PC control or Rigging?

[Espeed]

 Hey guys, I am new to the Mooney world some what, I grew up flying in my fathers mooney's but now I own my own.  Last month I purchased a nice 1965 M20E and I absolutley love it, The biggest issue that I have is during level flight she wants to bank to the right really hard, I have to hold the left aileron up just to maintain level flight.  Now as far as the PC control is concerned, I am not sure if it even works, the panel has been updated to a 201 style panel and the yokes are the 201 style as well but right over the throttle control is the roll pitch knob and the pull knob for the PC control.  The only button on the yoke is the transmit button, I have pulled the PC knob out and pushed it in and I can't tell any difference in the flight characteristics.  My question is, has anyone had this problem and could it be a rigging issue.  I did notice that if you hold the left aileron level with the left flap that the right aileron is about a quarter of an inch higher than the right flap.  Are the ailerons out of center or do the flaps need to be adjusted.  Any Info would be great.

Thanks,

Steven

 

[N601RX]

When I first got my plane the PC would not turn off and it pulled to one side. It turned out that 2 of the vaccum hoses under the dash were crossed. The plumbing schematic and troubleshooting info is in the mooney service manual.  Here is a link to the troubleshooting manual.  Brittain is also helpful if you call them. There is also several slight variations of this system so be sure you are looking at the correct one.

http://www.67m20e.com/Manual%20No.%2011990%20Mooney%20PC%20Operation%20and%20Service%20Instructions.pdf

[N601RX]

When I first got my plane the PC would not turn off and it pulled to one side. It turned out that 2 of the vaccum hoses under the dash were crossed. The plumbing schematic and troubleshooting info is in the mooney service manual.  Here is a link to the troubleshooting manual.  Brittain is also helpful if you call them. There is also several slight variations of this system so be sure you are looking at the correct one.

http://www.67m20e.com/Manual%20No.%2011990%20Mooney%20PC%20Operation%20and%20Service%20Instructions.pdf

[carusoam]

Definitely search for rigging issues on this site.  There are a couple of methods of eyeballing the common rigging issues.

I have two thoughts that may help troubleshoot your issues.

[1] What happens when you burn the fuel out of the "heavy" side.  Do things try to even out?

[2] The 65 C had the PC gyro next to the vacuum step.  The E is probably in the same place.  When you shut down, you should be able to hear the gyro winding down slowly and smoothly.  Does your gyro sound right?

Best regards,

-a-

[Espeed]

No, it still banks to the right with full fuel, the last flight i flew 1 hour on right tank, then returned on the left tank, it still wanted to bank to the right with the left side being heavier.  The gyro sounds like it is supposed to, you can hear it winding down slowly after shut down.  Nothing abnormal about the way it sounds that is catching my attention. 

[N601RX]

My F uses the Turn cordinator gyro in the panel.  Some others have the gyro mounted in the back. The gyro has 2 vac lines.  One to spin the gryo and one to provide vac to the pc system.  The one to the pc system should be routed disconnect valve. I would have it temporary removed and capped and see how it flies. 

[richardheitzman]

it would be fairly easy to check the rigging on the elevators and alierons. Go to a Mooney service center in your area and let them put on the travel boards. That will tell you if it is out of rig.

If you have confirmed that everything is good, ask them to help you look at the PC system

Good Luck

Richard

 

[Hank]

I hate to sound like a smartass, but I'm starting to dig into my own PC issues that I originally thought were from my Brittain heading bug. Found some good information in the Service Manual, Section 6, complete with locations of servos, valves, hoses, etc., and a diagram of the whole mess. Hopefully it will help.

Do you have access to the Service Manual for your aircraft?

[takair]

Does the yoke turn hard right on the ground when the vacuum reads in the green?  The preflight for the PC is:  taxi turn left-yoke should turn right, taxi turn right-yoke should turn left.  If with vacuum yoke pulls right all the time then you may have a leak.  If it stays level and moves as easilly as with no vacuum then you have an inop PC and probably have rigging problems.  You shoudl have a PC disconnect button on the yoke.  Sounds like your PC may be disabled. 

[Espeed]

This friday I am going to check to see if the PC is working during taxi, Once again, I don't have the original yokes and panel in my plane,  It has the 201 style panel and yokes.  The PC turn on is a pull knob mounted right above the throttle control and right next to it is the roll trim knob.  The PC knob sais "Pull On" on top of it, It stays in the off position all the time, I have tried flying with it in the off position and the on position and I can't feel any difference in the yoke tension, the plane still wants to pull to the right no matter what.  I am also going to check the position of the left flap as well, It may need a little adjusting, either way I am going to have it seen about as well as having my PC system look at thoroughly.  Thanks for all the responses, It has helped greatfully.

[Espeed]

Quote: takair

Does the yoke turn hard right on the ground when the vacuum reads in the green?  The preflight for the PC is:  taxi turn left-yoke should turn right, taxi turn right-yoke should turn left.  If with vacuum yoke pulls right all the time then you may have a leak.  If it stays level and moves as easilly as with no vacuum then you have an inop PC and probably have rigging problems.  You shoudl have a PC disconnect button on the yoke.  Sounds like your PC may be disabled. 

[kerry]

The way you described your flaps and ailerions I would say you need rerigging. 

[takair]

Quote: Espeed

 Takair, noticed that you were from Richmond Hill,  I am going to be flying in to Hinesville Sat. to drop my wife off to visit a friend there at Ft. Stewart and will be picking her back up on Sun.  Which airport are you based at and are there any other good places to fly in to close to Savannah other than Savannah Int.  I have a few friends in the Savannah area and wouldn't mind flying there to visit them but would rather avoid the class C airspace.

[Espeed]

UPDATE!!!!

Ok guys, This is what I learned, come to find out, my left flap was indeed slightly lower than the right flap, I adjusted the set screw on the outer hinge of the left flap to the best eye sight of the other flap (about three turns on the screw) and then flew it on a short trip Friday afternoon.  Man what a difference, she flys hands off and perfect now, the PC works great, I flew with it on going there and coming back and it worked just like it was supposed to.  My best guess is there was too much force from the flap that the PC couldn't over come it but now that it flys level, it works great.  It is like flying a whole different plane. Thanks to everyone for the responses and help.

[airkraft]

Glad to hear a success story, E.

We picked up over 10kts IAS by fine tuning aleron, elevator and especially rudder rigging using factory jigs and specifications.  See previous posts for details.  Highly reccomend doing so at each annual! 

 

[flhelo]

Good to hear that you got it resolved!!