A/P and Dynon servos
FYI to builders...pondering servo size (strength) when installing their autopilot system. I have a STOL 750 with two axis autopilot ( Dynon SV-32 servos.) During my 40 hr test phase I was having problems getting the autopilot pitch servo to not slip - esp. in turbulence. Went thru the whole setup routine per Dynon, but no joy, airloads were too much for the servo as the A/P worked to maintain selected altitude in anything but smooth air. Even then, in smooth air, during prolonged turns, the…See More
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David, I saw that you are interested in Datum skis. I have been flying with the skis for 4 years and am very satisfied with them. If you have any questions forward them to me and I will be gald to answer the best as possible.
Tom
You asked what we were seeing with the bad injector. The above is typical. #3 cylinder just was "not tracking" with the others.
Digging a little deeper, it is a bit hotter than others at idle (lean, where everything should be very rich), gets even hotter if the power is up only a tiny bit (even leaner), and actually "goes cold" when the power is advanced anywhere above about 1500 RPM, because it gets so lean it is not burning. Too lean for the plugs to ignite.
And... we thought this was a bad injector for a long time. After chasing down similar problems several times, we came to the conclusion the injectors were fine... that the ECU had an inadequate ground.
Conclusions:
First, check that all EGTs and CHTs "Track" each other in ALL conditions before first flight.
Second, check for very, very, very good grounds in an airplane that is so dependant on electronics. DO NOT count on the frame. Strap and/or "Star" (i.e. home run wires) everything.
Feel free to ask questions.
P.S. Graphs produced from Dynon logs via custom software that I wrote. Feel free to send me a log file if you want it graphed.
danal (dot) estes (at) gmail (dot) com
David,
You can reach me about the charger at ksatter@Verizon.net ... I can get it off to you by Monday.
Hi David. Hey, need to ask you about your experience with the Skytek tank. I talked to Keith at Skytek and watched the Rotax videos and am impressed with the product. Not impressed with the price and not sure about the 1 gal capacity. They say 7 and half minutes at full power for a Rotax engine if you are down to just the header. Assume then for a UL it would be about half that. I plan on a UL350is. I have seen the pics on your installation but do you still think this tank is the way to go?
David, too funny, I happened to zoom in on your dog because I kept thinking he really had a short muzzle for a German shepherd, and he looked like a cool mix………..then I saw someone stole his legs…… Pretty cool dog, purebred? I don't see many out here with shepherd markings like that.
Walt Snyder
nice to here from you Dave your welcome to stop in anytime.
Our goal is to move project to Caribou this spring for assembly, and begin testing by November.
Your postings show fine work and great progress; the State of Maine is a great match for the 750 performance.
Hi David,
Looking good ! Keep up the good work...It will eventually FLY...and well too !
Regards,
Norm
sure its convenient just let me know when you will be coming through.
Merry Christmas to you too
Kit building a 601XL since 2008 goal is to have it complete by this spring.
could use the material from the crates for your bench, its usually good straight material.
goes without saying but take the time to make it perfectly level, mine sat on metal saw horses and was 4 by 14.
air riveter is a really good idea, and air drill if compressor is large enough with #20 and #30 bits probably ten each to start i got mine at Fastenall in Presque Isle and they can get mil spec hardware too, you will need a torque wrench that reads in inch pounds.
when de-burring holes us a file, i used a drill bit and it chamfers as much as it deburs.
i have an acquaintance in Turner who has built and flow a 701, built a 601 and is currently scratch building a 750 so there is some experience around.
wing construction of the 601 required six 2x2x6foot thin walled steel tubing i have these here if the 750 construction requires tubing like this i would be willing to loan them out, tools too.
rbarnes3@maine.rr.com