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p10ppy

A little FM tool

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Here's a little toy/tool I did up a little while ago when I got sick of big excel spreadsheets

 

 

fmtool.gif

 

 

Run it (from any where) and feed it FM data.ini's and it crunches them up into a simplified form for analysis (only, no editing, no saving, no pain)

Up to 5 AC at a time

 

I found it useful for comparing FM's and finding any big mistakes

 

Mostly it just works with the info in the ini, but you will need to provide a aircraft length and wing configuration (mono,bi etc) for some of the Loftin/moi calculations

 

It totals things like CD0 for the aircraft and gives an overall coefficient and supplies the equivalent Loftin based estimate. (Simplified to full power at sealevel,dry weight)

 

Moi estimates are based on a combination of existing 3rd wire aircraft and the formulas from Charles's SF notes (thank you Charles and Abacus)

 

The Moi's get wildly wrong with the BIG aircraft, and all the existing stock FE craft are watercooled biplanes so it is really are only indicative ballpark stuff

 

In fact all the Loftin based estimates are very rough but good enough for government work imho :wink:

 

Note: I'm using Cdi (induced drag) from the Loftin calcs for CDL in the ini, and I don't know that they are really equivalent

It's the one major difference in value between the stock aircraft data and the derived Loftins

 

At the bottom there is some derived info on wing/power loading etc that might be useful for gauging performance

 

I'm not the greatest coder so it's a bit slow when it comes to the data crunch

And I have not done much error trapping so I'm sure its easy to break(wont hurt the ini files tho) :blush:

 

It will output to a default printer but only as a bitmap so its not real sharp

 

Hope someone finds some use in it

 

Suggestions are welcome

 

Get it from combatace once its been approved

 

 

 

For more info on how Loftin estimate's

 

http://www.hq.nasa.gov/office/pao/History/...68/contents.htm

Appendix C

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Can you explain the color code system its using? Are blue or Red text telling me a problem exists?

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yeah sorry :blush:

 

blue means the highest value across the range of AC, red the lowest (note sometimes the lowest(red) is better)

black is in the middle

 

Green means a number that is using data not in the ini (ushally a loftin base estimate, with a seperate algorithm)

 

if its not green its derived and summed from the ini

 

hmmm not sure that was very clear :blink:

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Guest Charles

Nice work, thanks.

It is very useful to be able to compare FMs visually, especially across a range of them.

This should be useful.

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