PC Control System Troubleshooting

[Flybeech21]

The PC Control (Wingleveler) has been INOP since I have owned my 1966 M20C.  I just started an inventory of the system and all components are installed and hooked up but the aileron and rudder servos are disconnected.  After a quick look at all of the servos, a couple of them have holes in the diaphrams. There are a couple of lines that appear to be rotten and need replacing as well.  I am sure the filters will all have to be replaced.

Should I just remove the components and send them to Brittain Industries to have them all overhauled before I start testing the system or should I just replace the servos that have holes and go from there?

I figured the Rate Gyro would definitely have to be replaced after sitting idle for years but, after learning that the gyro has been spooling up all this time I am giving that a second thought.

Any one have experience tinkering with this system???

[MooneyMitch]

Hi Kevin.

I suggest replacing the boots........easy to do.  Revmove the servos, remove the old boots, clean the cannisters and install the new boots using electrical tape........probably 2" wide or so.  Easy to replace the lines too.  The hardest part is access to the lines in the cabin area.  You'll have to remove some side panels...........you CAN do it yourself. 

Check the servo boot in the tail as well.  If you have the vacuum operated step, check that one for replacement too.  I don't recall where I purchased the new rubber boots for the servos.  Check LASAR, Don Maxwell and Southwest.  If they don't have them, more than likely they will point you in the right direction.  It is a very simple system. 

 

[Seth]

I had my PC system fixed during my last overhaul (boots, gyro) and for not a lot of cash its a VERY useful system.  Helps with IFR flying, IMC, Cross Country, heck, any type of flying.

However, if you pull the button up to disconnect the system too often, you can damage the fitting.  Instead, get a thick rubber band (and have a spare, they snap at the most inopportune times) and simply wrap the disconnect button down during takeoffs and landings.  That way you don't have to have your thumb depressing the disconnect in the pattern (and making calls at the same time to the tower or unicom).

The PC wing-leveling system just makes the Mooney that much more of a stable aircraft.  I highly reccomend it.

[MooneyMitch]

For our flying with the PC system, it just became a habit to put that thumb up and hold the button in the depressed position during turns.  Whether that be during cruise, landing or takeoff modes.  Any other time, the PC system was actuated.  Our PC release button is located on the upper left hand area of the pilot yoke.  In my opinion, the PC Wing Leveler system is an excellent tool.

[Flybeech21]

I spoke with Brittan Industries and they informed me about the B-11 addition to the PC Control system.  it allows you to track a course in HI and Lo sensitivity and make standard rate turns.  The cost for the upgrade is $981.75.  That is is heck of a lot better than installing an STEC. 

Seems like an inexpensive and feezable alternative to a very expensive autopilot upgrade.

I cant seem to figure out how to attach the brochure so, if anyone wants it I can email it to you.

 

Here is the website for Brittain Industries.    

http://brittainautopilots.com/

 

 

[Lood]

I had a look at Brittain's website a while ago and was quite surprized by their prices - to such an extend that I considered having one of their systems fitted. When I mentioned it to a local AME, however, he informed me that Brittain auto pilots were not TSO'd for installation in certified aircraft. I left it at that, but it has been bothering me since. If early Mooney's were, and some still use,  Brittain's PC wing leveller system, it definately has to be certified. Or is the PC system the only one of their systems that are certified?

I would appreciate the correct facts on Brittain's systems.

[Flybeech21]

Quote: Lood

I had a look at Brittain's website a while ago and was quite surprized by their prices - to such an extend that I considered having one of their systems fitted. When I mentioned it to a local AME, however, he informed me that Brittain auto pilots were not TSO'd for installation in certified aircraft. I left it at that, but it has been bothering me since. If early Mooney's were, and some still use,  Brittain's PC wing leveller system, it definately has to be certified. Or is the PC system the only one of their systems that are certified?

I would appreciate the correct facts on Brittain's systems.

[KSMooniac]

You can most definitely install one of their systems into your Mooney.

[eaglebkh]

Just curious, how do those of you with the PC system allow someone in the right seat manipulate the controls (i.e. during dual time for unusual attitude recovery, IPC, BFR, etc.)?  Strap down the interupt switch?

[Seth]

Yes, you strap down the button with a rubber band, or some other contraption (the old 35mm film container from JimR sounds like something I may try).  You can also pull the button up, but again, that can lead to breaking the seal if overused.  A rubber band works with out a problem.

I talked to my mechanic and a system on/off button can be installed somehow, but the cost invoved would be $1500 or greater.  I say a rubber band works just fine.

[Hank]

I fly with my PC all the time, and rarely even press the override button. In the pattern, the extra stiffness keeps me from accidentally overbanking. I do have to hold it down for right-seaters to maneuver, though.

I use the Accu-Trak and Accu-Flite--the heading bug almost all the time, the auto-pilot much less. Both work well, and are certified for my '70 C.

 

[mjc]

Quote: eaglebkh

Just curious, how do those of you with the PC system allow someone in the right seat manipulate the controls (i.e. during dual time for unusual attitude recovery, IPC, BFR, etc.)?  Strap down the interupt switch?

[HRM]

Quote: Seth

Yes, you strap down the button with a rubber band, or some other contraption (the old 35mm film container from JimR sounds like something I may try).  You can also pull the button up, but again, that can lead to breaking the seal if overused.  A rubber band works with out a problem.

[Seth]

My guess is its just the O-Ring, but the MSC I have the plane worked at warned me against pulling it out like that.  They said if the system is malfunctioning, do that as a last resort in order to not have to fight the controls, otherwise press it with your thumb, or just get a rubber pand to act as the thumb.  If its just an O-Ring, great, but who knows what the $$$ may be if its not reinstalled correctly, or if there is a leak of some sort.  Again, my suggestion, get a thick rubber band, and just use that. 

The MSC is Freeway Avaition in Maryland, call them up and they'll chat with you about it.  www.freewayaviation.com

 

[HRM]

Quote: Seth

My guess is its just the O-Ring, but the MSC I have the plane worked at warned me against pulling it out like that.  They said if the system is malfunctioning, do that as a last resort in order to not have to fight the controls, otherwise press it with your thumb, or just get a rubber pand to act as the thumb.  If its just an O-Ring, great, but who knows what the $$$ may be if its not reinstalled correctly, or if there is a leak of some sort.  Again, my suggestion, get a thick rubber band, and just use that. 

The MSC is Freeway Avaition in Maryland, call them up and they'll chat with you about it.  www.freewayaviation.com

 

[Carl S]

Quote: HRM

...Think about it, by holding that button in all the time you are giving the spring a bad memory.

[Seth]

Mike at Freeway is great - glad you got a chance to talk with him.  Tommy, Mike, and Bruce I would trust with any Mooney issues whatsoever.

I contacted Brittain last night with an email and they came back to me today with basic costs, my different options, and asked me if I wanted to be added to the eight month wait list (confirmed from earlier in this thread).  I said yes, and will probably add a system (not sure which one yet).  PM me with your email and I'll send over the attachments they sent me.

[HRM]

Quote: Seth

Mike at Freeway is great - glad you got a chance to talk with him.  Tommy, Mike, and Bruce I would trust with any Mooney issues whatsoever.

I contacted Brittain last night with an email and they came back to me today with basic costs, my different options, and asked me if I wanted to be added to the eight month wait list (confirmed from earlier in this thread).  I said yes, and will probably add a system (not sure which one yet).  PM me with your email and I'll send over the attachments they sent me.

[georgeb]

From what I understand, the PC system IS approved for installation in our mooneys so TSO or STC'd should not be an issue with those of you worried about it. I believe that there is no field approval for it so it may have to be installed at Brittain. I'll check on that tomorrow and find out, but I for one am on the list as one who will be upgrading the factory PC wing leveler from Mooney/Britain.

As for pulling the button out, There are three other mooney's that belong to buddies of mine here in KELP and they all either pull it out partially (as I do, about 1/4 ") to disable it, or remove it alltogether during takoff and landings. All of us do it with our A/Ps blessing and he's been flying mooneys (not just fixing them) longer than he cares to remember.

About flying from the right side, the system can be overridden even while it's engaged, it's just a little hard to do but you can still steer. As an added to the TSO STC question, two of the afore mentioned mooneys have the full autopilot systems in them. Both of theirs track heading as well as hold altitude and I can tell you from flying with them, the systems work great which is why I've decided to add to my system and upgrade to the full out autopilot.

George

 

[Flybeech21]

I just checked the Mooney Type Certificate and there is no mention of a PC control system or of Brittain.  That is pretty weird when the airplane was originally equiped with this system.

[GeorgePerry]

I use the brittan system and like it, but I do pull the over-ride button out for take offs and landings.  Put it in the very clean ash tray adjacent to the yoke.

[georgeb]

Quote: Flybeech21

I just checked the Mooney Type Certificate and there is no mention of a PC control system or of Brittain.  That is pretty weird when the airplane was originally equiped with this system.

[HRM]

Quote: georgeb

From what I understand, the PC system IS approved for installation in our mooneys so TSO or STC'd should not be an issue with those of you worried about it. I believe that there is no field approval for it so it may have to be installed at Brittain. I'll check on that tomorrow and find out, but I for one am on the list as one who will be upgrading the factory PC wing leveler from Mooney/Britain.

As for pulling the button out, There are three other mooney's that belong to buddies of mine here in KELP and they all either pull it out partially (as I do, about 1/4 ") to disable it, or remove it alltogether during takoff and landings. All of us do it with our A/Ps blessing and he's been flying mooneys (not just fixing them) longer than he cares to remember.

About flying from the right side, the system can be overridden even while it's engaged, it's just a little hard to do but you can still steer. As an added to the TSO STC question, two of the afore mentioned mooneys have the full autopilot systems in them. Both of theirs track heading as well as hold altitude and I can tell you from flying with them, the systems work great which is why I've decided to add to my system and upgrade to the full out autopilot.

George

 

[Flybeech21]

Quote: georgeb

 I have all the opriginal documentation for my '70 'E', including the original sales documentation and it includes all of the Britain documentation as part of the packet. Don't know about the STC, but I guarranty you mine came from the factory with it installed!

George

[Flybeech21]

Removed all of the PC control system components and shipped them to Brittain on Friday.  They said they will bench check everything before recommending which parts to be overhauled.  Looks like I am going to get my poor mans autopilot back online for less than an AMU...

Guess I should wait for the bill before I get excited..