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From: Y.Porat on 1 Aug 2010 07:59
On Jul 30, 12:11 pm, "Cwatters"
<colin.wattersNOS...(a)TurnersOakNOSPAM.plus.com> wrote:
> "John Doe" <j...(a)usenetlove.invalid> wrote in message
>
> news:4c529e1b$0$21228$c3e8da3(a)news.astraweb.com...
>
> > It is discussed on the website (http://www.physicsforums.com)
> > recently as this year.
>
> > I see some problems with the idea as argued. They keep talking
> > about wind speed with respect to ground speed as if that is a
> > power generator. They also seem to be pretending that gearing, or
> > the difference between wheel and propeller rotation speeds, is
> > somehow a power source.
>
> That's exactly how it works. The maths proof of how it works and a solution
> for the conditions under which it works is also out there on the web. A land
> based version was recently built and tested. It achieved more than twice the
> wind speed. See Youtube. I believe the first working machine to do it was
> built in the 1960's.
>
> > The follow-on argument appears to be that you can sail directly
> > into the wind.
>
> Also possible and has been demonstrated many times, including on full size
> boats.
>
> > I see no prior discussion here on UseNet. On the Internet, I see
> > it is discussed as early as 2007. Apparently the idea was
> > originated by Jack Goodman in 2006.
>
> This has been discussed a million times on different forums. .
>
> Aside: America Cup yachts manage to sail between two points (one directly
> downwind of the other) faster than the wind by "tacking" downwind.  If they
> can do it the rest is just engineering.

-----------------
about "sailing agisnst the wind'
it is an illusion!!!
as usual mathematicians are discussing
'paper discussions ''
on issues tha they never experienced
in reality!!
th ereality is
that
**the wind is never steady in just one exact direction
it is always do some swirling movement

now the sail is not as 'innocent as you immagine
it is built as
on one of its edges you have the stiff mast
while onthe otherr edge of the sail
you have a flexible cable
bottom line
youget a sort of a push selector
that accumulates manulty the push force
on th e mast
and nearly neglects the force
in the cable !!
now together with the steering system
you can direct the boat to the desired direction!!
2
in addition to that
the boat is moving in a zig zag line
against the wind
one thing is sure
sailing at those times
was much more knowledgeable and exciting
than in our boring days (:-)
not 0nly the technique
but discovering new unknown lands
and continents as well !!!
our days it van be done
in science as well (:-)!!

Y.Porat
-------------------


From: Tom Roberts on 1 Aug 2010 08:16
Y.Porat wrote:
> about "sailing agisnst the wind'
> it is an illusion!!!

You know as little about sailing as you do about physics or math -- i.e. NOTHING
AT ALL.

There is no "illusion" about sailing upwind, and sailors do it all the time. Not
directly upwind, mind you, but a good boat and crew can approach 45 degrees from
directly upwind. Using alternate tacks the boat can have a long-term path going
directly upwind.

BTW a modern sailboat on a reach can sail considerably faster than the wind. But
no boat can do so when running before the wind.

If you don't know what these terms mean, look them up. They are
standard sailing terms.


Tom Roberts
From: bert on 1 Aug 2010 08:57
On Aug 1, 8:16 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote:
> Y.Porat wrote:
> > about "sailing agisnst the wind'
> > it is an   illusion!!!
>
> You know as little about sailing as you do about physics or math -- i.e. NOTHING
> AT ALL.
>
> There is no "illusion" about sailing upwind, and sailors do it all the time. Not
> directly upwind, mind you, but a good boat and crew can approach 45 degrees from
> directly upwind. Using alternate tacks the boat can have a long-term path going
> directly upwind.
>
> BTW a modern sailboat on a reach can sail considerably faster than the wind. But
> no boat can do so when running before the wind.
>
>         If you don't know what these terms mean, look them up. They are
>         standard sailing terms.
>
> Tom Roberts

No matter which way the wind blows he sets his own sail. He can set it
to go faster than the wind blows.He is the master TreBert
From: Hayek on 1 Aug 2010 09:51
Tom Roberts wrote:
> Y.Porat wrote:
>> about "sailing agisnst the wind'
>> it is an illusion!!!
>
> You know as little about sailing as you do about physics or math -- i.e.
> NOTHING AT ALL.
>
> There is no "illusion" about sailing upwind, and sailors do it all the
> time. Not directly upwind, mind you, but a good boat and crew can
> approach 45 degrees from directly upwind. Using alternate tacks the boat
> can have a long-term path going directly upwind.
>
> BTW a modern sailboat on a reach can sail considerably faster than the
> wind. But no boat can do so when running before the wind.

Are you sure ? Sometimes you can go faster by slightly
downward tacking. Especially if you follow wind shifts,
also a supreme tactic when going upwind.

I remember they laughed at my compass. When I beat them
for the first time, they all ran at the shop and
installed one too. (Laser class)

Uwe Hayek.

>
> If you don't know what these terms mean, look them up. They are
> standard sailing terms.
>
>
> Tom Roberts


--
We are fast approaching the stage of the ultimate
inversion : the stage where the government is free to do
anything it pleases, while the citizens may act only by
permission; which is the stage of the darkest periods of
human history. -- Ayn Rand

I predict future happiness for Americans if they can
prevent the government from wasting the labors of the
people under the pretense of taking care of them. --
Thomas Jefferson.

Socialism is a philosophy of failure, the creed of
ignorance, and the gospel of envy, its inherent virtue
is the equal sharing of misery. -- Winston Churchill.
From: Y.Porat on 1 Aug 2010 10:57
On Aug 1, 2:16 pm, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote:
> Y.Porat wrote:
> > about "sailing agisnst the wind'
> > it is an   illusion!!!
>
> You know as little about sailing as you do about physics or math -- i.e. NOTHING
> AT ALL.
>
> There is no "illusion" about sailing upwind, and sailors do it all the time. Not
> directly upwind, mind you, but a good boat and crew can approach 45 degrees from
> directly upwind. Using alternate tacks the boat can have a long-term path going
> directly upwind.
>
> BTW a modern sailboat on a reach can sail considerably faster than the wind. But
> no boat can do so when running before the wind.
>
>         If you don't know what these terms mean, look them up. They are
>         standard sailing terms.
>
> Tom Roberts

------------------
and i said similar thing
and even more than a chemist can know !!
and dig out as a parrot crook from the net...

about the structure of mast etc
your impertinence is much bigger than your
personality
Y.P
--------------------------

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