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| Commando... |
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| "Commando" is a remote controlled monohedron power boat styled after the 118 WallyPower (chine, bow and profile) and the classical Chris-craft (plan and the rounded transom). The assignment required us to designed a monohedron remote controlled power boat, to be made of balsa and maximum length of 600mm. The weight, beam or draft were unrestricted. We had to use a specific motor, as well as a specific battery, prop shaft and propeller. This meant that the best hull form and best construction would win on race day at the end of the assignment. I went for an untraditional hull design, with a rounded bottom. Together with twin raked rudders (custom made carbon fibre), this solved the problem of poor turning at speed. However, regardless of LCG, I could not resolve the purpoising due to the lack of "Vee" in the hull. Still, I came second on race day. Following is a development of "Commando", named so after her paintjob. |
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| Paper mock up of the original concept |
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| Constructing a male mould |
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| The mould didn't survive - not enough release wax applied... |
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| Instead of steering with rudders, I decided to try pivoting the whole motor assembly... |
| A "CV boot" type arrangement was used to prevent water from entering through the stern... |
| Although turning was amazing, the propeller would suck in too much air and the craft was slow. |
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| Using the same delta fibreglass hull, I decided to try out a fixed motor with rudders arrangement |
| The rudders were custom made from carbon fibre and epoxy resin. |
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| The only time I ever did a very dodgy set up... |
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| While it went, it went FAST but only turned one way... |
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| Then everything broke, and I had to be rescued aboard Chris Moors's "Barge" - another boat in the competition. |
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| Minor damage... |
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| "Commando" was initially designed in Cobalt ... |
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| These lines along with section printouts were later used for construction |
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| This is where Commando gets her name from... |
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| Balsa is then sealed with epoxy resin |
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| Basic component layout. Only one option - FULL POWER AHEAD! |
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| The matching balsa cover before clearcoat... |
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| The matching balsa cover after the clearcoat.... or not releasing from it. It weighed 72 grams anyway - almost 10% of the total mass of Commando. |
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| Commando on a mission... |
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| Checking static trim... |
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| Testing revealed that the LCG is too far back |
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| Twin runners provided EXCEPTIONAL manouverability at full speed, but perhaps caused a little more drag. Commando was raced in this arrangement at the final race. |
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| I also looked at using hydrofoils on Commando. Although it would make an interesting experiment, I ran out of time to try them out. |