Flying Moths

[khiemtran]

See these strange looking boats at the St George Sailing Club? They're International Moths. As you can see, they've got tiny wings on the bottom of their super-thin keels (technically known as foils).



Out on the water, these things will move in just the lightest breeze. Note how thin the hull is under the trampoline-like wings. The thinner the hull, the lower the drag.



But when their speed picks up a little, the hull doesn't add any drag at all... If you ever needed proof that sailing is a form of applied magic, take a look at the photo below.



These things are absolutely amazing to watch. And all this on a day when we were struggling to find enough scraps of wind to keep our dinghy moving. (As it happened, the Moth sailors were just setting up as we were leaving and they gave us a push out into deeper water to try to catch the breeze.)

Comments

[asakiyume.livejournal.com]

Wow, they are like beautiful semi-aquatic aliens.

Have you ever sailed one?

[khiemtran.livejournal.com]

No, they're way beyond my standard. The dinghy I usually sail has a hull at least five times wider.

[asakiyume.livejournal.com]

Would you ever like to try? (I think of you as going to Hogwarts School of Wizardry--that's what this sailing business is like--and maybe when you pass your OWLS you can try a hydrosail?)

[khiemtran.livejournal.com]

Making boats levitate is definitely fifth form material - I'm only at the second grade at the moment. We're just learning how to "hike out", which is like another form of flying - you put your feet under the toe straps and lean out so far that only your shins are still in the boat. It feels like you're soaring over the water when the boat really gets going (when it doesn't feel like someone is throwing buckets of seawater at you, that is).

[heleninwales.livejournal.com]

Wow! Wind-powered hydrofoils! I wouldn't have thought it was possible! I bet they take some sailing. They look as though the slightest wrong move on the part of the sailor would have them over.

[khiemtran.livejournal.com]

Yes, it looks quite striking when you see them coming towards you. Maybe there's some hidden stability provided by the foils, but I thought you'd still have to be a expert to stay upright.

[nojay.livejournal.com]

Kipling described racing foils like these over a century ago, calling them "bat boats" in "With the Night Mail". Much complaining about "boats" that flew between the start and the finish lines...

[khiemtran.livejournal.com]

Cool! Thanks for that! Although it looks like the bat boats also had some form of lifting gas as well.