On Fri, 18 Jul 2003 20:30:15 -0400 "Norman Vine" <[EMAIL PROTECTED]> wrote:
> Richard A Downing writes: > > > > I'm working my way through some of the UK aerodromes, and have hit > some problems agreeing ANY of the decimal coordinates > > in the FG files with the DMS coordinates given in the UK AIP. > > probably worth while reading this just to > make sure you have the 'maths' right > http://www.gps.gov.uk/guidecontents.asp > > Norman Norman, Thank you very much for this excellent reference - I don't pretend to have absorbed all of it at first reading - there is so much there! The UK AIP defines its Geodetic Reference System as WGS84. Many of the reference points in the AIP have been established by survey, but some by mathematical conversion (and are marked with an asterisk to show this) (See UK AIP GEN 2-1-2 (31 Oct 02) section 3). I guess this means that continental drift will be an issue as well as the conversion matters referred to in the document you referenced. Curt's document: http://www.flightgear.org/Docs/Scenery/CoordinateSystem/CoordinateSystem.html states that WGS84 is used in FlightGear. Although this has moved my understanding forward, I still don't know where the coordinates in FG's database came from. I recollect seeing something about imports from X-Plane, but I can't find the reference. I also need to do some more thinking. Richard. _______________________________________________ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
