Retracting Drive Unit

The retracting drive unit in the 35 MKII is a little different from others that have been built.  Where others have employed single or multiple constant-velocity joints to keep the angular velocity constant, we can use a simple universal or Cardan type joint.  This works because the tail shaft is in alignment with the stub shaft coming from the gear when the unit is deployed.  The universal joint also functions as the hinge point for the strut.