Experiencing Prop Walk

Understanding and utilizing propeller walk (or “prop walk”) is an integral part of learning how to reverse a boat with a single inboard engine drive type, so we’ll go into an in-depth discussion of prop walk here. Even if your boat is outboard or stern drive, it is prudent to take note here because one day you will be asked to take the helm of an inboard.

Exercise PW1 – Experiencing Propwalk

With the boat facing downwind and idling at 1000 rpm, put the boat into reverse at 2000 rpm and try to hold a steady course in reverse.

What you learned

The stern of the boat wants to go to the port (in most boats that have a “right-hand screw”). If the boat goes to starboard, you have a left-hand screw.

The terms right-hand screw and left-hand screw are defined as such: When viewing from aft, if the propeller turns to the right at the top of the sweep then it is deemed a right-hand screw.  Named “right-hand” because of the natural clockwise rotation of your right-hand wrist when it rolls out. Conversely, left-hand screw is counterclockwise when viewed from aft.

Most boats are right-hand screw. So why then does the aft of the boat move to the port when reverse is applied? This phenomenon is called prop walk.

The movement of the stern of the boat to port can be frustrating, but you can learn to use it to your advantage. First, let’s understand why the stern goes to port for a right-hand screw.