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View Full Version : Dynon pitch with TruTrak roll


bigginsking
12-15-2008, 02:31 PM
Hey Folks:
I just installed a pitch axis only Dynon autopilot to compliment my Trutrak roll axis only pictoral pilot.

When I was building trutrak was the only game in town and I prewired for a trutrak pitch servo which I did to the point where the connectors with proper pinouts were installed and tucked away for when I wanted to spend 1500-2000 to be lazy and let a machine hold altitude. The pictoral pilot displays a turn and bank completely independent from the EFIS and is part of my redundancy scheme. In 330 hrs I became very used to flying on roll axis autopilot with my hand on the manual trip knob to hold altitude and as such I never saw fit to blow the cash.

Flash forward and dynon starts making noise about having an autopilot. After a few conversations with them I find out that I'll have to blow more than 1500 on 2 servos since theirs is different than the TT and I'll also have to rethink my redundancy scheme... Then I find out that you can just install a pitch servo for only about $800. Adding fuel to the fire AIG offers me a 10% discount for a "technically advanced aircraft" which with my existing other equipment(moving map, IFR cert GPS, fuel totalizer, terrain...) I would qualify for if I had a 2 axis autopilot... so in the typical aviation fashion I saved $200 by spending $800.

The install was pretty easy, I was able to bridge both the control wheel disconnects into the one existing switch with no adverse effects. One long button press engages roll and pitch, slightly shorter and you get roll only, short disengages both. Since I was leveraging off my trutrak pre wire the wire I used to the servo(DSAB included) was not twisted pair as they recommend but it still works fine. I took a short flight this afternoon and it seems to work fine but I'll need to do some cross country to really get a feel for it. I've see some posts on Vans Airforce complaining of an install that oscillates in pitch with growing excursion magnitudes. If this is the case they should be able to fix it with a firmware upgrade.

Bill Judge
N84WJ
330 Hrs.

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