Enter the bollard pull force and the efficiency factor into the calculator to determine the towing force.

Towing Force Formula

The following equation is used to calculate the Towing Force.

TF = BF * EF

  • Where TF is the towing force (kN)
  • BF is the bollard pull force (kN)
  • EF is the efficiency factor
    • The efficiency factor is a ratio of the total bollard pull force that is transmitted into towing force. This factor is dependent on several factors including boat size, speed, and shape.

What is a Towing Force?


A towing force, more specifically, in this case, a boat towing force, is a measure of the total force that a tow boat pulls a small boat with as it moves.

How to Calculate Towing Force?

Example Problem:

The following example outlines the steps and information needed to calculate the Towing Force.

First, determine the bollard pull force. In this example, the bollard pull force is found to be 60 kN.

Next, determine the efficiency factor. In this case, the efficiency factor is measured to be .45.

Finally, calculate the Towing Force using the formula above:

TF = BF * EF

TF = 60 * .45

TF = 27 N