FAA subscription data includes .shp (shape) files for ESRI products. Google Earth Pro ($400/year) is capable of opening these shape files directly, but the default setting is to make them opaque. Thus the class B airspace looks like one single area with no details. FWTools is a free open-source conversion tool to change GIS formats. It also does a much better job of converting the data, showing each individual airpspace and its low and high altitudes. The FAA marks the class E files as experimental, NOT TO BE USED FOR NAVIGATION.
The FWTools command to change from the FAA's .shp format to KML is as follows:
ogr2ogr -f "KML" C:\airports\class_b.kml C:\airports\class_b.shp The FAA lists airspace in order (e.g. Washington Class B Area A, Washington Class B Area B...), and fwtools maintains this order. When Google Earth displays this information, the last one listed goes on "top" of the area. Thus when you click on the center of a Class B zone, the widest area comes up, NOT the SFC to 10000 area. You can see the correct area when you click on the corresponding area layer, however. (I am currently working on a fix for this, but it requires some custom XML and SQL programming that's going to take some time.)
However, there is a weakness in Google Earth. The KML specification does not allow the creation of floating polygons. All non-plane polygons are extruded from the surface or ocean floor. Thus, there's no way to express in KML the upside-down-wedding-cake shape of your typical Bravo airspace. This may one day change, however, because Google is already adding its own extensions to the KML specification.
If you don't want to bother, just download the Airpspace KML files here: Archive link.The usual warning applies -- DO NOT USE FOR NAVIGATION. The KML archive is here.
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