"Grimly Curmudgeon" wrote in message
...
We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember ThinAirDesigns
saying something like:


Initially the wind merely starts blows the vehicle downwind. Once the
vehicle is moving the wheels provide the input torque to turn the
propeller. The propeller takes wind that was moving at say 10mph
across the ground and pushes back on it until it is only moving say
5mph across the ground. The energy removed from the wind when it is
slowed is the energy powering the vehicle.

Light dawns. If you'd mentioned pusher prop at the start...

Ok.

So they are travelling at 2.9 times the speed of the wind, no prop
They need to slow the wind as currently they are speeding it up through
drag.
Start prop.. now they have to accelerate a mass of air to greater than 1.9
times the real wind speed before the real wind starts to be slowed.
Does it take more energy to accelerate it to 1.9 times the wind speed than
they get by slowing the real wind down by less than 1?

The claim does not make sense even before you add in friction, turbulence,
etc.


My gut feeling is it would be heavily dependent on very low frictional
losses in the transmission of whatever type.
Permanent Magnet bearings? Air bearings need an input.

WD40?

Does WD40 do magic too?

Anyway as far as I am concerned this thread id dead, other people can
believe it if they want, nothing in the videos explains it.