RE: Gyro calibrated Katana for Hover
I'd say theroetically the Co-Pilot could work. But good luck initiallizing it perfectly level. And on a plane, the senser needs to see in all directions, so mounting location might be difficult.
I had an old Co-Pilot 2 channel on my FP heli awhile ago. It was a pain to initialize it each flight session with the heli prefectly level, not sure if the newer version is easier. And don't remember if it had a feature where I could turn it off from the transmitter, you'd definately need that.
Give it a try, and let us know how it does?