Since I put together the Google Earth animated flights from USA airports (more of those coming up soon!), I’ve been meaning to check out the same thing without the time element - a KML file where routes only display as you hover the mouse over various airports.  Essentially a Google Earth, 3D equivalent of those interactive flight maps you see on airlines’ websites. 

As a side effect it does create some navigation difficulties,  but I still think it makes a lot of sense to de-clutter the screen, without forcing the user through a series of menus or pop-ups. More importantly, the effect is actually fairly straightforward to achieve using KML’s <StyleMap> entity. (Check this out for a good description of how it works.)

So, what I’ve done is applied mouseover effects to a (near) complete route map of scheduled flights within the UK, Ireland, Channel Islands and Isle of Man.  That’s about 800 one-way routes, between 69 airports.   Download the file here:

UK and Ireland Flight Map(250kB)

• The Placemark balloons include information about airlines and destinations.
• Labels follow Wikipedia’s convention of using place names rather than real airport names.
• Routes are displayed with  exaggerated altitude.   Still need to do a bit of work to get the balance of these right:  check out some of the hair raising journeys between the Orkney Islands (NE Scotland). 

One downside of GE’s highlight mode is it doesn’t stay switched on a after a mouse click.   However, there are a few navigation tricks that allow you to keep routes displayed and move around …

• Click the middle mouse button on an airport icon, and hold it down while moving the the mouse.
• Hover the mouse pointer over an icon, then switch to keyboard control  (cursor keys,  shift + cursor keys, Page up/down, + key, - key,  etc…).
• Click on an airport icon, quickly drag it and let go. Just as you would to set the Earth rotating.

The source data for all this is scraped from the Airport pages on Wikipedia, and compiled using a lot of Perl scripting to scrape, mash and meld it into KML.  Obviously its never going to be 100% reliable, but at least it should be pretty easy to keep the file regularly updated, and expand to other parts of the world.