Leading Edge Wing Worms

Randy · #1 02-01-2009, 10:04 AM

My RV7A is kept in a hangar that routinely stays about 10 degrees warmer in winter and cooler in the summer than outside temps, this due to three walls being below ground level.

While gone away from the plane for about 6 months, the leading edges of both wings developed a pattern of little white worm looking things, each about 3/8" long and fairly evenly spaced, and about the thickness of a thick hair.

I think it must be corrosion and I will probably just get some very fine scotch brite and remove them. I am curious if others have experienced this and what the cause might be.

The airplane is unpainted of course. The only place these appeared is at the leading edges of the wings.

I don't remember flying through a white worm cloud...

The plane is powered by a turbocharged Subaru engine so maybe it has something to do with excessive speeds?

Randy C

Danny7 · #2 02-01-2009, 10:09 AM

sounds like filiform corrosion. i don't know anything else about it.

sorry

Steve A · #3 02-01-2009, 11:35 AM

I had my wings stored in the wing caddy that puts the leading edges about eight inches from the garage floor. I leave my garage open and apparently the neighbors cat came in my garage and "sprayed" my wings with urine. I had a pattern that looked like acid had been sprayed on my wings. With the humidity, the outer surface was impacted significantly.

Like most builders, I was planning on flying before painting but with this problem, I felt I needed to protect the wings so I painted the plane before finishing it.

This little episode does not change my outlook on cats. I hate them before and I hate them now.

S S Anderson
Lafayette, La.
RV 7A

TOAD · #4 02-01-2009, 12:20 PM

Yes Randy I have had similar problems. I feel that it is probably not cats in your case, but rather the rare form of filiform worms a close relative of the snow snake. These creatures will sneak onto your wings when ever you ignore you plane for a prolonged period of time. They leave microscopic white dust like scratch trails in damp weather.

I spoke with you over the phone, saw your plane, and you have my thoughts. I think it is filiform corrosion. Thanks to the other post for the term. (Note to builders

I did also have some of the same corrosion when I left my fuselage sheets of aluminum near standing up on edge on concrete for two years. I wonder if the reason for corrosion appearing on the lead is that the aluminum was flexed at that point to shape for the leading edge. The bend could have changed the aluminum properties so that corrosion forms more easily at that bend... That or maybe there is a 6 foot tall cat that can pee that high.

AlexPeterson · #5 02-01-2009, 12:35 PM

Randy, I'm not able to tell what part of the country you hangar in. However, at our airport in MN, there is a tiny amount of salt in the sand that they sometimes use on the runway when jets whine about braking (don't know why they have to put it at the ends of the runways...). In any case, I can wipe the leading edge of my wing after a few operations in the winter and taste salt. Nice. I can only imagine all the locations that salt dust is blowing into...

gbumga · #6 02-01-2009, 01:37 PM

Hi, spreading salt on a runway should be a crime. I promise you if they did that at my airport I would hound them night and day until they stopped it just to shut me up. I've found that the squeeky wheel gets greased, it's a pain in the behind too be a pain in the behind but it works. I have never seen salt used on the roads in the NW and my friends from back east can't believe the condition of the old cars here. No tires falling out of a rotted out trunk in the NW. Gene

Harvey L. Sorensen · #7 02-01-2009, 01:40 PM

Talking about cats. I had a guy tell me not to bad mouth cats because he liked them.. They tasted just like chicken.

mannanj · #8 02-01-2009, 06:16 PM

Quote:

Originally Posted by Harvey L. Sorensen

Talking about cats. I had a guy tell me not to bad mouth cats because he liked them.. They tasted just like chicken.

That reminds me of a bumper sticker I saw a while back. "I Like Cats---Dead Ones."

AlexPeterson · #9 02-01-2009, 06:32 PM

Quote:

Originally Posted by gbumga

Hi, spreading salt on a runway should be a crime. I promise you if they did that at my airport I would hound them night and day until they stopped it just to shut me up. I've found that the squeeky wheel gets greased, it's a pain in the behind too be a pain in the behind but it works. I have never seen salt used on the roads in the NW and my friends from back east can't believe the condition of the old cars here. No tires falling out of a rotted out trunk in the NW. Gene

They put some salt in the sand to prevent it from just being one frozen chunk. Now, that being said, I am no fan of it either, but the alternative is jets sliding off the end of the runway, so I would not expect to get far being a "pita".

Regarding road salt, what was experienced in Seattle recently would happen for about 4 months in the MSP area if they didn't apply salt to the major metropolitan highways. Cars wouldn't have a chance to rust, as they would all be smashed up in junkyards instead!

PCHunt · #10 02-02-2009, 03:17 AM

"So many cats, ........ so few recipes!"