Testing & Drilling, page-57

Zero Ross 57. .... the rig positions itself over the well with a dynamic positioning system, and the location is fed from three different systems in case of break down of one or even two other systems....

Under the rig are a number of thrusters that keep the rig in the right spot.... the Cajun had four from memory....the same thrusters are used to move the rig around the field and also around the world.

It will do 6 knots at a normal cruise.... and around 1 knot if it moves with the BOP sanding below as it moves from fan to CNE-1

As it has no anchors outhe it does not require any vessels for a rig move.... one minute you will see it on location and the next it will be on the move. ..

Cheers jpg