Question

The primary function of the thruster in the Dynamic Positioning System of an offshore installation is

• A. To apply thrust in the direction opposite to the resultant environmental force
• B. To apply thrust in the same direction as the resultant environmental force
• C. To apply thrust in the direction opposite to the motion
• D. To apply thrust in the same direction as the motion

Hint:

In a Dynamic Positioning System, thrusters counteract environmental forces by applying thrust opposite to the direction of these forces, keeping the vessel in position.

Answer 1

The Correct Option is A

The Dynamic Positioning System is used in offshore installations, such as drilling rigs and vessels, to maintain position without the need for anchoring. The DPS utilizes thrusters that adjust the vessel's position by counteracting environmental forces such as wind, waves, and currents. 

1. 1.The primary function of the thruster is to counterbalance the forces that would otherwise cause the vessel to drift. To do this, the thruster must apply thrust opposite to the direction of the resultant environmental force (i.e., the combined effect of wind, waves, and current). 
2. By applying thrust opposite to these forces, the vessel maintains its position. This is critical in offshore operations such as drilling or dynamic surveys where precise station-keeping is required. 
3. Option B, to apply thrust in the same direction as the resultant environmental force, is incorrect because it would accelerate the vessel's drift, defeating the purpose of the DPS. Similarly, options C and D do not represent the role of thrusters in maintaining position relative to external forces.