Full size Lysander help please

[Peter Smedley]

I have been asked by the firm Gateguards to help them on a small project. They have a full size mock up of a Lysander and what the flying surfaces to be driven by Rc.

Of course it is static and won't fly. But I am asking what size of servo should be needed? I was thinking of 1/4 scale ones. The flying surfaces will be fabric covered and during our phone call I raised the subject of mass balancing. This would be feasible to cut down on the servo strain. I'm not sure of the weight of the surfaces yet.

Any ideas for size of servos? I haven't yet looked on Servo Database, this is my next job.
Thanks

[Rob Buckley]

You'll probably find that model servos won't move anywhere near far enough to move the surfaces of a full sized Lysander, and by the time you've mechanically geared them up to give a decent range of movement they'll be nothing like strong enough.

How much movement do you need?

[Peter Smedley]

Cheers Rob,
I have yet to find out. I could do some googling to try and get info.

[stuart knowles 1611]

My guess is that something pneumatic might be more in keeping with the motive power required although could the rudder and elevator could just be a closed loop cable back to the stick with muscle providing the movement force?

[Peter Smedley]

Thanks,
Gave it some more thought last night and found 6v linear actuators....could be the answer.