RE: Gauging interest, Hellcat group build
Aerowoof,
My prototype will start out with a .61FX which I think will provide plenty of power for my tastes and fits totally in the cowl upright. I think either of your power options would work just fine as well. The cowl flaps are not operational but it wouldn't be a huge task to make them so. There are only the four cowl flaps on the -5 Hellcat to have to worry about.