Google Earth gives flight control a new dimension
- By David Essex
- Oct 03, 2006
Much of AFF's pizzazz comes from Google Earth Pro client software, which Google calls the most popular 3-D program in history, with an installed base of 100 million.
It's the same software that caught on like wildfire last year with home users and television news programs, who used it to zoom down from simulated space to peer at pictures of neighbors' suburban rooftops and the mean streets of Baghdad. Its technical claim to fame is its ability to move a graphical representation of the Earth smoothly in response to user commands, even when the data feed has slowed down, according to Brian McClendon, a Google engineer.
The client software talks to Google Earth Fusion Server software that aggregates vector and raster terrain data with aerial imagery.
'The combination of the two is what makes Google Earth look like it does,' McClendon said. AFF adds positional information beamed to a satellite from Global Positioning System devices aboard aircraft.
By implementing Google Earth, federal firefighters graduated from flat, 2-D maps to 3-D maps that more clearly display terrestrial features, such as all-important elevations that help predict a fire's speed and direction. Detailed notations and data from third-party sources make the maps even more informative.
A key enabling software technology is Google's Keyhole Markup Language (KML), named after a company it acquired. KML is a 'grammar' of the Extensible Markup Language, the Web's data standard. 'It's a way to sort of annotate the Earth,' said Google's Noah Doyle.
The Forest Service also cites Google's KML-based Network Link technology as crucial to AFF's success, saying it manages the secure HTTP connections between aircraft GPS hardware and the servers.
FBOWeb.com, a site that lets individuals track the locations of commercial flights to within a second or two, is a good example of a Network Link application, according to Doyle. He likens the technology to the Really Simple Syndication (RSS) feeds that employ XML to monitor Web sites and send updates to users.