Patrick:

The wheel wells of the aircraft have openings up inside them that lead back into the fuselage. These are likely the source of the higher pressures that is forcing air into your aircraft. There are articles in the flyer and in the tips manual about fabricating thin aluminum sheets and sealing these off.

William

William is right.

I’m pretty sure these holes were usually taped over or covered up at the factory. What I suspect has happened is someone has had a need to work in that area and removed the covering and didn’t see any good reason to replace it. After all it was just some covering in an inconspicuous place that will only need to be removed next time work is done in that area, right?

One simple method is to use two or three strips of sticky backed aluminium tape to cover across the holes. It’s simple to put in place, no screws or rivets needed and easy to remove at a later date.

Regards,
Alan