FLAPPING WING-TO-FUSELAGE GAP SEAL

For the third time in about as many years, the rubber channel that acts as a seal between the inboard wing faring and the fuselage on the right side came loose during flight and proceeded to thrash away at the side of my RV-8. It did not do any damage but sounded like someone with a hammer banging away at my airplane. Fortunately, I had a short flight to get back to my home field.

It?s the original piece of rubber channel (12 years in flight and more like 15 if you count time in the box) so my fix for now is to replace it with new channel.

What puzzles me is that each of the three times it has been on the right wing, topside. The left side channel (knock on wood) has never been a problem.

Anyone else have this issue? And does anyone have suggestions for a fix? The last time this happened was about a year ago and I put some 3M weather-strip glue between the channel and the wing fairing. The 3M stuff really does not want to stick to the rubber (plus its messy as **** and hard to apply only where you waant it to go). I noticed after this latest incident that it basically stuck to the metal of the fairing but not very well to the channel.

I?ve included a few photos. As you can see, it cleans up easily and no damage was done other than to my nerves. Very inconvenient though and I?d like to find a more permanent solution. Suggestions welcome.


Right side rubber channel came free during flight


Rubber channel marked up the side of the fuselage but no damage


Clean up was easy. Now to replace with new rubber.

Chris

Is there a different gap between the wing to fuselage fairings on the right and left sides of your airplane? A too-large gap might allow the channel to come loose.

Happened to me twice on two different -7 builds. Problem was the wing/fuse gap was too tight at 1/8 inch. Opening it to >3/16 did the trick. Too narrow a gap influences the rubber to pop out.

John Siebold

Try using a little GOOP Automotive Trim Adhesive to hold it to the gap seal.

I suspect that the fairing is losing its flexibility with age, so new rubber will probably make a difference. If you want an adhesive, I have always found that pliobond (as old as it is - I was introduced to it back in the early 70's, and it was an old product then) seems to work really well for rubber to metal binding. Smells like a skunk - but it works.

Right versus left? no idea! Besides....no politics.....

Paul

I'm still on the original seals at 5 years and 600 hrs. No issue for the first couple of years then each side started creeping out near the 30% to 50% MAC location. I would poke them back in on preflight. The right one got to be enough of a neusance that I took it off, cleaned and glued it to the fairing with gorilla snot (weatherstrip adhesive). I was too lazy and short of time that day to do the left one. For some unknown reason, the left one quit creeping out. Maybe I got it reseated well during a subsequent annual. Don't know.
Both have been good for the last 3 years.

Now that I have said this, I imagine both will come out on the next flight.....

RV7ator said:

Happened to me twice on two different -7 builds. Problem was the wing/fuse gap was too tight at 1/8 inch. Opening it to >3/16 did the trick. Too narrow a gap influences the rubber to pop out.

John Siebold

Click to expand...

Wow. All of us posting within 9 minutes of each other. Now you know how slowly I type.
Interesting point. I made sure my gaps were small (surely 1/8") during the build and I have had the issue but to a lesser extent than the OP.

Very old tech solution...

Duct tape on the inside of the fairing, just a piece every few inches or so between the rubber and metal to hold it in place and keep it from pulling out...

Worked better than any adhesives I've used on rubber/metal...

Yes, you really can use it for about anything....

Mine popped out at about 1000 hours/10 years. This tends to get one's attention! I slowed to 100 knots and went direct to closest airport. I think a passenger's toe pushed down the root fairing a little, just enough to pop the aft end out.

As a permanent solution, I put a small screw through the aft end of the rubber part, into the metal root fairing. I didn't want any ambiguity at all about whether it would stay or not. It could be a pop rivet as well, as the only reason to remove it from the root fairing would be when replacing it.

Thank you all. Some interesting ideas here that I will experiment with. Gotta love the Duct Tape suggestion. Red Green would be proud.

Chris

3M 1300 Adhesive

You might consider 3M Neoprene High Performance Rubber Adhesive 1300----
I've experimented with it and this product "holds" the stock Van's rubber channel very well....

Mike

RV7ator said:

Happened to me twice on two different -7 builds. Problem was the wing/fuse gap was too tight at 1/8 inch. Opening it to >3/16 did the trick. Too narrow a gap influences the rubber to pop out.

John Siebold

Click to expand...

agree, 3/16 on mine with some goop on the trailing end.

chrispratt said:

For the third time in about as many years, the rubber channel that acts as a seal between the inboard wing faring and the fuselage on the right side came loose during flight and proceeded to thrash away at the side of my RV-8. It did not do any damage but sounded like someone with a hammer banging away at my airplane. Fortunately, I had a short flight to get back to my home field.

It?s the original piece of rubber channel (12 years in flight and more like 15 if you count time in the box) so my fix for now is to replace it with new channel.

What puzzles me is that each of the three times it has been on the right wing, topside. The left side channel (knock on wood) has never been a problem.

Anyone else have this issue? And does anyone have suggestions for a fix? The last time this happened was about a year ago and I put some 3M weather-strip glue between the channel and the wing fairing. The 3M stuff really does not want to stick to the rubber (plus its messy as **** and hard to apply only where you waant it to go). I noticed after this latest incident that it basically stuck to the metal of the fairing but not very well to the channel.

I?ve included a few photos. As you can see, it cleans up easily and no damage was done other than to my nerves. Very inconvenient though and I?d like to find a more permanent solution. Suggestions welcome.

Clean up was easy. Now to replace with new rubber.

Chris

Click to expand...

Thanks for posting Chris. Stuff gets old but why just right side?
I climb in and out of left side, sometimes disturb rubber seal a bit. Mine too has come loose there but not on right side.

I have couple black marks on left side, could have come from loose seal.

Reason right is coming off. Prop wash. Air is twisting around the airframe. I would think there's pounding on the top of the right wing close to the fuselage from prop wash.

Leadnut said:

Reason right is coming off. Prop wash. Air is twisting around the airframe. I would think there's pounding on the top of the right wing close to the fuselage from prop wash.

Click to expand...

That was my thinking as well of a possible cause. Thanks.

I have some good options for tackling this now with the suggestions here.

Chris