"Flaps_50!" moreflaps gmail.com wrote:

John Doe j... usenetlove.invalid wrote:
heirophant heremypa... hushmail.com wrote:
John Doe wrote:
heirophant heremypants hushmail.com wrote:
ÿJohn Doe wrote:

Is there such a calculation/formula? How can you tell what
propeller to use, how fast it should rotate, and how much
weight it can push along the ground?

Specifically... I would like to tell what sort and size of
propeller rotating at what speed, in calm air to push 100
or 200 pounds on smooth and level pavement with zero
rolling resistance to about 20 mph.

Far too little information to arrive at an answer. Could
you tighten the variables a bit?

What other variables do you need?

How quickly do you wish to reach Xmph,

Five or ten seconds.

what would you allow for maximum efficiency of the propeller

Whatever type of propeller is best for taxing purposes.

and what are the limitations of your power output to the
propeller,

None. The propeller spins that whatever RPM is needed.

and are we rolling or standing start?

Standing.

I suppose the wind resistance of a typical light/small aircraft
on the ground would be in the ballpark.

Ignoring rolling resistance, look at the power consumption of a
plane at cruise, then note that aerodynamic drag could be
estimated to follow the square of speed. So, if 100 HP- 100 mph
then 10 mph = 1 HP. Rolling resistance is the biggest factor
though as you should know...

My experience suggests that wind resistance at speed is
significantly greater than rolling resistance.
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From: "Flaps_50!" moreflaps gmail.com
Newsgroups: rec.aviation.military,rec.aviation.piloting,rec.av iation.homebuilt
Subject: Taxi calculator? (propeller type and speed, aircraft weight, taxi speed)
Date: Sat, 5 Feb 2011 17:17:56 -0800 (PST)
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