On Tue, 06 Dec 2005 15:52:16 GMT, "Mike Rapoport"
wrote:

It is probably due to structure on your airplane being colder than the air.
The triangles are probably reinforcements or doublers under the skin.

I will have to ask my A&P. I am fairly certain that on a Cherokee,
the inner wing is much simpler than that... Ie ribs with the outer
wing skin riveted to them.