Thorp Air Command - T18.net

I accidently pushed the trim rod down where it comes from the baggage compartment to the empennage (my arm slipped off the tunnel while trying to reinstall the bag.compartment bulkhead). Checked the trim wheel and, thru a small access panel, can see rotation of the rod near the rudder. The problem is that the trim tab seems disconnected. I was not the builder and am not in the habit of removing the vertical fin and rudder, but don't see any other way to get to whatever trim assembly is back there. I have my father's box of plans. From previous posts, I believe that there is a drawing for this assembly. Any suggestions? The Navy taught me to fly, but not to build/repair airplanes.

If its any consolation the rudder comes off with 2 bolts and the vertical fin only has 5 bolts. Then remove the cover under the vertical fin. This cover is held in place by about 8 screws on my plane. You can see the trim mechanism in all its glory once the cover under vertical fin is off. It sounds like that may be the easiest thing to do if you think the trim mechanism is the culprit.

Don't shy away from removing the fin and rudder. There are lots of things in there that need to be inspected periodically. First, of course, is the horizontal trim system. This needs to be lubed every once in a while. Other items include the elevator control arm and attendant bearings. Finally, look at the fittings for the tail wheel spring attach points. This is a known weak area. My belief is that all pilots should have a working knowledge of aircraft maintenance. You never know, you might like it!

_________________
Bob Highley
N711SH
SN 835
KLAL

Agree. And while you are in there, cut the top panel to make it removable without pulling the vertical.
Cubes

Yep...as Cubes Sez make a removable panel on the top side (both sides) . I tired to up load a pic from my gallery but it wouldn't work ? It will allow you to inspect and grease/lube the tail area and inspect the tail wheel attach fittings . It will make you life Mucho Easier !

RB

Higher and Faster

Well, I got the rudder and fin removed. Lo and behold! Nothing is wrong! The trim works OK.

I assumed that I had messed up and a seasoned old mechanic that was at the Vet's Day event said that the tab wasn't moving when I turned the trim wheel. I believed him w/o getting a second opinion. I was in too much of a hurry to think that I broke something. Now, I have go buy some lube while this is open and I have to come up with a connector for my tail light wiring. I had put in the tail light and put a connector there, but had too small of a hole in my fin post to allow the disconnect to pass through. Not very smart at my end.

He may have been looking at the stab and not the tab ? Good News is you got the tail off and can have a good look at the business part . I would take the opportunity to lube up the push pull tube bushings !

RB

Higher and Faster