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OVEREASYGUY
06-28-2005, 08:51 AM
I'm learning to fly my new Supercub - wow what a good time - I feel 10 years younger!
One of my biggest complaints is the manual trim. It would seam like it would be relatively easy to put a switch somewhere and rig up an electric motor to turn that elevator trim knob.
Is this possible?
Carb heat is annoying also - is it possible to rig up a carb heat knob on the panel in front of you - instead of on the side. Are there STC's for such modifications?
Thanks
Cliff in Maine. N82225

Fortysix12
06-28-2005, 08:58 AM
On the carb heat -don't use it unless it's needed.

Sounds like your using your trim too much. If you fly it like most you make very small adjustments and you live with it. If your experimental then I would put in a servicable unit from a Cherokee or something, maybe an STEC for a wreck. It can be done. There's a lot of discussion on the trim here at this site.

behindpropellers
06-28-2005, 08:58 AM
I'm learning to fly my new Supercub - wow what a good time - I feel 10 years younger!
One of my biggest complaints is the manual trim. It would seam like it would be relatively easy to put a switch somewhere and rig up an electric motor to turn that elevator trim knob.
Is this possible?
Carb heat is annoying also - is it possible to rig up a carb heat knob on the panel in front of you - instead of on the side. Are there STC's for such modifications?
Thanks
Cliff in Maine. N82225

Sure. It is possible. But why add another 20 pounds, another system to make it more complex????

Trim it and forget it, if you are too lazy to work the manual trim maybe you should be flying a mooney or somthing :o .


Tim

p.s. On a side note, find sombody to run your trim knob on the ground. Watch it to make sure the horizontal stab runs smoothly up and down. If not, that is probably most of your trim problem right there. It is very common for the tubes to get rusty and bind. This will tear apart the rear horizontal stab support as well as make your plane fly like a truck.

Yard Dart
06-28-2005, 10:27 AM
Trim only for cruise and landing do not chase it.

cubunltd
06-28-2005, 12:16 PM
Overeasyguy,
Check out pics of instrument panel layout at:

cubsunlimited.com

PS. The other guys are right about the trim!



John

kase
06-28-2005, 12:24 PM
Mechanic here in town put electric trim in a Husky a few years ago and got a STC for it. Had a pistol grip with a toggle switch to operate it. They did it because the guy flying the Husky only has one arm. His left one is missing so he had a hard time running the flaps, stick and throttle with just his right arm. Worked really good.

Mikey
06-29-2005, 01:06 AM
I found dispite lots of lub on the jackscrew, lubing up the trim pulley at the crank end made the huge difference in how easy the thing operates. Don't know about the 18's but my -12 just doesn't have that sweet spot for cruise trim like most Cessna tails. Just the nature of the beast, no biggie, but you would probably drive your self just as crazy with an electric system, and wear out a lot of trim switches. I'm still on my original '47 vintage crank handle.
Chris

Taledrger
06-29-2005, 07:50 AM
Cliff,

If your previous experience has been in a/c where you trim the elevator itself (most Cessna) instead of the horizontal stab (most Piper) you will have a tendency to chase the trim because it doesn't feel the same when your trimming the pressure off. A little practice and you will get it. Putting an electric button on will give you even more fits trying to find a sweet spot.

Bob D

Jon B.
06-29-2005, 08:55 AM
If you insist upon an electric motor, a couple local EAA guys used a Chevy pickup window-drive motor. The gearing and such worked well for them. They put it on a Producer-type craft, built out of TriPacer parts.

They're rebuilding it after major wind damage. This time, she has a 6-cylinder Continental IO-360 and constant-speed prop.

Jon B.

Aviator
06-29-2005, 11:50 AM
Not a good idea, unless it's a must (e.g., one arm). As pointed out above, it complicates a simple system and adds weight. If you must have one, then you'll want to make it fail-safe. Add 2 sets of either-or limit switches, a separate kill-switch to stop a runaway, and a manual override. Also, you'll still need the indicator.