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View Full Version : Get aeroplanes and conveyors banned, but wait - -



R2x1
31-08-2010, 06:39 PM
Just when you have formed a theory on the aircraft and conveyor belt theme and started to sleep properly at night, these clowns (http://www.wired.com/autopia/2010/08/ddwfttw/) declare it is possible to travel downwind faster than the wind speed in a wind powered vehicle.
Think about that in the abstract for a while.
After declaring it, they apparently thought the argument could be finally ended if they went and demonstrated it.

Strong drink not recommended before reading the link.

bob_doe_nz
31-08-2010, 07:57 PM
Not this frakking theory again!

Just use a single engine Cessna and be done with it!

SoniKalien
31-08-2010, 08:04 PM
Wouldn't going faster than the wind create a vaccum in the sail? Which means negative pressure, which means (roughly) drag.
I can't see for the life of me how this is possible, even taking resistance out of the equation. :waughh:

Erayd
31-08-2010, 10:02 PM
It's quite possible - the article that R2 linked explains it quite well, but feel free to ask questions if the concept confuses you :).

:pf1mobmini:

SoniKalien
31-08-2010, 11:51 PM
Ok I think I get it now...

beeswax34
01-09-2010, 12:53 AM
Yup, they showed this in a documentary recently. Quite possible as Erayd said

Greven
01-09-2010, 06:56 PM
I didn't think it would be possible for the wheel to produce enough power to run that big propeller, but they managed it :stare:

I wonder if they could make it work from a standing start by using a generator that doesn't kick in until they reach a certain speed?

Erayd
01-09-2010, 07:34 PM
Edit: Never mind, redundant post replying to someone who's original post I misunderstood. Mods feel free to delete this one ;).

Erayd
01-09-2010, 07:58 PM
I wonder if they could make it work from a standing start by using a generator that doesn't kick in until they reach a certain speed?It already does work from a standing start:


...look at the video above that was taken by Richard Jenkins. We start from a dead stop with no assist...

Greven
01-09-2010, 08:07 PM
ah. perhaps I should have watched the video.