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Fortysix12
03-12-2011, 08:51 PM
1641164216401639Probably the most sought after photos there are, for me anyway.
http://www.supercub.org/forum/images/misc/pencil.png

FdxLou
03-12-2011, 09:11 PM
Jeff

Have you flown it with the Dynon yet?

Lou

Fortysix12
03-13-2011, 02:21 AM
Today. I still need to install 5.4 software updates that are supposed to be the ticket for cub flight. Flight report tonight I hope.

FdxLou
03-14-2011, 09:37 AM
Today. I still need to install 5.4 software updates that are supposed to be the ticket for cub flight. Flight report tonight I hope.

Any news Jeff?

ohansen
03-14-2011, 11:50 AM
Thanks 4612 for the pictures!!
Wish I had those a year ago. Would have saved some of the remaining hair on the top of my head. I struck out on my own and used the capstan servos for both elev. and aileron control and placed the aileron unit in the wing where it could connect to the cables with enough room to give full throw. Hope to find out if it works out, later this year. If not, I'll try out your approach. My elev. solution is almost identical to yours. My wife tell me that at least it keeps me out of her hair now that I'm retired.
Are you using the SV system to run them?
Looking forward to hearing the flight report!
Ole

Fortysix12
03-14-2011, 03:03 PM
The preliminary report is good. Flew a 2 hour leg from Clearwater to Pompano using the GPS track only with altitude hold. It held altitude and coarse suprisingly well. Small osilation on the NAV GPS track, about 1 degree plus or minus. I will have to say I'm impressed. This wasn't before Kirk at Dynon helped me through changing some of the servo parameters. I will post the roll and pitch servo configurations later. I did change the bank rate to 0 which had very positive results on managing the adverse yaw. Flight conditions were smooth ,7500ft. I should note that even though it hunted slightly maintaining the coarse ,it was barely noticable. The bearing to destination never deviated from 141 degrees onces established. I have had to turn up the torque value to 100 percent on the roll and I'm running 75% on the pitch. The slipping is not a bad thing and I'm studying the behavior of the airplane while in full auto control mode. I have not installed the software upgrade yet. It is also important to configure the GPS, a 396 in my case for the right information rate, I think its' aviation in and NEMA out,which configures for a 9600 baud rate. I Know that I need to correct the flight control tension which has reduced since the C of A. I have around 250 hours on her since last May. I plan to take out as much of the stick slop to minimize any external plane induced problems - the servo can sense slop. I will continue to give flight reports and calibration information as it is generated. Also used the altitude preselect. Using the information for vertical navigation from the Garmin , I preselected a 1500 ft altitude. When initially setting up the D10A I set the rate of desent to 500 fpm. I'm not sure this will work in the long run because in my particular case, with out making a power change I am quickly into the yellow arc and I can no longer trim the airplane because of wind loads across the stab.It did level off at 1500 ft. then 1000 as I selected. The HSI page is working perfectly and now that the GPS is configured correctly I have the full NAV information on the HSI that includes the verticle navigation during decent. Electric trim might be in order to be able to maintain a higher speed at 500 fpm,keep in mind this are the results from one flight. I will also say that the rudder trim is working as planned. Wouldn't be with out it. It's interesting how much the skidding changes with weight changes. The heavier the the load the less rudder trim required. I'm trueing at 114 mph. So far so good. I
'm looking forward to testing the 180 option. I may change the maximum bank angle to 15 degrees. Jeff out.

Ole,what is SV system? I have a Dynon D10A with remote compass, OAT, capstan and rod arm servos. I'm currently using 5.3 version of software. Home built Super Cub.

ohansen
03-14-2011, 06:32 PM
Excellent report Jeff, thanks!!
The SV I was refering to is the Dynon "Skyview" system. I've committed to that now with the purchase and install of the ADAHRS box.
Not sure how it is all going to work out since their low tolerance for magnetic field bias and other install parameters for it are pretty near impossible to achieve in a cub. As far as I can figure, anyway. I've placed The ADAHRS slightly behind the extended baggage rear bulkhead in as nearly a neutral location as I could find. It's all very interesting though, and truly "experimental". As I mentioned, I opted for the capstan servo for the aileron control, simply because I could see a way to install and connect to the cables in the wing but could not, using the torque tube. It should work out but wish we could have conferred. Should not have been so bashful about posting questions I guess.
I had just finished covering the Smith Cub when we escaped to the south for the winter and am hoping to finish it this next 6 or 8 months.
Again, thanks for the report Jeff, and keep them coming. There are probably others, but I only know of you and FdxLou who have done this, so there is not a lot of info available on "auto piloting" a supercub (experimental, of course)
Ole

FdxLou
03-14-2011, 09:27 PM
Jeff

Good to hear the first flight went well.

My early efforts with my TruTrak A/P were also good as long as there wasn't much turb. Once it got beyond light chop the airplane would begin to dutch roll. It would progressively get worse until I had to disconnect the A/P. Eventually they designed an A/P (ADI Pilot II Gyro) with 2 gyro roll modes to act as a poor man's "yaw damper". All I know is it works in whatever chop I encounter. Jim Younkin said that a Cub with squared tips and extended ailerons was the most difficult airplane he had ever tried to "tame" with an A/P!

Hopefully the program written for your A/P by Dynon will handle turb. Looking forward to hearing more.

Lou

ohansen
03-15-2011, 10:23 AM
Thanks for the helpful info Lou,
Auto piloting a cub is a lonely endeavor. My reasons for attempting it are similar to the ones you posted some time ago, and for the challenge. The Dynon system requires large doses of inventiveness to implement, but smaller doses of $'s.. Hopefully, they will be there with software solutions for us too .

Fortysix12
03-16-2011, 05:30 AM
Return flight went also well. Lou, I need a base line for reference on what is and is not acceptable. I'd like to fly your autopilot. I have had to turn up the torque on the Roll servo to 100% and I'm up to 90% on the Pitch. Higher sensitity values seem to fly the plane better in light to moderate turbulance. I can tell it's going to take more than just a few hours of flight to fine tune the instrument. Cable tensions are the next item in line to see if this improves reducing the hunting. I continue to get the yellow flags in moderate turbulance which indicate servo slip so 52's might be in order. Lou, what strength servos are you using with the TruTrac? Do they rate them like Dynons?

Fortysix12
12-02-2011, 05:24 AM
Update. I continue to work with Dynon trying to perfect it's operation. I have replaced both servos with 52's in order to stop all servo slipping. It has cured the problem. One persistant problem that has not been able to be resolved is the wandering left and right of coarse by upto 3 degrees while in the Heading mode(roll servo). Tracks perfectly on Nav and TRK mode. Altitude is stable in smooth air not has stable in light to moderate turbulance. Dynon has added addition parameters to allow fine tuninng of the Pitch servo but still serching for the write combination of values. My system does have the remote magnatometer with regards to the heading operation. The Remote compass indicator is very accurate and stable. So not sure why the autopilot won't fly a stable heading in the heading mode.

ohansen
12-02-2011, 08:31 AM
Thanks 4612
great update & glad to hear it is working out well so far.
I am in the process of installing the skyview system, but beginning to doubt my decision due to the mag. compass being integrated with their ADAHRS (was seduced by the synthetic vision & map). To stay within their location parameters requires a fuselage installation due to fuel tanks & hardware and of course impossible to find a mag. neutral spot. They have mentioned on their forum that they may tweak their software (in the future...sometime) to allow it to be mounted further outboard in a wing.
It seems like a great product from a great company. Glad someone else is experimenting too.
Ole

skywagon8a
12-02-2011, 08:44 AM
46-12,
Don't know if this will help but, I have a certified Century II in my 185. I found the same wandering when in NAV mode. To solve this I now always use the LOC mode for heading stability. This increases the heading sensitivity of the auto-pilot. It seems that it is not totally the auto-pilot but it is the actual VOR nav signal that is wandering around in the either and the auto-pilot chases it. When I switched to a GPS nav source it still wandered a little in NAV but is rock solid in LOC.

I also found that it is more stable when the plane is loaded further aft in the CG range while on auto-pilot.

Roger Peterson
02-04-2012, 09:16 PM
Jeff, what length arm are you using on the 52 on the torque tube.
Looks like a great installation.
I was going to try both capstan units and start with the smaller ones, but I like your approach better.
Are you using the Skyview.

Roger Peterson
02-05-2012, 02:53 AM
I was so busy looking at the servo mounts, I totally missed the discussion about what system you were running. Sorry..