Bollard Thrust is more commonly associated with tugs and towing vessels, basically it is a measure of how “hard” your boat can pull. It does not imply that your vessel is actually making any headway, it just calculates the strain you could put on a tow rope.

Formula

• 62.72 x ((SHP at propeller x (Ideal Propeller dia / 12) exp 0.67)

With our example vessel with 42 SHP available at the propeller and and Ideal Propeller Diameter of 14 inches we get a Maximum Static or Bollard Thrust of 855 lbs.