap stops.

Expand  

So we need to trim the rudder a bit and then maybe the ailerons. We will have to make a few flights to get it right.

[N201MKTurbo]

The flap stops are the easiest thing to do and don't cause any permanent deformation of the ailerons. If it takes too much flap adjustment and the flaps and ailerons look all cattywampus, you will have to trim the ailerons to get everything straight. In most cases the flap change is not visible.

[cliffy]

In flight both of my aileron balance weights are faired with the wing tip and they also match the level of the flaps 

I have a slight amount of left rudder trim on the trim tab for the very slight right turn tendency that I had. Ball not centered then. 

Had to adjust the aileron rods to get them faired with the wing tip in flight with flight loads applied then adjusted the flap stops to bring them level and then readjust the flap stops slightly to get straight and level roll trim.

[Fly Boomer]

  On 6/27/2023 at 2:24 AM, cliffy said:

In flight both of my aileron balance weights are faired with the wing tip and they also match the level of the flaps 

I have a slight amount of left rudder trim on the trim tab for the very slight right turn tendency that I had. Ball not centered then. 

Had to adjust the aileron rods to get them faired with the wing tip in flight with flight loads applied then adjusted the flap stops to bring them level and then readjust the flap stops slightly to get straight and level roll trim.

Expand  

Did all that just make it fly straight, or did you get a little additional speed as well?

[cliffy]

I got a slight amount of speed increase (maybe 3 kts) as I was close anyway. 

It flies hands off with very little roll  

I get almost book speeds  135 to 140 kts at 9500 WOT, 2500 and ROP 50-75. And my CG is fwd in the box which does make some speed loss due to drag trying to keep the nose up. In playing with CG many years ago it seemed to make a difference in speed in mine. 

I would like to drop a wing board on mine to see if my guess is close to what the travel board says O deflection should be. 

I've heard that a couple degrees up (flaps and ailerons) may increase speed also but I've flown it this way for 25 years and all seems very comfortable to me. 

[Jsno]

The travel board is a good starting point.  The Mooney I have had been rigged with the flaps rigged to roll one way and the ailerons to roll the other way.  This creates unneeded drag.  If you can locate some boards I would start there.

 

[Kelpro999]

Someone just bought a full set on eBay, wondering if it was a member?

[BDPetersen]

I keep hoping in light of the horrific prices the boards go for someone will develop a well thought out rigging procedure using digital levels/protractors.

[EricJ]

  On 6/29/2023 at 11:26 AM, BDPetersen said:

I keep hoping in light of the horrific prices the boards go for someone will develop a well thought out rigging procedure using digital levels/protractors.

Expand  

That's what many people already do, since the boards are just not available everywhere.   The rigging procedure in the SMM can be performed using a potractor or level instead of boards.   The travel settings are in the TCDS, so one could even do it without the SMM if necessary.

[Kelpro999]

  On 6/26/2023 at 1:07 PM, EricShr said:

Hi, anyone in the PHX area have a set of set of Mooney flight control rigging travel boards that I could rent or borrow? My M20c is wanting to roll to the Right with hands off in level flight WOT. I finally had enough with the old Brittain autopilot pulling to the right (never found the vacuum leak) - so I disconnected the aileron servos, but it is still pulling to the right and is obviously out of rig.

In flight, the the right aileron appears a degree or so higher than the left when compared to the flap.

Expand  

I have the aileron/flap board here in San Diego if you want to head west. 

[Tackleberrt]

  On 6/26/2023 at 1:07 PM, EricShr said:

"My M20c is wanting to roll to the Right with hands off in level flight WOT. "

Expand  

Mine does this too.  I'd love to know how you come out. 

[EricShr]

Hi Folks, so I have obtained the travel boards and found that my right aileron is 2 degrees high (-2.0) when compared to the flap (which is set at "0") - explains my right roll tendency.

So, from what I understand, in order to "adjust "the heim joint length (retract 1 turn?) at the bellcrank (to deflect the aileron downd 2 degrees), I must first unfasten the distal heim where it attaches to the aileron, and unfasten the heim in the belly in order to rotate the bellcrank / get access to the vertical thru bolts holding it at the bellcrank.

OR can I access the locknut on the heim attached to the bellcrank (thru the wing access panel while everything is still attached) and loosen the aileron rod in the belly and just turn it (1 turn in ) to pull the aileron "down 2 degrees"?

Richard - I got the shock discs finished!!!

[Kelpro999]

  On 7/16/2023 at 1:33 PM, EricShr said:

Hi Folks, so I have obtained the travel boards and found that my right aileron is 2 degrees high (-2.0) when compared to the flap (which is set at "0") - explains my right roll tendency.

So, from what I understand, in order to "adjust "the heim joint length (retract 1 turn?) at the bellcrank (to deflect the aileron downd 2 degrees), I must first unfasten the distal heim where it attaches to the aileron, and unfasten the heim in the belly in order to rotate the bellcrank / get access to the vertical thru bolts holding it at the bellcrank.

OR can I access the locknut on the heim attached to the bellcrank (thru the wing access panel while everything is still attached) and loosen the aileron rod in the belly and just turn it (1 turn in ) to pull the aileron "down 2 degrees"?

Richard - I got the shock discs finished!!!

Expand  

Do you own the travel boards?

[Kelpro999]

  On 7/16/2023 at 1:33 PM, EricShr said:

Hi Folks, so I have obtained the travel boards and found that my right aileron is 2 degrees high (-2.0) when compared to the flap (which is set at "0") - explains my right roll tendency.

So, from what I understand, in order to "adjust "the heim joint length (retract 1 turn?) at the bellcrank (to deflect the aileron downd 2 degrees), I must first unfasten the distal heim where it attaches to the aileron, and unfasten the heim in the belly in order to rotate the bellcrank / get access to the vertical thru bolts holding it at the bellcrank.

OR can I access the locknut on the heim attached to the bellcrank (thru the wing access panel while everything is still attached) and loosen the aileron rod in the belly and just turn it (1 turn in ) to pull the aileron "down 2 degrees"?

Richard - I got the shock discs finished!!!

Expand  

Is the left flap position ok?

[Andy95W]

@EricShr- please listen to M20Doc.  He knows what he’s talking about.

If you adjust your aileron the way you describe, your ailerons will still find their aerodynamic balance, you’ll still have a right roll tendency, but now your yokes will be crooked also.

[N231BN]

The first thing to check is to make sure the instrument panel is level and not sagging on loose shock mounts. The ball will only be accurate if the panel is level.

As others have said, you can't pick up a heavy wing with aileron rigging, many have tried and it always results in a crooked yoke.