Cruise 4 Stealth Trimaran first tests

Sneaking up on a pelican—not

I snuck way from the solar boat project under cover of darkness to check out Claude’s radical trimaran—kind of reminds me of a stealth bomber especially in its current grey livery. The weather around these parts has been pretty rainy and windy as you can see from the photos.

Even though its not ideal for getting a reliable speed vs power consumption readings, it good to be able to get a sense of the boat’s performance against the wind. The photos here are from two days earlier.

Claude at the wheel—cutting cleaning through the water

Claude is the owner of T0rqeedo Australia, and has a tendancy to try interesting things, as you might have seen in our recent trip from Pittwater to Sydney. (And just google Claude Desjardins and you probably find something about his journeys around the Pacific.  Years ago he sailed the Pacific from Canada in an 18ft trailer sailor designed by Bruce Roberts.)  But back to the chase….

Claude wanted to have a small boat that could be easily driven so that it might be a good match for electric power.  So he commissioned Tony Grainger to design such a boat, without expectation of how a boat should look. As you can see, all bets are off when Tony gets a challenge.

Drag inducing turbulence is visible around the motor shafts

Keep in mind that this is its first river trial and there’s been no opportunity to fine tune critical speed aspects such as the paint job…  er,  I mean, the motor positions, and depth of the hulls etc.

The motor positions are critical for speed and efficiency and this has not been optimised in any way and we expect both speed and efficiency can improve radically with better positioning.   There’ll be other changes as well, and I’ll keep you posted on her development as she gets updated.

In this trial she’s set up with eight Optima batteries and 2 Cruise 4’s. On the day I was on board, it was very similar conditions to what you see in the photos. Below are the results from the data I recorded that day.

Despite its looks, its quite stable, and handled the gusty conditions on the day with aplomb. It knifes through the water and cuts through the wake of other boats with ease.  The motors on the day were fitted with standard props and so they topped out at a maximum power of below 7000 watts—so there is still more power available.  The motors had reached full revs, and so it needs faster props to get the best speed for this hull.  As well, there’s a lot of wash around the motor shafts and better positioning will reduce the drag.

You can see the video on youtube

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