Jim:

yes, there is constant tension on the throttle servo in the "shut off" direction. Shutting down the engine from the throttle is the same as with a "push-pull" - simply lower the throttle stick and/or use your normal "throttle cut" on a computer radio. In addition, since I am using this setup with gas engines I have a computer activated "kill switch" setup.

I don't see a problem with this system shutting off the engine. The only times you could not shut off the engine would be if the battery(s) died or the throttle servo or throtte stuck. In those cases, you couldn't shut down the engine no matter what type of control you were using. In addition, if your throttle control breakes (servo arm, line, connectors. etc) then the engine automatically shuts down due to the throttle return spring.

As I said, this setup works fine for me. I have seen it used by others and haven't heard of any problems.

Dan