Chapter 17 - Vance Atkinson's springboard and electric pitch trim systems

Updated 12/25/2019

Vance's canard is unique and shows a universal joint that isn't on the plans Cozy IV.   Rather than a manual rod, an actuator with feedback will be installed.  I don't think I'll need the component that mounts on the wheel well if the actuator has enough force.  It seems its purpose was to reduce the travel distance of the T-handle and to bias the trim so pulling the handled would provide up trim rather than down.  Update - several of us with Cozy IV's have had to add more layers to make this type of spring a bit stiffer in order to have adequate pitch down force at cruise speed.  Vance flew my plane and said that it handled well.  The pitch force was not to stiff.

Vance later updated to an electric trim system, but a downside was if there was run away trim, needed to be disconnected to allow full elevator travel.   He accomplished this with a quick disconnect pin through the Heim joint.  We tried different springs to allow full travel if there was run away trim, but Vance did not care for the resulting stiffer/softer forces.

Here's a link to a photo of the plans to make a Davenport spring