Vance Jaqua wrote:

Paul - I have printed it out to explore it at my
liesure, and will comment then - I use both Quick
BASIC
and a regular BASIC related to BASICA for most of my
programming - but I am so old fashioned that I use
line numbers in QB - I have a propeller program that
tries (fairly well) to actually predict prop
performance on a particular engine at varying flight
speeds all the way
down to static. It uses a combination of momentum disk
and strip element theory with a table od genaric
airfoil performance for lift and drag. it starts with
an estimated velocity thru the prop for a given rpm
and flight speed and compares thrust from momentum
with the summation of thrust lift from the elements
with that angle of attack. Then iterates on the
velocity until they match. Required shaft power comes
back from the strip calcs as well and is compared to
the power curve - and it starts changing rpm and
repeating the iteration - thousands of loops - but
with modern PC's it does it in seconds even in slow
BASIC. The prop is described by dia, and either true
helical pitch or you can set the angle of the zones.
It assumes 2 blades so for more you put in a total
equiv width at the zones. You guys are welcome to have
it tho I never consider it finished, and am always
toying with it. It could probably be transported as an
asci file - Vance

Sounds a lot more sophisticated than mine.
Send it along in ASCII Vance. I will strip the un-needed 
line numbers and replace the GOSUB 6789 with GOSUB
"Descriptive Labels". I hope it is commented but
I will take it never-the-less.. 

Paul Lamar
 
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