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**Sea Wasp (Ryk E. Spoor)**

On 11/2/16 8:20 PM, krw wrote:
On Wed, 2 Nov 2016 02:54:54 -0000, wrote:

In sci.physics krw wrote:
On Wed, 2 Nov 2016 00:00:54 -0000, wrote:

In sci.physics John Larkin wrote:
On Tue, 1 Nov 2016 18:19:02 -0000, wrote:

snip

BTW, the lack of commercial success for flying cars has nothing to do
with propulsion methods.

But propulsion does matter, in the sense that there is no affordable
way to make a flying car. Helicopters get terrible gas mileage.

You do know helicopters spend a fair amount of time not traveling, don't
you, but that has nothing to do with flying cars.

Cars spend a fair amount of time not driving, too. So?

Not at close to full output power.

Helicopters don't have a throttle or an "off" button?

I think he refers to the fact that a rotorcraft uses ~70% of its
available power just to hover -- i.e., before it's even moving forward,
or carrying any cargo beyond its own weight, it's starting to approach
max output. In addition, current torque monitoring systems for
rotorcraft are only accurate to about +/- 5%, which means that in
practice the pilot is going to have to be real cautious about exceeding
95% output. A heavily loaded rotorcraft will be limited to a VERY small
percentage of its power output for actually moving anywhere.

--
Sea Wasp
/^\
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