Rudder trim use

[Dave S]

Do you have a rudder trim device on your kitfox?

[ken nougaret]

Does that include a fixed/bendable tab or a wedge?

[Peteohms]

Kitfox III yes-fixed.

[Dave S]

Ken,

Any type of trim system:)

[t j]

No on my classic 4 with left hand prop. I need to hold a slight pressure on left pedal or it will slowly bank to the right hands off. I have never felt it was enough to warrant a rudder trim device.

[jabkwab]

Classic IV with 912, yes-fixed

[HighWing]

i have servo controlled Rudder Trim.

[Slyfox]

I have electric trim with flap in the elevator. love it:D

[jiott]

SS7, Yes fixed. It flies ball centered with feet on floor.

[Slyfox]

I have electric trim with flap in the elevator. love it:D

woops, thought it said elevator. me bad. I have the rudder trim. it's fixed. can fly feet off the pedals at full throttle, ball centered.

[Esser]

I added provisions for one. See attached pics. I haven't cut the holes through the fabric to access this attach point. I will probably do it before it is flying though.

http://i1042.photobucket.com/albums/b423/joshesser/Kitfox%20Build/6A878D5D-BF44-48C7-A58B-54138F169603_zpsexadecs2.jpg (http://s1042.photobucket.com/user/joshesser/media/Kitfox%20Build/6A878D5D-BF44-48C7-A58B-54138F169603_zpsexadecs2.jpg.html)

http://i1042.photobucket.com/albums/b423/joshesser/Kitfox%20Build/E2E232B6-291D-496E-9FC8-6189A096013A_zpsyx7vsa6b.jpg (http://s1042.photobucket.com/user/joshesser/media/Kitfox%20Build/E2E232B6-291D-496E-9FC8-6189A096013A_zpsyx7vsa6b.jpg.html)

[Slyfox]

interesting, looks like you have it to put one on the left side of the rudder. sorry to say, mine needed it on the right side of the rudder

[colospace]

I did something very similar to what Esser shows, but I did one on each side with just two nut plates per fitting. I will determine what is needed once I finally get flying.

[rosslr]

I followed Jim's simple design of a 6" aluminum tab attached with a double sided tape. Simple and fast, easy to adjust, light and cheap. Took about an hour to make and attach.

cheers

r

[Dave S]

Ross,

Your's really sounds easy-peasy:).......would you be willing to share some details? How far up the rudder is your tab? You mentioned 6" tab - what is the other dimension sticking out past the back of the rudder? Do you have the tab stuck on the port or starboard side?

Thanks, Appreciate your comments

[rosslr]

Sure Steve - I'll take a photo when shortly and post it with dimensions. Be a couple of hours. But I basically followed Jim Otts advice posted elsewhere on this forum that goes like this.....

"I used a piece of aluminum 6" long by 2" sticking out & 2" taped down with heavy duty doublestick automotive trim tape. No sign of coming loose after 2-1/2 years. About 25-30 degrees of bend. Just use thin enough aluminum (~0.020) so you can experiment and change the bend without removing it."

cheers

r

[rosslr]

Here you go Steve. Dimensions as per Jim in my last post. I measured the deflection angle at 18'. I set it at 25' first and the ball was out the other side! Easy to just do small adjustments until you get it just right.

cheers

ross

[Dave S]

Hey Ross,

Thanks for the details and the photo...makes it very clear.

[Dave S]

First off, I want to thank the list members for sharing what they had done for rudder trim. I spent a lot of time trying to decided which way would work best (and easiest)....your contributions helped a lot. Admittedly, a kitfox does not take a lot of rudder pressure to keep it in line and a person can fly it just fine without, but I have to admit to getting butt-itus on the right side from holding right rudder on a cruise flight.:o

I had not considered rudder trim at the time of construction so there was not much chance to put something together attached to the structure of the rudder directly. So it had to be something attached to the skin.

I'd like to thank Rosslr for sharing the photo and measurements as an outside stick on is pretty much what I could do considering the plane was complete before I thought about rudder trim.

Also looked at some non experimental aircraft and found some with a tube trailing edge had the tab attached to the right side of the rudder and curved to the left behind the rudder - experimented with the size and vertical placement Ross used except attached it to the right side. Also used the 3M high strength auto trim tape with 4 1/2" strips to make up a 2" attachment surface.

The first trial had a little too much of a bend in the tab resulting in a slight need for holding left rudder in cruise. Ended up with a bend as indicated in the attached photos.

Works so well that I can't believe I flew so many hours without getting this done earlier!:o Now cruises hands off an feet off.

[HighWing]

Dave,
Looks really nice, and effective by your report.

I guess I am the only one who has a servo adjusting the trim. It was more of an experiment due to some ideas from long ago. I guess the important thing it suggested is that for the most part, variable trim in not really necessary. My experiment was to determine if creating an airfoil shape on the rudder - flat on one side airfoil on the other - would create sufficient lift to act as trim. In short - Yes it Does.

[airlina]

No Lowell you ain't the only one , I started with a ground adjustable rudder trim tab when I first built my Series 5 , but found it insufficient for my needs, so I added a high torque model airplane servo into the rudder with a cockpit adjustable trim knob that has worked great for me. I did a write up with photos long ago , and they can be found with a search. Amazing how effective that little tab is in keeping that ball centered. Bruce N199CL

[HighWing]

Bruce,
I do Remember now. At the time, I thought of the savings vs. the typically used servos.

Knowing what I know now, I would have used a hex wrench activated adjustment screw through a tiny hole in the fabric skin - saving a couple hundred $$.