Cabin water leak

[Mike Smith]

I'm considering looking into a small leak in my cabin that happens after a heavy or long rain. I think it may be one of these 3 areas:

1) Air inlet openings.
2) Wing attachment area.
3) Comm antennaes on top of the cabin area.

I was wondering if anyone has had luck in chasing down leaks. Mine never has any leak down/behind the instrument panel or down the windows or door posts. It shows up as a small drip in the headliner right where the overhead speaker is. My comm antennaes are just above where the pilot/copilots heads are.

Any hints on common "trouble" spots that I should check first?

Thanks,

[mit]

look aroud the wind screen.

[n2582d]

Mike,
If hosing your plane with water doesn't reveal the source of the leak here's another idea. Several years ago I saw a salesman from UE Systems demonstrate their ultrasonic leak detector at an IA renewal seminar. http://www.uesystems.com/ It was quite impressive in how it could detect even the smallest source of a leak. To find sources of water leaks one puts a ultrasonic sound generator on the inside of the plane and then points the probe at suspected areas of leakage from the outside of the aircraft. UE's detector is quite a bit more expensive than others. A quick search of the internet came up with some in the $300 range: http://www.reliabilitydirect.com/ultras ... rindex.htm

It's pretty hard to justify buying equipment like this for a once in a blue moon use. It would be great to see the association buy equipment like this for us to rent. A hefty deposit would discourage guys from "borrowing" it forever.

[Mike Smith]

Gary,
That sounds like the ticket, but I'll probably do some visual looking first. I don't think it's the windscreen because I never see any water around it either after it's sat in a heavy rain or while flying in precipation. After the heavy rain at OSH last summer I took off the next day and for the first few minutes after takeoff I got a leak from the headliner at about the center point between the front seat occupants. But absolutely nothing around the dash or firewall (cabin side). I have a hangar so I've been putting off a serious search for the leak point since I don't have it sitting out in the rain except on the occasional cross country trip. I figure it might be a good project for the next month.

Thanks,

[GAHorn]

Keep in mind that the original speakers mounted via machine screws THROUGH the cabin roof!
Loosen the screws from above/outside and use some sealant to seal the screws. Tighten them down before the stuff cures.
Another location for water leaks is the wing roots. Remove the fairing, use duct tape, etc to tape across the gap between the root and the cabin, and reinstall the fairing.
The lower and upper window seams are usually fine places for leaks. Thats a tricky one. You don't want to rigidly seal the window because it's supposed to float so it won't crack (so don't use Pro-seal etc. except beneath the lower mounting strip during windshield change-out, and even then you can create a pocket of captured water a-la corrosion, etc.) I like one thing about Piper....they make a zinc-rich mustard-colored putty that is non-corrosive and seals up water leaks.