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View Full Version : Question flight trim simulator??


jay flay tway
Jul 20, 2005, 08:05 AM
Does anyone know if something at all like this exists?

A program, like a simulator but for learning about how each of all the variables affects the flight of an airplane. You could adjust all the variables independently and see what it does to the flight and it would give numerical values like speed, ascent, etc.

I'd love to have something like this...
or, failing that, a very concise and complete explanation for a standard model.
I've been flying planes off and on for quite some time and feel like i've learned so much but still draw a blank about certain adjustments. Here's one for example.

7-inch span free flight rubber plane (Ikara Butterfly). tip dihedral only. single-surface wings, about 2.6 grams, design cg at about 65% back from the LE.
flies at about 2 or 3 miles an hour i think at very high incidences. tail lifts in normal flight too.

Here's the question: What does giving the main wing more incidence do to the flight (at equilibrium)? I can't seem to see enough difference consistently to know for sure. Maybe I just lack the necessary patience to do enough testing.

It'd be great to plug it all into a sim and get the answer in numbers and/or visually.

Ollie
Jul 20, 2005, 10:53 AM
The plane's pitch attitude with airspeed is angle of attack (AoA) not incidence.

A wing has AoA due to airfoil and added AoA due to induced AoA. The induced AoA equals (Cl^2)/(pi X AR). For a wing with a very high aspect ratio (AR) near stall have 8 to 10 degree total AoA. For a wing with a very low AR near stall have a 20 to 30 degree total AoA.

See:
http://aero.stanford.edu/WingCalc.html