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Rotor home............contact............rotor theory............project history............project future............video

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5 second clip

1 9.6 Mb Hi quality

10 second clips

2 3.3 Mb Decent quality

3 1.7 Mb Lo quality

20 second clips

4 10.3 Mb Decent quality

5 3.3 Mb Lo quality

6 3.6 Mb Lo quality

40 second clip

7 6.0 Mb Lo quality

Notes

Clips 1, 2 and 4 were taken seconds apart on 05 Oct 2007 at Portland harbour. Winds were light (one brief pocket anemometer measurement gave 4.5 kt), captain is Mark Tingley. I had taught Mark to sail the boat just then - it typically takes about one minute to convert a newcomer onto type. Nothing to it.

In clip 1 the flags show where the wind is - well aft of the optimum point, but the boat proceeds nicely. The boat behaves in nearly every respect like a conventional sailcraft, but you might notice her minimal heel, due to better L/D ratio than a conventional sail providing the same force. This shows well in clip 2, in which the camera picks the boat up as she accelerates from the jetty. The wind is somewhat ahead of the port beam in this shot. In clip 4 Mark brings the boat in. The boat has a very shallow draught and is quite frisky, but neutral on the helm.

Clips 3, 5 , 6 and 7 were taken minutes apart off Seaford beach in Sussex on 16 July 2005. The rotor powering the boat is my previous attempt, which I damaged severely only minutes after these clips were shot. This rotor was consuming about 24 watts in these shots, in a wind about 5-8 kt.

Clip 3.
The dinghy is seen accelerating from near standstill. The wind is from roughly 120 degrees relative to the bows. I've designed the keel (a daggerboard in this case) to slide fore and aft so I can establish the best CLR. The boat needs slight weather helm once under way.

Clip 5.
The dinghy is closest to the camera in this clip. It starts with the wind about 320 degrees relative to the bows; note how the speed falls off as I bring the bows left, and then picks up again as I turn back off the wind.

Clip 6.
The boat is accelerating from standstill, with the wind approximately abeam. You can see the retarding effect of the bows lifting from the water and slapping the waves - see how the boat speeds up again once the pitching has stabilised in the last couple of seconds. The rotor is very light, and with just one on board, in the stern, the boat needs ballast forward.

Clip 7.
This longest clip has the dinghy passing in a broad sweep, starting with the wind perhaps 70 degrees off the port bow and moving further forward as the shallow curve progresses.
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