Dart River Jet Boat

The jet boat ride up the Dart River was fun, although I have some bruised ribs which are still a little tender.

We did six 360 degree spins. It was on the second that I was pressed into the metal bar at the side of my seat abruptly and forcefully, which was absorbed by a couple of ribs. Ouch! I was sitting too relaxed, instead of bracing hard to resist the motion.

I learned a few things about the jet boat:

It was invented by a New Zealander, who put an irrigation water pump into a plywood boat hull, driven with a car engine.

It can travel at high speed in as little as three inches of water.

Steering and stopping is performed by aiming the jet nozzle.

The most interesting thing, to me: In order to travel in shallow water, the hull has to be made to hydroplane on top of the water (instead of floating in it). On my jet boat ride, the pilot was having difficulty, initially, getting the boat to hydroplane. Eventually, we had to return to dock and rearrange the people in the boat, putting the lightest people at the back.

The problem is that, while the boat is floating and trying to reach “critical speed” to hydroplane, the pump intake is sucking the back of the boat downwards, which fights against the lift needed to hydroplane. Even then, after stopping, we had to stand up and lean forward to help the boat rise up.

Once the boat is hydroplaning, it is very fast and very maneuverable! It also burns one litre of fuel per minute, in its eight litre V8 engine.

The Dart boats are also not the fastest. The Shotover Jetboats are twin-engined, and go even faster! They also do more of a “thrill ride”, but I think I have had enough jet boat thrills. I don’t need to pay another $200 for a slightly more thrilling experience.