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Anyone have autopilot in their cub?

No dice on the full travel. it’s too bad would have been a great location, concealed and easy to access inspect/adjust. Im going to try making a longer arm but im not optimistic, it’s a long swing to cover the elevator travel. maybe someone else smarter than me has a hack to make the arm work vs the pulley?
You should be using the capstan style of servo for full travel. Mount it aft of the baggage area.
capstan.jpg
 
Only applies if optional auto trim is installed. I don't know how common that option is but it's not used by CubCrafters.

With the basic pitch and roll servos the Garmin system gives a "trim up" or "trim down" alert when the pitch servo is holding torque against an out of trim condition. The proper response is often a change of thrust rather than a change of trim.
Yea, Have a few friends with the Garmin stuff in a 182 and a Bonanza. I bet there are some Garmin software engineers working overtime. Engaging the autopilot at 2-300 feet in a Bonanza and getting a runaway trim could be disastrous.
 
Steve, they have a software fix which is why it’s released for experimental, but they are waiting on paperwork approval for the certified.


Sent from my iPhone using SuperCub.Org
 
Trim tabs are pretty simple to overpower for the duration a guy would need to hit the disconnect button. I don’t know of anyone running a jackscrew trim with their autopilot. I’d suggest a Safety Trim controller for anyone with electric trim on a trimming horizontal.
 
I don’t know of anyone running a jackscrew trim with their autopilot.

I have seen reports that some CubCrafers owners have tried it but no reports that anyone who tried it decided to keep it.

Many, if not all, Part 25 aircraft drive the stabilizer jackscrew to compensate for the AP holding elevator against a pitch mistrim. These aircraft typically have fully integrated autopilot and autothrottle.
 
Trim tabs are pretty simple to overpower for the duration a guy would need to hit the disconnect button. I don’t know of anyone running a jackscrew trim with their autopilot. I’d suggest a Safety Trim controller for anyone with electric trim on a trimming horizontal.
Main issue I could see would be with the Bonanza where the trim can over power the elevator. I know a guy who did not set the trim on a Bonanza correctly for take off and dam near killed him. My wife and I forgot to set the trim on our 182A once for take off while doing touch and goes, it was very heavy it pitch till I got it trimmed. That was my concern. On a Cub I don't think it would be hard to over power and turn off if the stab trim was rigged up.
 
By extending my arm .20 I was able to achieve full range of motion at this location and the pushrod is protected by the under seat storage and its clear of all cables and pulleys.
IMG_7398.jpg
 

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How acute is the angle of the rod? I wonder how that plays into servo power?

I see you buried the servo below the baggage floor after looking at the other pic, so pretty level rod, I presume. I like that location. Nice work!
 
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Dedicated controller or G3X only for autopilot?

I am making this decision now - whether to include a dedicated controller or just utilize G3X’s onboard functions for our planned 2-axis autopilot (no trim - just altitude hold. We are set to install a trim servo if it’s needed, but the MOAC’s don’t seem to have the same need for trim as the Rev 2 & 3 Backcountry Cubs).

Any updated recommendations for a Cub that will live in AK and frequently goes on long VFR cross countries within the state?

For comparison, I find myself using the Skywagon’s 2-axis STEC30 autopilot much of the time when traveling VFR from area to area. This usage is typically just heading and altitude hold. Very little IFR flying or approaches.

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Here’s how Legend Cubs typically sets up a G3X panel with 507 controller to right of primary display. I won’t be putting in an IFR navigator or G5 unit. Pic below that is demo of G3X flight director page displayed along with with primary page.

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I sorta wish I had the 305 or 507 controller. The AP would be more functional. No plans to upgrade mine. It does enough as it is.
 

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FWIW I'm doing the same without the 'full' dedicated controller. The Dynon does have a simplified controller with a physical heading and altitude knob and I have that. For the rest of the stuff I will just use on screen - but not for IFR so mostly use the simple knob panel 90% of time.
 
Another vote for the 507 controller if you’re using a GFC500. While the G3X interface works, if you use it much my opinion is a stand alone controller is really helpful. I like knobs and I’ve spent quite a bit of time “dialing-direction” through heavy traffic areas.


Sent from my iPhone using SuperCub.Org
 
Another vote for the 507 controller if you’re using a GFC500. While the G3X interface works, if you use it much my opinion is a stand alone controller is really helpful. I like knobs and I’ve spent quite a bit of time “dialing-direction” through heavy traffic areas.

I have the GMC 305 but only because a GMC 307/507 won't fit in my panel. Having dedicated mode select buttons is more convenient than using the AFCS GUI but I don't really miss the GMC knobs. I find it very easy to set altitude and heading bugs with the left knob pair on the GDU.

Certified (IFR) systems require the GMC 507 since it includes a redundant AHRS that is not provided in any other GMC version. That's not a factor for experimental as attitude redundancy can be provided with a second GSU 25 or a G5.
 
Modern RC servos can be bought or ganged together that will fly a 1/2 scale model. Trimming a full scale in no biggie. Don't worry about the servos, it's the cavalier approach to the pushrods, some are scary, I'd be using arrow shafts.
 
I know this is an old thread but maybe someone can help. Javron Super Cub wide body. Got the autopilot brackets from Jaye. Been scratching my head figuring out how these go. Anybody got any ideas? Thanks
 
I know this is an old thread but maybe someone can help. Javron Super Cub wide body. Got the autopilot brackets from Jaye. Been scratching my head figuring out how these go. Anybody got any ideas? Thanks
The first two pics I took at Jay's shop. This first one shows the under-seat aileron mount (that is Jay's airplane that is shop) - I could not make this work with my large Dynon servo. But you can kind of see how the parts would go.

IMG_6372.jpg


This next one is what goes under the rear baggage. All I got was the big tray (black in this pic) and I will have to custom-make the part to hold the actual servo up - again my Dynon servo is way longer but should not be an issue for the elevator one. That tray then goes on those tabs they probably already welded on the fuselage - I have not installed the elevator one yet so not much more help.
IMG_6508.jpg

Then below is what I had to do under my seat for the Dynon servo - made a custom bracket out of steel that spans the seat frame and then there is a third attach point welded to the seat tube (bottom of second pic below can see it better).
IMG_5403.jpg

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EDIT: I have the same - widebody Javron.
 
The first two pics I took at Jay's shop. This first one shows the under-seat aileron mount (that is Jay's airplane that is shop) - I could not make this work with my large Dynon servo. But you can kind of see how the parts would go.

View attachment 105662

This next one is what goes under the rear baggage. All I got was the big tray (black in this pic) and I will have to custom-make the part to hold the actual servo up - again my Dynon servo is way longer but should not be an issue for the elevator one. That tray then goes on those tabs they probably already welded on the fuselage - I have not installed the elevator one yet so not much more help.
View attachment 105664
Then below is what I had to do under my seat for the Dynon servo - made a custom bracket out of steel that spans the seat frame and then there is a third attach point welded to the seat tube (bottom of second pic below can see it better).
View attachment 105665
View attachment 105666
View attachment 105667
EDIT: I have the same - widebody Javron.
Thanks so much for the reply. This helps alot.
 
The G3x can drive the autopilot without a control head. Just touch the FMA (flight management annunciator) bar above the primary flight display and the auto pilot control window opens in split screen.
 
I spent the first 18 months with my CC EX-3 without an autopilot, trying to be a purist.

Then I added the two servos under the seat. With CC brackets and all it cost about $2500. Experimentals are a bargain.

Still trying to be a bit of a cub purist I suppose, I did not add the control panel. Trying to keep the panel simple (yes, there is the G3X). I find it easy to control the A/P through the G3X for my VFR flying. To change modes you do have to touch once to bring up the autopilot control screen, but in heading mode you can just change the bug with a knob. If you drop your phone you can just engage the a/p with the button on the stick and it will hold pitch and bank while you retrieve it. When it is following a Direct To on the GPS, it will do VNAV down to pattern altitude just like the big boys.
cub panel.jpeg
 
As Steve mentioned it does work using the G3X as an interface, but the GMC507 mode controller really really makes it user friendly. I’d like a physically smaller version but I would always recommend it.
 
This is the set up I flew back from Lewiston, ID. I got pretty proficient at using it. Flown in a Bonanza a few times with the same setup with some guys that know the system very well. Pretty impressed with it's capability.
PXL_20240319_200955628.jpg
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All you need to ad is a reclining seat and a seat shaker to let you know when you get there

Glenn
I use to feel that way but after flying my Super Cub two hard days to get to Idaho it is kinda nice to travel in an airplane that is comfortable, capable of playing and I am not worn out when I get there. Too bad I can't afford one. I guess this is why so many of our friends have bought Cessna 180s.
 
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