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Auto pilot roll servo

KTM520guy

Well Known Member
The nice UPS lady just dropped off my auto pilot today. Didn't take more than a second to open that box to have a peek at what was inside. It's a TruTrak Pictorial Pilot btw. It took me a few minutes to grasp what the drawings were telling me about how to mount the thing and how it works. Before I start mounting the thing I wounder if anybody has any pictures of the servo mounted under the seat?

Thanks,
:)
 
That's what came in the box with the auto pilot. I was kind of looking for an actual pic just to put my mind at ease.

Thanks,
:)
 
FWIW. Trutrak's instructions used to show the roll servo mounted on the left longitutinal floor bulkhead aft of the center section. If you have installed the aileron trim, the bracket for the servo interferes with the one for the trim. I called them and asked if there was any reason the servo couldn't be mounted on the right longitudinal bulkhead and they told me there wasn't. So I did it that way and it worked out fine.

You'll love the pictorial pilot! Been flying mine for 90 hrs. now and find it so useful it is seldom turned off. If you haven't installed the aileron trim yet you might consider skipping it. Any roll induced by unequal fuel burn is easily counteracted by the Trutrak.

John Miller
 
any pictures of the servo mounted under the seat?




If you have installed the aileron trim, the bracket for the servo interferes with the one for the trim.
Hmm. This may be installation specific, as I didn't have this problem. The TruTrak install kit was one of the few things on the airplane that required almost no head scratching for me.

I did have a very early kit, probably one of the first 50 or so, and they might have changed it somewhat. IIRC the whole thing took maybe 30 minutes on my QB fuselage, although there wasn't much else installed in that area yet, except the trim.

James Freeman
 
I just got finished with installing the Trutrak roll servo bracket yesterday. My installation looks just like James'. Acording to the Trutrak diagram, the bracket is supposed to be far enough aft so that it shares one of the rivets already in the floor rib. As James and myself found out, there is a stiffening bead in the floor rib that interferes with the bracket if you put it there. When I moved it forward enough to clear the bead, I had a little interference between the servo arm and one of the floor stiffeners. I ended up bending the stiffener a little bit in that area and problem solved. If you haven't done the floors yet, you should be able to rotate the stiffener 180 degrees and I think it will clear the arm.

The other minor gripe about the installation was the pitch servo brackets. I had already installed the brackets that I fabricated per Van's plans. I had to drill out the rivets and back drill through the holes in the baggage ribs. Not a huge undertaking, but it would have been a lot easier and cleaner if I had installed the servos much earlier in construction. Live and learn.
 
Another picture

Here is another picture. The nice folks at Tru Trak sent me the mounting brackets for my -8A free of charge (must of figured if I was installing their brackets I would eventially buy their auto pilot, they are right). I probably didn't hurt that my RV-6 has had a Tru Track installed for 3 years. I can't say enough good things on how well the thing works. Makes a great plane even better. The bracket for the aileron trim sent from Van's was way wider than the previous picture. I could have probably matched the flange of the trim bracket and the servo mount up. But without the servo and arm to check things out, decided not to match the flanges up. As you can see, the trim bracket overlaps the stiffner web of the rib - oh well. As far as the usefulness of the aileron trim, the one in my -6 works great and even with mostly negative comments from -8 owners, again decided to install it. Can't have the auto pilot engaged indefinately!

builderslog06021bn.jpg
 
TruTrak Roll Servo

I also mounted my roll servo on the right longitudinal rib, which is the opposite side of the aileron trim. It fit very well and offered no mounting difficulties. I also got the mounting kit and servos during my slow build fuselage framing, this allowed me to pick the control head I wanted once I designed the panel. By having the brackets and servos during the early phase of fuselage building, I was able to mount the servo in an ideal location. (in my opinion anyway). I inverted the bracket and placed it on the right rib.
I could get a picture if this does not make sense.

Cheers
FM
 
What's the other thing?

James, what's the other thing towards the aft in your picture? Looks like another servo...
 
backup autopilot

James, what's the other thing towards the aft in your picture? Looks like another servo...

It is another servo. I have a BMA EFIS-One, and it has an integrated two-axis autopilot. I was worried about having the autopilot connected to my primary attitude reference. When I was looking for a backup, the RC Allen gyros (pretty much the only thing available at the time) were getting harder to find, seemed to have longevity problems, and were susceptible to acro.

I reasoned that a wing-leveler tied to the battery bus (less than $1500 at the "introductory" price) was cheaper, and weighed the same or less as the RC-Allen gyro.

I have an "auopilot master" to switch between the two units. Either one flies the plane fine, although the BMA is smoother and has more features--the smoothness is probably because I've spent more time "tweaking" the BMA and just done the basic setup in the TruTrak.

James Freeman
 
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