"Peter Gottlieb" wrote in message
t...
I would think that the "softness" of an air system would limit its
usefulness. I had heard that there were problems with fluid
compressibility
and component expansion on prototype high-pressure hydraulics (over 5000
psi) and air is much worse than that.

Small fast actuators are not an issue in a system simulating the motion of a
cockpit where 2 hertz is the outer limit in the s-plane.

kook eradication