Chapter 1: Know Your Boat
Jet Drives

• Jet drives propel a vessel by forcing a jet of water out the back of the vessel. Directing this jet of water steers the vessel.
• Personal watercraft are the most common type of vessels that use a jet drive.
• Jet drives also may power larger vessels (jet boats) and are used commonly for vessels designed for shallow water conditions. Jet boats can have inboard or outboard jet drives.

Jet drives use an engine to power a strong water pump, which sucks up water and then forces the water out the back to thrust the vessel forward. Personal Watercraft A PWC is a small vessel that uses an inboard jet drive as its primary source of propulsion, and is designed to be operated by a person or persons sitting, standing, or kneeling on the vessel rather than inside the vessel. The U.S. Coast Guard includes personal watercraft in the group of inboard vessels less than 16 feet in length.

PWCs are subject to all of the same laws and requirements of any other vessel plus a few laws specific to PWCs. Chapter 4 has the legal requirements for your state.

Be Part of the Action! Learn more about operating a PWC with this interactive animation. (Most students will already have Flash installed. If not, follow this link to install the Flash Player.)

Personal Watercraft Viewed from Front Angle

Personal Watercraft Viewed from Side

• Stern: Rear of a vessel
• Bow: Front of a vessel
• Draft: Depth of water needed to float a vessel
• Intake: Opening in the hull that draws water toward the impeller
• Intake grate: Screening cover over the intake, which prevents large debris from entering
• Drive shaft: The long stem connection between the motor and the impeller
• Impeller: Device used to pump and force water under pressure through a steering nozzle at the rear of the vessel
• Steering nozzle: Device used for directing the stream of water to the left or right at the stern of the PWC, which steers the PWC

Test Your Knowledge! Find out if you've learned the various parts of a PWC with this interactive animation. (Most students will already have Flash installed. If not, follow this link to install the Flash Player.)