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Course Outline

Boat operators need to be aware of a special risk when towing a person, particularly on an inner tube or other device which is difficult to maneuver. Learn about the “pendulum effect” in this animation.

Animation Transcript

Transcript for The "Pendulum Effect"

When towing someone behind a boat, particularly on an inner tube where the towed person has little ability to control their course, keep well away (at least twice the length of the tow rope) from the shoreline, docks, hazards, and people in the water.

A boat towing a rider on an inner tube enters.

Avoid congested areas, beaches, docks, and swimming areas. Water-skiing takes a lot of room. Some areas may have designated traffic patterns.

The boat passes close to a dock and a designated swimming area, full of swimmers. This is indicated as “not allowed.”

Why? If the boat operator turns the boat, the towed person will be swung out from behind the boat’s wake (on the outside part of the turn). The towed person can swing really wide depending on the boat’s speed and turning radius. (This is called the “pendulum effect.”)

The boat makes a sharp turn near a dock and the inner tube rider is swung outward, to collide with the dock posts.

When this puts the towed person in the path of the shoreline or object/person in the water, serious injury or death results.

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