I'm not really happy with the labels in GE, so the points are not labeled, and those need to be added in photo-editing software after saving the image (if you want them labeled). If you want to learn more about KML, this is a good starting place, too. Simply replace the numeric coordinates with those for your project. KML files require altitude in meters, so don't forget to convert MSL altitudes in feet to meters.īelow is a KML file for the last three waypoints of the N23 RNAV-7 approach (Sydney, NY). Longitude is positive east of Greenwich, so airports in the CONUS will have negative longitudes. There are lots of online explanations of how to make this conversion.Ĭoordinates are entered in the KML file as three numbers separated by commas: longitude, latitude and elevation. This can be tedious without some sort of computer program and that's beyond the scope here. Note that the FAA seems to compute descent angles using the elevation at the runway end or threshold - not TDZE.įAA publishes lat/lon data as degrees, minutes and seconds, but KML requires decimal degrees and so the FAA data must be converted - a precision of 6 decimal places s/b adequate. Be sure to add the TCH to runway end elevation if that's important for the image. If there is a displaced threshold, those coordinates are also published as "DT Latitude", etc. In most cases, the elevation of the runway end should be used, not the published TDZE. Presumably, you're wanting the coordinates at the end of a runway, and these are listed for all runways. The current URL for this page isīut that may change, so use the online search if the link doesn't work.įor airports, search online for "FAA Airport Database", and the current link for this is ![]() For waypoints, search online for "FAA Waypoint Database". Or just a plain old calculator will do in a pinch.Ĭoordinates and elevations should be obtained from the FAA. ![]() Some of this, especially coordinate calculations, will be easier with the aid of some kind of scripted computer programming application, such as perl, excel, python, octave/matlab, etc. Some folks wanted to know how to create a KML file like this, so here's the method I used. As part of a discussion of an accident (see here ), I created a KML file for Google Earth (GE) which depicts the waypoints on an instrument approach in 3D to better visualize what some of the issues are with the approach.
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