Hi, IIRC you can specify functions (e.g. tables) in JSBSim which are in a first step completely unrelated to lift, drag, sideforce or any of the moments. The files output by DATCOM+ do this for the ground effect by establishing a table of additional coefficients based on the ratio of height AGL and span. These coefficients are then multiplied on the basic lift and drag.
Simply place a function outside any of the axis definitions and then use it as a property in your axis functions. An example can be seen in the Seneca-model by Torsten Dreyer: http://cvs.flightgear.org/cgi-bin/viewvc/viewvc.cgi/data/Aircraft/SenecaII/SenecaII-jsbsim.xml?content-type=text%2Fplain&view=co Search for "ground-effect-factor-lift". You could use this to describe the downwash based on the current AoA and whatever is needed in addition. Cheers, Ralf ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2005. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel