Electric, dual action variable speed. I use a high end Makita, but found out it's really more about pads, compound and technic. You need to keep the glaze/polish "wet" when buffing/cutting clear coat. Use a black, foam waffle pad for cutting-ke the speed slow until you get the hang of it. I don't put the pad flat on the paint - I angle it to keep the pad going one direction and for control. Expect to throw waffle pads away after a coupl of sessions.

One trick I use is to get the waffle pad just damp before charging it with polish. This keeps the surface cool so you don't burn the paint. It's more like using the waffle pad to apply the polish, then slowly buff it out with the pad, letting the polish do the work, no pressure at all.

A 4 inch polisher would be ideal for planes, but I haven't tried one. Mine is a big blue 7 inch one. I favor the 3M and Meguire products. There's a white 3M polish, that escapes me -but stay away from it. It stains, but otherwise works ok. Stains all kinds of stuff...