A personal water craft (PWC) is a recreational watercraft that the rider sits or stands on, rather than inside of, as in a boat. Models have an inboard engine driving a pump jet that has a screw-shaped impeller to create thrust for propulsion and steering. They are often referred by the brand names WaveRunner, Jet Ski, or Sea-Doo.

Most are designed for two or three people, though four-passenger models exist. Stand-up PWCs were first to see mass production and are popular for single riders. The invention of both major types of PWC is credited to Clayton Jacobson II of Arizona, originally a motocross enthusiast.

Many U.S. states require safety training for personal watercraft operators. Modern PWCs include a lanyard attached to a dead man's switch, to turn off the vessel if the operator falls off, provided the lanyard is attached to the operator.

Lake Havasu, Arizona, is used for PWC riders and racers alike; the site has hosted the IJSBA World Finals for PWC racing each October since 1982.

Surfers use PWCs to get to waves and get up to speed with them; this is known as tow-in surfing. PWCs can also be used for towing water skiers on flat water.

Control and Handling

PWCs present safety concerns in terms of their ability to steer. Since steering is achieved from aiming the nozzle of the pump jet, there is no rudder involved, which means the craft cannot be steered in an emergency breakdown situation. Steering is significantly reduced when the throttle is not being applied; this leads to dangerous situations because it is against one's instinct in an emergency to accelerate. However, turning is not effective without doing so.

After market products are available to help with this problem, including different types of rudder steering systems such as Cobra Jet Steering. In 2001 Sea-Doo added the OPAS (Off-Power Assisted Steering) system, which uses rudders installed on the rear sides of the PWC to assist in steering.

Hazards

Apart from the obvious hazards of collisions and mechanical breakdowns common to all vehicles, PWCs feature the unique hazard of orifice injuries. Such injuries are the logical result of the unusually close proximity of PWC riders to the output end of the pump jet, as well as the fact that personal watercraft are usually not enclosed.

A rider who falls (or is ejected) off the back can land directly in the path of the PWC's high-pressure jet of water. Unless a rider is appropriately dressed in garments made out of a strong fabrics, the jet will easily penetrate any orifice it reaches. The consequences include permanent disability or death. So get properly kitted out.