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Too much elevator down

storkeye

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I’ve just rigged my VS and HS and all is good except for the elevator. I have 26.2 degrees of elevator down which is more than the 25 degrees max.

I used my digital level and zero’d it while the elevators were clamped in neutral, then removed the clamps and at full down deflection it goes to 26.2 degrees.

The elevator horns hit both up and down stops correctly and nothing is interfering.

Up deflection is 26.4 degrees which is less than the 30 max so that’s fine.

It looks like I need to add 1/16 to the down stop but of course that’s not going to be easy at all.

Any suggestions on how to fix?
 
I’ve just rigged my VS and HS and all is good except for the elevator. I have 26.2 degrees of elevator down which is more than the 25 degrees max.
I used my digital level and zero’d it while the elevators were clamped in neutral, then removed the clamps and at full down deflection it goes to 26.2 degrees.
The elevator horns hit both up and down stops correctly and nothing is interfering.
Up deflection is 26.4 degrees which is less than the 30 max so that’s fine.
It looks like I need to add 1/16 to the down stop but of course that’s not going to be easy at all.
Any suggestions on how to fix?

What is the minimum "up" limit? It looks as if you could simply length the pushrod to move that 1.2° to the up travel.
 
Minimum up

Minimum up limit is 25. The push rod is rigged with the elevators in neutral so I don’t think I can extend them without affecting the bellcrank or elevator neutral positions.
 
Minimum up limit is 25. The push rod is rigged with the elevators in neutral so I don’t think I can extend them without affecting the bellcrank or elevator neutral positions.

Increasing the length of the "aft" elevator pushrod will not affect belcrank positions. The only thing affected would be the stick position, and 1.2° will not be noticeable.
 
Check the dimension on your elevator rod-end bearings. If they're not close to the spec called out in the drawing, you'll get some whacky numbers for your up/down limits.

I learned the hard way. :mad:
 
Refer to drawing 27A, top left corner. There is shim F-711E & angle F-712D that can be trimmed to control elevator Up & Down stops.

I have seen (& fixed) a couple planes where the F-711E wasn't even installed...
 
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If you're hitting the stops (F-712D and F-711E) then I would consider a couple of courses of action --

1. Does 1.2° of full elevator deflection really matter? You're NEVER going to get there in ANY flight regime other than taxiing...(Live with it.)

2. Consider remaking the F-712D and F-711E -OR- modify the contact points on the back edge of the F-711E with a section of rubber fuel hose RTV'd into place.
 
Thank you

Thanks everyone for your replies and guidance. With your help I've found the problem and it is the F-711E elevator stop. The elevator horns don't contact the stop at 25 degrees. The stop is 1/16 short.

It might be that this is a non issue so before de-riveting and making a new part or finding any other solution I have emailed Vans for their advice.
 
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