With an estimated 1.55 million personal watercraft (PWC) in use, these vessels make up only 8.6% of the U.S. recreational fleet. Yet in 2005, PWC accidents accounted for 1,007 out of a total of 3,451 serious boating injuries (29.2%) and 44 of a total of 163 non-drowning fatalities (27.0%). Hazard level per hour of operation is even more striking: A 2007 study by the California Dept. of Boating and Waterways found that for every hour of operation, a PWC is 24 times more likely to be involved in a serious accident than a canoe or kayak.
While cultural and lifestyle issues associated with PWC ownership may be a factor, there is also considerable evidence that certain design characteristics may contribute to the relatively high accident and fatality count.
This paper explores two important elements of PWC control: off-throttle steering and emergency stopping.
Off-throttle steering refers to the absence of steering control when there is no thrust from the waterjet propulsor. A common accident scenario involves sudden release of the throttle control when a hazard appears or is first noticed, followed by an unsuccessful attempt to turn out of the way. Most PWCs also lack effective reversing buckets, in contrast to waterjet propulsion applications for conventional boats.
Although manufacturers have addressed these problems in various ways, considerable debate remains over the effectiveness of their efforts. The debate extends to the role of various testing and advisory organizations in setting standards which may or may not be adequate. We also suggest techniques that my be useful to the forensic naval architect in reconstructing PWC collisions.
