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Old February 6th 11, 01:17 AM posted to rec.aviation.military,rec.aviation.piloting,rec.aviation.homebuilt
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Default Taxi calculator? (propeller type and speed, aircraft weight, taxi speed)

On Feb 6, 1:33*pm, John Doe wrote:
heirophant wrote:
John Doe wrote:
heirophant heremypants hushmail.com wrote:
*John 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...