I have made reference many times throughout the cruising and mooring tips pages to Bow Thrusters and have put this information at the beginning so those who may not know will understand when mentioned what they actually do.
A Bow Thruster is an additional aid to manoeuvring a boat. It provides a boost to make the bow/front go port/left or starboard/right without even moving the steering wheel and without throttling backward or forward. Please note that wind and the river current may cause the boat to drift. In strong currents the boat may drift/move rapidly.
When turning a boat using engine power and normal steering the stern/back will swing. This is not the case with a Bow Thruster. This is very helpful for mooring and leaving moorings especially if it is just a couple hiring a boat. The Bow Thruster is also very helpful turning the boat around and when reversing as a boat is far less responsive to steering when going astern.
Some Bow Thrusters are on timers. The boatyard engineer should inform you. If this is the case just before approaching or as you are leaving moorings ensure it is turned on.
Some of the latest boats now have a bow/front and a stern/rear thruster which makes manoeuvring the boat even simpler.
Please note that the bow thruster is an aid and not a replacement of the steering wheel. It is not designed for prolonged continuous use. Using a few second bursts at a time is normally sufficient.