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Elevator trailing edge crack

bstell

I'm New Here
Greetings,
I have a new to me early rv4 (1986) that developed a crack in the trailing edge of the elevator. I guess it's best long term is to reskin/build a new elevator but I was hoping I could get some advice on a between now and then fix.i have a lead on an unbuilt tail kit I'm probably going to pick up for long term fix.i was thinking about making a doubler over that section of the trailing edge with some epoxy and pop rivets? And advice welcome. Thanks!
 

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Dent?

A crack from a rivet hole is common. Not sure what you have there and appears to be a dent too? Im not sure I would fly that.

A better picture and one showing more of the elevator might help.
Cm
 
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Cracks in Control Surface Trailing Edge

21 Years of RV-ator pages 46 and 47 discuss a repair method for a crack in control surface trailing edge. PDF attachment is scan of those pages.
 

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If you were going to inject anything in there I would recommend using something inert like Proseal. I feel that a stiff rubber-like compound would be better than using epoxy as it has a little bit of flexibility, but its not going to be that critical.

Do not inject foam - I've seen some horror stories when that foam accumulates water and causes corrosion. And if you have to use RTV make sure its a neutral cure product and not one that has an acetic acid base.

A doubler that rolls over the trailing edge will work nicely and I'm sure you could bond that on rather than use rivets to give you a very aesthetically pleasing repair.
 
I agree with Mike on the doubler applied over the trailing edge as a repair. I would suggest the doubler be long enough to restore the rigidity of the trailing edge as it effectively acts as the elevator rear spar. Adjust your counterbalance weight as necessary to compensate.
 
Awesome thanks for all the great replies! I talked to vans today as well, seems like everyone is in pretty good agreement.
 
I would suggest you call ( send the better photo) and talk to Vans support. This crack direction indicates a flex crack and could reduce the torsional stiffness of the counterweight end.

This would reduce your effective Vne.

2 cents . . . .
 
Maybe it's my old eyes, or the poor photo: Is the crack actually in the trim tab? Going half way (front to back direction) thru the tab?
 
Is that the outboard corner?

I'm not sure if you have the diagonal stiffeners in your elevators, but there was/is an optional stiffener to make the elevator more rigid. i installed them in my RV-4 build. With your "condition as is", I would definitely seek a repair or skin replacement. I had a similar ding in my rudder that looked harmless (happened at a fly-in), but allowed it to flex and it caused a vibration in flight on the way home..I slowed waay down and fixed immediately. I have attached a picture of my elevators showing where the diagonal stiffener is on most RV-4's with a red line shown at the location. It greatly stiffens the outboard ends.
 

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Optional stiffeners?

I'm not sure if you have the diagonal stiffeners in your elevators, but there was/is an optional stiffener to make the elevator more rigid.



I have a set of RV-4 plans and have been around the "RV thing" since 1991. This is the first I have ever heard of "optional stiffeners." Where did you see that?
 
I have a crack very similar to this on the trailing edge of the left elevator on my RV-6.

The plane has been looked at by a DAR, several A&P/IAs, other mechanics and many pilots and no one ever saw it as a concern. It is drill stopped and hasn't progressed in the 13 years I've had the plane. I see it every preflight, but don't worry about it at all.
 
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Elevator stiffener option

I have a set of RV-4 plans and have been around the "RV thing" since 1991. This is the first I have ever heard of "optional stiffeners." Where did you see that?

Something WAY back in my memory I can see something that has to do with those stiffeners. I think it was an option during building. Not sure where I saw it. I looked up in the 21 years of the RVator and found nothing. So: not sure where I heard or saw it but it was out there somewhere and a long time ago. I do not have those additional stiffeners and the elevators (and spar, by the way) look great after 1120 hours. :confused: My build started in 1992.
 
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