At the front of RV Investigator there is one retractable bow thruster, which is like a propeller on a stem. It can be deployed below the ship and rotated 360 degrees.

In conjunction with the main propellers and the rudder, the bow thruster can turn the ship on the spot. This is all part of what’s called the dynamic positioning system.

RV Investigator's bow thruster from the Draft General Arrangement

RV Investigator's retractable bow thruster