RV-8 Elevator Travel

TomVal · #1 04-15-2009, 05:08 AM

We are in the final stages of completing a long list of mods on the aircraft. Yesterday, for the first time, I noticed that while holding full back pressure, the elevator would come off its full aft stop as the ailerons were being moved full left and right. Is this normal?

Thanks,

Rico320 · #2 04-15-2009, 07:59 AM

Had a similar issue while rigging my 7A. Ailerons would droop fifteen degrees when full aft stick was applied. The culprit was a binding rod end bearing at the left aileron push-pull tube/ control stick assembly. Very simmilar set up on the 8.

dedgemon · #3 04-15-2009, 10:29 AM

Quote:

Originally Posted by Rico320

Had a similar issue while rigging my 7A. Ailerons would droop fifteen degrees when full aft stick was applied. The culprit was a binding rod end bearing at the left aileron push-pull tube/ control stick assembly. Very simmilar set up on the 8.

The 8's control linkage is quite different from the 7's. The eight does NOT mix any aileron input with pitch. The side by side airplanes DO, although its very minor.

When you have full aft stick in the 8 and then you move the stick left or right, the elevator pushrod will be pulled forward slightly by displacement of the elevator linkage to the right and left in the back seat area. I would guess that this is what you're seeing.

Kevin Horton · #4 04-15-2009, 03:38 PM

Quote:

Originally Posted by DAGO

We are in the final stages of completing a long list of mods on the aircraft. Yesterday, for the first time, I noticed that while holding full back pressure, the elevator would come off its full aft stop as the ailerons were being moved full left and right. Is this normal?

It sounds like something is causing the elevator control linkages to jam up, before you hit the elevator stop, if the stick is moved to the side. It is important that the control travel be limited by stops at the control surfaces, to prevent damaging loads from being applied to the control linkages, if the controls get blown against the stops. The elevator should hit the stop, no matter where the stick is positioned left/right. You should figure out what is stopping you from pulling the stick further aft when full aileron is applied, and fix it.

John Collier · #5 04-15-2009, 07:59 PM

check the holes in the floor ribs where the pushrods run out...I had to open mine up with a small scotchbrite wheel

TomVal · #6 04-15-2009, 08:15 PM

Thanks for everyone's input. I just closed everything up a couple of days ago...and my back is still reminding me. We plan to look all the linkages over tomorrow. Maybe we'll get lucky and just find a rod-end locked up.

Regards,

tinman · #7 04-16-2009, 01:20 PM

Tom,
Are you getting ready to fly her to her new home in Summerville?

TomVal · #8 04-16-2009, 05:00 PM

Quote:

Originally Posted by tinman

Tom,
Are you getting ready to fly her to her new home in Summerville?

Hi Don,

I sent you a PM earlier today. Plans have changed a little. I hope to have it down there in May. My schedule is getting cramped and we were planning to drive out there with wife and dogs on May 15th. I may have a friend fly the plane to St. Louis and then later, after getting settled in at Charleston, I'll go get it. Please tell Don King to feel free to keep using the hangar.

Regards,