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Old August 26th 06, 01:24 AM posted to rec.aviation.piloting
RST Engineering
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Posts: 1,147
Default Koch Chart Formula

Sorry, I wasn't aware I was teaching freshman high school Algebra 1 here.
The "final product" is a series of four equations, two for fixed pitch and
two for constant speed propellers. I will derive/illustrate the first one.
It is left as an exercise for the student to complete the other three
(hint -- you only have to change one number in the equation).


D = Density Altitude (from the prior equation).

TD = Takeoff Distance at D

TS = Takeoff Distance at sea level

% = The percentage increase figures from the prior document.


For example, for a fixed pitch propeller:

TD = TS * (1 + ((D / 1000) * 0.15))

Jim


"abripl" wrote in message
oups.com...
Your function was for Da = f(Pa, T) which in turn require various
approximations to get takeoff distance and climb performance - not a
finished product.

I may try again later to get a better empirical function - not
impossible.

RST Engineering wrote:
did you not get the exact equations I posted here two days ago?

Jim