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c172p-team / c172p

A high detailed version of the Cessna 172P aircraft for FlightGear
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FDM: Airfoil lift / drag data #1244

Closed legoboyvdlp closed 5 years ago

legoboyvdlp commented 5 years ago

@dany93 I found that the airfoil which the Cessna 172P uses is the NACA2412.

See http://www.airfoildb.com/airfoils/356 for a lift polar / drag polar.

I have four or five documents here that might help in some way to improve the FDM:

legoboyvdlp commented 5 years ago

WindTunnelTestsonaModelCessna.docx Report.pdf FULLTEXT01.pdf aerodynamic-performance-of-the-naca-2412-airfoil-at-low-reynolds-number.pdf 27.pdf

dany93 commented 5 years ago

Thank you @legoboyvdlp

There are large discrepancies between these documents... As usually. Some are doubtful ( Report.pdf : Lift coeff value, negative or null at zero alpha ??). Or measured at much too low Reynolds number.

The current values are those selected by Megginson (at my knowledge), and they seem correct from my point of view. As I don't see what is wrong in the behavior, I don't see why it must be changed. Even less how it can be improved by considering publications with so scattered values or unfit numbers.

See airfoils.com.

HHS81 commented 5 years ago

I agree to dany93. It seems to me a common misbelief, that the windtunnel data of an airfoil alone can help improve a JSBSim aircraft.