Good Morning!!It's my birthday, I feel great to see another one come by and I wish all of my friends at AVSIM a beautiful weekend!!Now, the topic.When I have positioned the various lights on an aircraft such as in this example for the DC-3:light.0 = 3, -09.90, -44.98, 2.60, fx_navredhI realize that these numbers reflect the position of the light in relation to a central fixed point in the aircraft (i.e; -09.90 back; -44.98 to port, and 2.60 up )What I really wish to know are two things:1) Is this central "fixed" location the COG (Center of Gravity) ?2) Are these units of measure in feet?My reason for asking is because I am manually putting together a data file for the load points for a DC-3 Airways version of the DC-3 (fewer but larger seating). If these units of measure are in feet, it will help me greatly in figuring some things out.Cheers Y'all! :DHeather

Heather, Have a Very Happy Birthday and many more of them! Unfortunately, I have absolutely no knowledge to help answer your question. Someone with more batteries in their flashlight than I is bound to show up shortly. Enjoy your day! Best regards, JackD

Thank you Jack! :DIt's funny how most people, as they get older, and especially women, despise seeing another birthday. But my oh my how a serious medical problem can radically change your attitude on that!I'll take all I can get and hope to see thirty or forty more of them!I am in a fantastic mood and I don't even take drugs!! Hope it lasts a while. Cheers!Heather

The number are in ft. For instance, the MD-83:&l;WEIGHT_AND_BALANCE&r;max_gross_weight = 160000.000empty_weight = 79686.000reference_datum_position = 77.000, 0.000, 0.000empty_weight_CG_position = -74.000, 0.000, 0.000max_number_of_stations = 50The designer of this model used a more conventional aircraft designer's method of labelling the reference point at the nose of the aircraft or a point in front of the noise. The empty weight CG position is 74ft from the nose.The B737-400:&l;WEIGHT_AND_BALANCE&r;max_gross_weight=148500 // (pounds)empty_weight=110792 // (pounds)reference_datum_position=0, 0, 0 // (feet) distance from FlightSim Reference position: (1/4 chord, centerline, waterline)empty_weight_CG_position=0, 0, 0 // (feet) longitudinal, lateral, vertical distance from specified datummax_number_of_stations=50This design uses the Microsoft version of visual center reference point. See the FSEdit_SDK.exe from http://zone.msn.com/flightsim/FS02DevDeskSDK00.asp for more info on the reference point.The reference point is arbitrary, but once selected, all measurements must be made from that point.Happy Birthday!!!