Well it's all new to me too, I'll be doing some more research with my local outlet tomorrow. But, at the moment I believe the idea is to use a 'headlock' gyro. These are intended to keep helicopters straight independently to the rudder action of the tail rotor, so it resists horizontal plane rotations not inputted by the pilot. I guess that inputs by the pilot overide the gyro's activity to permit steering. By using such a gyro on it's side the horizontal becomes vertical ( gyro simply senses it's orientation in space and reacts to changes) . The unit I looked at in the shop simply fitted between the receiver and the servo that reacts to the gyros intructions, it's up to you to arrange the servo's activity resulting from that. I guess that the gyro's position dictates the degree of servo movement, so we would have to suss just how much that needs to be on the control surfaces (wings etc). Start with a trialled neutral position, which dictates the gyro's orientation in the boat, and when the gyros sees a deviation from that we need to ensure the movement of the control surface, including it's size and efficiency is able to adress the deviation detected and bring it back to neutral. In practice though the thing should put in real small constant trims so that mass deviation does not occur, that's the point of them of course.
To be honest this is all loose stuff that needs consolidating, I'll know more tomorrow when I've spoken to the shop dude and I have one to play with. I'll let you know.
This is the sort of thing, this one can be adjusted for rate under way
http://www.ebay.co.uk/itm/NEW-RC-Hel...21013723935%26