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Comment by zackmorris

Here's the best resource that I know of for building ion wind "lifters":

http://jnaudin.free.fr/lifters/main.htm

So far their best result is 0.886 kW/kg (0.539 hp/lb), comparable to a helicopter, by using a pulsed DC power supply at 70 Hz:

http://jnaudin.free.fr/html/lftphv.htm

So a helicopter with that could lift 1.13 kg/kW (1.86 lb/hp).

A plane with a 10:1 lift to drag ratio would fly with 0.0886 kW/Kg (0.0539 hp/lb). It could lift 11.3 kg/kW (18.6 lb/hp).

A 200 kg (440 lb) helicopter, including human passenger, would take 177 kW (237 hp).

The same mass airplane would take 17.7 kW (23.7 hp).

Of course the pulsing would add a buzz which may not be desirable. It looks like the pulsed DC uses 17.72 RMS W vs 69.58 DC W, so is about 3.927 times more efficient than DC. Maybe a plane could have both silent and high efficiency modes for takeoff and cruising.

I have no idea how these numbers compare to the ones in the article, but they should be within the same magnitude. Please someone double check my math :-)

parent zackmorris 8 years ago

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