That small and fast sports car of the waves that you have seen on every lake and beach in America is a jet ski. These personal watercraft have been providing thrills and spills to watersport lovers for nearly fifty years.
Jet skis do have reverse, as well as neutral and brakes. A ‘reverse gear’ is achieved by swiveling the jet of water that normally pushes the watercraft forward by 180 degrees to apply a braking force which will eventually move the jet ski backward.
A Jet Ski, one of the two major brands along with Sea-Doo, is a kind of boat called a personal watercraft, or PWC for short, and is one of the fastest and most maneuverable boats you can buy. This motorcycle of the waves offers riders high-speed thrills for those brave enough to get on board.
How does a jet ski work?
The science behind jet ski propulsion is different to that of a conventionally powered boat. Rather than a propellor or screw pulling the boat through the water, a jet ski is pushed according to Newton’s third law of motion.
Newton’s third law says that every action has an equal and opposite reaction that happens at the same time. A jet ski moves forwards, or in reverse, exactly the same way that a balloon full of air whizzes around the room when released – the equal and opposite reaction of the air released backward pushes the balloon forwards.
In the same way, a big scoop on the bottom front of the jet ski picks up large amounts of water and pushes it through a tube with a pump inside. This pump works a bit like a turbine and pushes the water out the back of the jet ski at very high speeds and that force pushes the jet ski forwards.
To change directing in a jet ski it is only necessary to change the direction of water flowing out the back of the craft. To turn, a nozzle moves from side to side, and to go in reverse, a shroud or bucket turns the water so it pushes forwards which has the effect of moving the PWC backward.
Why does a jet ski need reverse?
If the point of a jet ski is to have as much fun a possible turning and jumping in a forwards direction, it might not be immediately clear why a jet ski needs reverse at all. While it’s true that nobody needs to parallel park their jet ski, there are still times that reverse comes in useful.
Approaching a dock or trailer at the end of your ride is a maneuver that needs to be handled with care. Personal injury, damage to your craft, the dock, or trailer can occur if you don’t take your time.
Ultimately, going in reverse is simply an extension of the braking process. So once you have brought your jet ski to a controlled stop, it might be useful to back up a little bit so you can tie off at the dock, or line up better to slide onto the trailer.
How dangerous is a jet ski?
Every activity has some inherent risk but used correctly a jet ski should not be any more dangerous than any other kind of boat, despite the dynamic riding experience. That all said, misuse, user error, and poor awareness can lead to injury.
Situational awareness is necessary to avoid accidents while riding a jet ski. The rider must look out for swimmers in the water, objects floating at or just below the surface, hidden sand banks, and other water craft to avoid a serious accident.
Jet ski riders must never drink alcohol and ride a jet ski, however tempting this may be while on holiday. Riders must also obey navigational buoys and respect the rights of other water users.
Riders must not ride beyond their ability and must always remember that a jet ski cannot make a sharp turn unless its moving fast – a common cause of beginners ploughing seemingly helplessly into an accident.
Should you buy a jet ski?
Jet skis are a relatively affordable way to get your thrills on the water. Costing only $5,000 for a basic model, even the best on the market can be had for about $20,000. After the PWC itself, the only things you need are a life vest, a tow hitch and a trailer to get your boat to the water.
So if you like the idea of cresting the waves at breakneck speed buy a jet ski and don’t look back.