Personal water craft
This article is about Personal Watercraft. For other uses of PWC, see PWC (disambiguation). |
Pump-jet PWCs such as this Yamaha Waverunner are extremely popular for their speed and maneuverability. |
A
personal water craft (
PWC), or sea scooter, 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 names
WaveRunner,
Jet Ski, or
Sea-Doo, which are brand names owned by
Yamaha,
Kawasaki, and
Bombardier, respectively.
Because of their relatively low cost and the freedom they afford to owners, PWC are widely used for recreation. However, many U.S. states require safety training for personal watercraft operators. Modern PWC 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.
Most are designed for two or three
people, though four-passenger models exist.
Stand-up PWCs were first to see mass production and are still popular for single riders. The invention of both major types of PWC is usually credited to
Clayton Jacobsen II of
Arizona, originally a motocross enthusiast.
Lake Havasu, Arizona, is a favorite for PWC riders and racers alike, and hosts the IJSBA World Finals for personal watercraft racing each October since 1982.
Some
surfers use PWCs to get to the waves and get up to speed with them; this is known as
tow-in surfing. They can also be used for towing
water skiiers on flat water.
Although most PWCs are purchased by individuals for recreational use, they are also used for more serious purposes. PWCs are small, fast, easily handled, fairly easy to use, affordable and their propulsion systems, which do not have external propellers, are safer for swimmers and wildlife. For these reasons, they are sometimes used in preference to small
motorboats.
Lifeguards in some areas use PWCs equipped with rescue platforms to rescue water users who get into difficulties and carry them back to shore. Rescuers have also used personal watercraft to pick up flood survivors.
PWCs have been used by biologists studying marine life.
PWCs are also used for law enforcement. Due to their high speed and excellent maneuverability, police and rangers use them to enforce laws on lakes and rivers.
A PWC has recently been used for coaching rowing on the River Tyne. When combined with a wash-reduction system, it is an excellent vehicle for assistant coaches, especially when the BOSE waterproof tannoy is also installed. The latest integrated GPS systems allow for accurate assessments of time and speed of the crews coached. See
Phantom.
Before 1990, personal watercraft emissions were unregulated in the
United States. Many were powered by
two-stroke cycle engines, which are smaller and lighter than
four-stroke cycle engines but much more polluting. Simple two-stroke engines are lubricated on a "total loss" method, mixing lubricating oil with their fuel; they are estimated to exhaust in excess of 25% of their fuel and oil unburned in addition to the products of incomplete and complete combustion.
The 1990 amendments to the
Clean Air Act allowed the U.S.
Environmental Protection Agency to begin regulating personal watercraft and other off-road
internal combustion engines. The agency began a dialogue with manufacturers in
1991, resulting in regulations that were enacted in
1996. These regulations, set to phase in between
1998 and
2006, are averaging standards, allowing manufacturers to offset more polluting engines in their range by selling other engines that exceed the standard. The
U.S. state of
California has adopted more stringent regulations than the federal standard.
|
Even the largest PWC, the Sea-Doo LRV, can be easily loaded onto a trailer and transported from one body of water to another. |
To meet these regulations, manufacturers have adopted a variety of improvements, including increased use of four-stroke engines, the use of direct injection for two-strokes and the use of
catalytic converters and other pollution-curbing measures that overall have reduced emissions by approximately 75% compared to pre-regulation models.
In some areas, only new personal watercraft that meet the current regulations are permitted; an example is
Lake Tahoe.
Environmental groups such as the
Surfrider Foundation and the
Bluewater Network claim that more rapid progress could be made and the large numbers of older watercraft in use continue to emit substantial pollution.
Against this, industry groups such as the
Personal Watercraft Industry Association point out that environmental groups continue to cite pollution levels of pre-regulation watercraft and ignore the improvements made to newer models; and furthermore, that personal watercraft are unfairly singled out when they are no more polluting than other powered boats.
*
Bombardier Recreational Products (Sea-Doo)
*
Kawasaki (Jet-Ski)
*
Polaris Industries (out of market now)
*
Arctic Cat (Tigershark) (out of market now)
*
Yamaha (Waverunner)
*
Honda (Aquatrax)
*
Jet ski*
Jet boat*
Pump jet* Yamaha
Superjet* Kawasaki
JS550* Kawasaki
JS400*
U.S. Environmental Protection Agency.
Gasoline Boats and Personal Watercraft. Retrieved on
May 4,
2005.
*
California Air Resources Board.
Recreational Marine Engine Activities. Retrieved on
May 4,
2005.
* Chad Nelsen (1988).
Jet Skis Suck.
Surfrider Foundation. Retrieved on
May 4,
2005.
* Surfrider Foundation. (1988).
Minimizing the Impacts of Personal Watercraft- Part II: Seeking a Solution. Retrieved on
May 4,
2005.
* Personal Watercraft Industry Association.
[1]. Retrieved on
9 August,
2005.
*
Bombardier Recreational Products.
About Sea-Doo. Retrieved on
9 August,
2005.
* MIT Inventor of the Week Archive:
Clayton Jacobsen II Retrived on
15 March,
2006.
*
Personal Watercraft Industry Association*
American Watercraft Association*
U.S. Coast Guard Boating Safety*
x-h2o forum*
PWC Today *
How Personal Watercraft Work*
Proper Care and Feeding of Your Personal Watercraft
