On Monday 12 June 2006 19:47, dene maxwell wrote: > Unfortunately the data kept by FAA/CAA or what ever the local > administration is called is often out-of-date or just plain wrong. > Experience of the last month has taught me that. Poring over aerial photos > and current third-party documentation has shown significant discrepencies. Keep in mind that those FAA/CAA diagrams are being used in real aviation right now, not the aerial photos or third-party documentation. While I would not rule out that that those airport diagrams may contain errors, I am more certain that the aerial photos and third-party documentation you mentioned are the ones that are wrong.
> Dumb is a very subjective assessment, agreed it is time-comsuming, but is > sometimes necessary to get not only positioning correct but also surface > type. The positioning would be correct as long as the lat/lon information on the aerial photo is correct. If those lat/lon information is incorrect, then all those time spent on positioning would be wasted. > I seem to remember a while ago I provided examples of CAA airport > documentation for conversion into SVG format and it couldn't be done > because the color scheme used was not what the automated process needed. I > am not aware of any numerical description available that would solve this. > It is really great that you have managed to get this working for FAA > diagrams ... It will be even better when it can be applied globally. It could be done. It just that I "hardcoded" the color information into my script, and was too lazy to alter it just to prove that it would work for CAA airport diagrams. > >2) Lat/Long information is in the diagram itself. > > Generally the lat/long information in the FAA/CAA diagrams is too coarse > for some uses. I am currently doing AI flightplans and need to get Lat/long > for touch-down points, braking points, and taxi-ing points. TaxiDraw > provides this 6 decimal places. The FAA diagram doesn't. So what? Users like you and I generate those 6 decimal places, from aerial photos and third-party documentations that have incorrect lat/lon information. Who have better access to those information? Us or the authorities? > IIRC the French > CAA diagrams don't even have lat/long references apart from the various > navaid locations. Yes they do. Ampere _______________________________________________ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
