You might be surprised... Most boards I've seen built are at least conformal coated. Descending from altitude can result in condensation everywhere. I also wrote a spec for a new F-16 mission computer last year. You have to be able to open it up on the flight line in the rain, which pretty much demands hermetic sealing of the line removable modules.
I just recieved a 6 channel flysky this morning the bilge keel is done. It was a ain to do and I think I should have done it long before installing the guns etc. (lesson learnt) here's the front end of the Hood with rotating side gun and front fixed. It's beginning to look so good I'm happy and proud! and the double sterns.
