So I've taken on quite the project. I'm building an AW609 Tilt rotor as a platform to develop Tilt rotor specific control software. The In order to fit all of my equipment I made this thing pretty large. It runs 2 Cobra 4130/16 390kv motors with Master Airscrew 16x10 3-Blade props. Now if you're not already familiar with how Tilt Rotor aircraft work then take a minute to google the v-22 osprey or the version I'm building, the AW609. Note the nacelles and how they pivot. During takeoff the motors in my aircraft are directly above the pivot point providing downward thrust. They can(should) rotate 20 degrees aft, and 90 degrees forward of this upright position. Now here's my big question. How should I drive the nacelles? Imagine I have a standard servo as a direct drive inside the nacelle (they fit) on the pivot point. During transition we rotate these motors to 45 degrees. I now have a constant torque load on the servo. With these motors and props weighing about 1.2 lbs each, what sort of equipment will I need to pull this off. I know there are servos powerful enough to do it, but I'm uneasy with the amount of current draw that comes from a sustained load like this that is a major part of the overall function of the aircraft. There's no need for high speed transitions in servo angle either. What would be perfect is a servo built for low speed, somewhat high torque, and good efficient holding power. Looking at specs just isn't helping me make a decision so hopefully some input will help guide me along here. Thanks! I'll post pictures of what I have already.