We developed a leak under the bathroom sink between the back of the cabinet and inner skin. A connection on the outside manifold/one way valve was cross threaded, road vibration probably loosened it and it started to leak.
I noticed water dripping outside behind the roadside rear axle.
It was the rear plastic thumbnail fitting you see in the photo. Was able to stop the leak by un-screwing, coating the threads with two part construction adheasive and re-connecting.
"Sticks & stones can break your bones...and hail will dent your Airstream"
So when is this..."old enough to know better" supposed to kick in?