The "F" word

[Dave Krall CFII SEL SES]

Something else to check. While installing the new .060 dia. trim control cable, I found that the cable terminal nut or bug nut or whatever it's called, can be secured with the set screws in a way that locks the cable to the arm. This will cause the cable to bend/flex and fatigue as the arm travels through its arc. This condition is easy to spot at the elevator end but can be overlooked at the trim lever down between the seats.  
Joe S.

I've measured my stainless wire and it comes out to .050 dia.
I'm thinking it may be thick enough because stainless steel seems harder to bend.
I don't think .060 wire would go into the housing either, it's so tight.
Haven't decided for sure what to do.

[jjacky]

Sorry for such a late post but what was the final resolution of this problem. So far we have:

1. Make sure your trim cable is 0.06 diameter
2. Switch to a Stainless piano hinge
3. Make sure the distance to the trim tab bell crank from the cable mount to the trim tab bell crank is about 3 inches
4. Make sure the cable "bug" nuts at both the trim tab end and control lever end do not bind the control cable.

What else?,,,Thanks jbird

[kenryan]

What, if any, of this is applicable to the SuperSTOL trim?

[danerazz]

If the trim cable breaks, would you not want the flapping tab to leave the aircraft as quickly as possible? I don't know that a stainless hinge is good in this application. I think I would rather lose the tab than the whole elevator due to tab flutter.