Restore or remove Accu-Trak B11

[christaylor302]

I’m restoring a ‘66 M20C with an Accu-Trak B11 installed. However the vacuum system is a mess and I don’t know if any of the Accu-Trak components work. It looks like some of the vacuum lines were cut away.

 

I’m trying to decide if I should attempt to restore the Accu-Trak system, or remove it and the vacuum system.

 

Maybe I try putting together a STEC system in the future?

 

I plan on mostly VFR and some light IFR when required.

 

I know there will be opinions on both sides, but I’m interested in hearing any suggestions or experience.

 

How does a M20C handle without the Accu-Trak or PC system?

 

I’m trying to keep the first wave of expenses within reason (LOL). This will not be an all Garmin glass plane.

 

Thanks,

Chris

[Greg Ellis]

4 hours ago, christaylor302 said:

How does a M20C handle without the Accu-Trak or PC system?

 

I have a 63 C model.  It came without any PC system, wing leveler, or anything.  I have owned this airplane for 17 or 18 years now.  For about 14 years I hand flew (no autopilot) IFR sometimes to minimums.  The airplane is very stable without an autopilot if well rigged and trimmed well.

I now have a Garmin GFC 500 and love it but the plane did very well without any autopilot.

[KSMooniac]

You won't be able to legally install a used STEC and I don't believe any of the available models new are certified for a C. The old TruTrak now Aerocruz might be an option and a frugal choice.

I have no experience but have read many times that the Brittain/PC system is simple and reliable when the components are working and there are no leaks. Troubleshooting the vacuum lines is straightforward. There is no support that I'm aware of to rebuild or overhaul components, but I have seen steady availability of take-out parts since owners are upgrading.

A working PC system, especially with a working Brittain autopilot, would be way better than nothing IMO. If you're able to scrounge parts and install/troubleshoot yourself versus paying for that labor, it might be a good option. Or you could get dozens of hours into it and find you're missing something, or can't get a component fixed.

The Aerocruz can be installed by an A&P/IA and potentially by an owner with supervision if so inclined. All of the parts will be in a box with instructions and support. It will work, and it will make the plane easier to sell in the future too.

If the plan is not to fly long trips anywhere, then I would skip all of the options, but Mooneys are meant to travel and IMO should have at least a basic AP for those long days.

Sent from my motorola edge plus 2023 using Tapatalk

[BrianWilkins]

“Light IFR” without an AP is fine in my opinion and I did quite a bit of that in my E before I got a new panel. I don’t think you’d want to do hours and hours of IMC without one though. Trying to get the old Britain system working is probably going to be next to impossible based on my attempts. Only real option right now is Garmin because Dynon and others just aren’t interested in certifying for the older models. The Garmin is incredible but very, very expensive. 

[LANCECASPER]

1 hour ago, BrianWilkins said:

“Light IFR” without an AP is fine in my opinion and I did quite a bit of that in my E before I got a new panel. I don’t think you’d want to do hours and hours of IMC without one though. Trying to get the old Britain system working is probably going to be next to impossible based on my attempts. Only real option right now is Garmin because Dynon and others just aren’t interested in certifying for the older models. The Garmin is incredible but very, very expensive. 

@cliffy installed an Aerocruze 100, so there is another option.

 

[cliffy]

I have posted here on MS my experience with the AeroCruze 100 (TT)  autopilot.

I installed it as an A&P  No "approved" shop required for the install. 

It works fine in my D model for a basic VFR A/P and light IFR. It will do GPSS if wanted.

Install is not difficult. Has "one button push" for straight and level flight great for inadvertent IMC.

I removed a working Accutrak for the A/C 100. Much happier with the A/C 100.

Can;t beat the price (in a Mooney) for a working A/P  The choices are very limited. 

If you want a good A/P for a VFR Mooney ( or light IFR) go Aerocruze 100

If you do heavy IFR to mins all the time spend the money on Garmin  $$$$$$$

LANCECASPER  was writing as I was typing :-)

[Utah20Gflyer]

Unless you can do all of the work yourself and don’t mind spending the time to do it the Brittian system is not going to be cheap to fix.  It would be more cost effective I think to install the Aerocruze auto pilot.   I worked on my PC system some when I first bought my plane but kept having problems and eventually ripped out everything including the vacuum system.  The PC systems in our planes are 50+ years old, if you want it to work properly it’s probably going to require replacing and rebuilding everything in the system.  Not worth it in my opinion.  If I had a system that worked I’d run it until it stopped working but not worth the investment in time and money to rebuild it.  
 

A Mooney flys great without an autopilot.  I’d say as good or better than any other light airplane.   That being said I’d still like one and plan on getting one in the next couple of years.  

[Vance Harral]

We have a fully working Brittain PC/B-5 system, and it's nice for what it is (75-year-old technology).  But at this point, I think the question of resurrecting a non-working Brittain system has less to do with cost and workload - which are manageable - and more to do with the availability of mundane parts: vacuum lines, servo boots, etc.

http://www.brittainautopilots.com/  is still online with a listed phone number, but it's my understanding that people who have recently tried to obtain parts either never get a response, or get a response that the company is "in limbo" with little or no legal ability to actually make parts.  That leaves salvage items, kludge fixes, and under-the-table deals, which is a frustrating scenario for an aircraft owner.  It is not difficult to debug why the system isn't working, but once you identify the problem(s), you may find it difficult to resolve them in a satisfactory manner.  In our case, we have a small cache of spares, but maintaining the system has begun to feel more like maintaining a warbird than a certified airplane.

[DCarlton]

Like many have mentioned in other PC related posts on Mooneyspace, Kevin Westbrook is the remaining most knowledgable person regarding the Brittain Autopilots.  He's a member here.  If you decide to troubleshoot or restore, he should be able to help even if over the phone.  He's helped me keep mine operational.  As a mechanical engineer by degree, and someone who loathes software updates, it's a design I still admire.  There are schematics available if you wanted to start with basic troubleshooting and check your vacuum lines and servo boots for leaks.   

https://mooneyspace.com/profile/48565-kevin-westbrook/

[Kevin Westbrook]

Chris Kevin Westbrook here I worked at Brittain call me 539-292-0474 and we can talk about the system!!!!

[Greg Ellis]

@christaylor302 ^^^^^^^^^ see above

[Echo]

Servos are still available on Ebay.  The controller is also available on Ebay.  I just say a B5 listed for very reasonable money.  It's just plastic tubing and rubber tubing you can get off of Amazon.  I am very pleased with my Accu-Flite install.  It was like 1500 parts and labor to get a heading bug auto pilot in my plane.  I did thee B5 and plumbing myself.  Pretty straight forward stuff.  My servos look great at 60.  Better than me for sure.

[takair]

Kevin is THE man. Almost all parts can be restored or found. Most pop up on eBay. Only Pegasus is the altitude hold servos if you have that system but I’m convinced there is an answer for that. I have a bunch of spare parts I’ve accumulated, just haven’t had time to organize and post them….if Kevin can’t fix it he knows where to find me. As others have indicated the biggest investment is your time and a willing AP who will allow owner assist or hangar else with the right attitude. 

[christaylor302]

I appreciate everyone's responses. This is all great information.

I did have a great call with Kevin yesterday. So much knowledge and just a really nice person. Thank you taking my call Kevin!

I've decided I'll take a wack at restoring the system. I do need the trim valve in the yoke, it's missing, and at least one aileron servo/boot. I still need to test the rest of the system to see if the other boots are ok. But if it becomes a PIA, I won't worry about just removing the system and going without. Maybe an Aerocruze 100 is in the future .

Thank you everyone!