On 30/09/2010 21:11, Andy Champ wrote:
On 30/09/2010 20:58, Clive George wrote:
On 30/09/2010 19:23, Rick Cavallaro wrote:
You know dennis - you look a bit silly simply ranting that we're
liars, fools, and hoaxters without even attempting to tell us
specifically how you believe we violate any law of physics. If there
is a problem with the analysis JB posted point it out. It's about the
simplest derivation you could hope for.

Ignoring Dennis, who delights in proving how wrong he can be on a
regular basis, I have to say I found the explanation of how it works a
bit opaque. I'm pretty sure I've got it, but the text and diagrams
didn't really help that.

It does require a bit of a twist in the way of thinking about it - that
the wheels drive the windmill, not the other way around as you'd expect!


And metric just makes things easier :-)

Hey, they're Americans. They like to make things hard for themselves by
mixing units. Just ask NASA...

Rick, JB, if you want another challenge... there's a bunch of guys over
on uk.rec.sailing who don't believe you either. Which bearing in mind
that most of them have seen fast boats tacking downwind at more than
windspeed is impressive. It's come up before, but never with first hand
experience - and that's why I didn't need persuading. The streamers on
the video I saw persuaded me it was no fake - the effects were too good
for Hollywood!

Trouble is it needs the connection to the ground that a boat doesn't
have, so having a sailing background will naturally confuse things.