Foxx, Thanks, I hope it helps him.. I debated putting a sliding canopy that was linked with my gear so when the gear retracted the canopy closed etc. I still can do that but I probably won't have it slide via an air valve. I built an interior for the plane which looks pretty good, hopefully... but its more plumbing that I want to do behind the cockpit. My plane is a Yellow P-47 with a glass fuse and not a lot of access behind the servos. I think I'll end up opening the canopy by hand when no one is looking LOL!!... BobH.