Paul - I have a BASIC program that predicts performance pretty
 well and it computes induced drag, uses prop diameter, airfoil

tables

 wing span,shape etc. The 2G is easily modeled by increasing
 gross weight by twice. Weight is a minor player in top speed,
 and the turns in the F1 class course are a larger factor than on
 the unlimited course. It took F1 guys a long time to get the
 message on aspect ratio. Acceleration is also a factor in F1, but

not

so

 much in unlimited with the paced start.
 If you like I could run some straw man cases for you. Vance

Jarrett Johnson wrote:

Vance, I'm curious to know a bit more about your program. Did you

write

it

or purchase it from someone else? I'm looking for stuff like this

and

had to

ask.

Jarret - and others. This is a program that I first wrote back in Apple

II

days,
and has been growing as more computing powr becomes available.

Unfortunately

it is written in BASIC (really GWBASIC) and I am not even sure that it

will

run in QBASIC without some cleaning. It calls a file that describes the
plane
that is prepared with a DOS editor - such things as wing area, span,

weight,

engine power, fuselage area, drag coeff, struts, wires, wheels, faired?
or retracted - etc, and then calls another file for airfoil

charactersitics.

It steps through speed from stall ,computes drag ,rate of climb, and top
speed when climb becomes less than zero. Like any model.you can lie to
it , but if you are truthful it does a decent job. I have to run it on

an

older
version of windows that lets me talk DOS, and use an old "waterwheel'
printer that can act like a DOS list device. I am trying to learn Visual
Basic to move it over but my old ossified brain cells are rebelling.
Vance

 Vance - It sounds like this program would be a candidate for converting to
a spreadsheet. I would be willing to create an Excel Spreadsheet from your
program.  If the airfoil characteristics are available on a website I can
write a visual basic macro to automatically download the data, parse the
data,  and do the calculations.  I have also written macros that can
optimize up to two variables and plot a surface map showing the interaction
of the variables.  Please let me know if I can help.
You can email me directly at lmorosz@myacc.net .
Les

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