Air route maps

[kmusser]

Today a bit about air route maps. I've made a bunch of these for Wikipedia and I have to admit I'm a bit sorry I did because they are a pain to keep updated. But anyway, I thought it would be neat to be able to visualize all the non-stop destinations from a given airport - a quick way to show that airports reach.

The maps are relatively simple, just outlines of the countries and dots for the locations. Country borders are available from a variety of public domain sources and my mapping software can convert a list of latitude/longitude coordinates to dots. I debated adding lines between the cities like they do in airline magazines, but they just made the maps harder to read. Compiling the lists of destinations is the somewhat time consuming part, the airport articles have a list, but I quickly learned those weren't to be trusted. Some airports will maintain a list of destinations on their website, but most do not, so I'd need to visit individual airline web pages and track down their timetables and then look up the coordinates for each destination.

These are also among the few maps where I mess with the map projection. All maps have some distortion that comes from trying to portray a 3-D object in 2 dimensions, generally they'll have a center line that is accurate and distortions will increase from there and different projections will minimize different kinds of distortion. For most maps I'll use an equal area projection - those keep the size of areas correct in exchange for a bit of distortion in terms of shapes and directions - if I'm doing a map for graphic visualization rather than actual navigation that's usually what I want. For these I switched to a Azimuthal equidistant projection which centers on a point rather than a line and keeps directions and distances from that point correct while distorting shapes and sizes so straight lines on the map going out from the airport would be straight lines for an airplane as well.

So the problem with these maps are 1) while I think they look ok at full size, they really aren't all that great at the size they're actually used in Wikipedia articles. The labels are too small to be legible, and most airports have too many destinations too close together for me to increase the size significantly. 2) airport destinations are far more fluid than I ever realized, the maps are out of date almost as soon as I make them. I've settled on updating them every year or so if they're still in use.

The map below is one I just updated for Panama City's Intl. airport, it's interesting in that it's exclusively Intl. and it's often used as a transfer point between North and South America, so it has a broader reach than would be usual for a city of that size. The two European destinations caused a problem in that if I put everything on the same map, the Caribbean area with most of the destinations was too small to see properly, so I made an inset with a more standard projection for Europe.

Comments

[zammis.livejournal.com]

it would be interesting to see if you could somehow automate the process with a lookup of destinations. I wonder if Kayak would work, or perhaps an API that uses Kayak? Like SABRE (the software travel agents used to use/still do?)

[cosmolinguist]

This is so cool. Looking at a thing like this map, it's easy to never stop and consider the effort and techniques and time that go into it. Thanks for reminding me (and this is the kind of dorkish thing that interests me, now that I've moved to somewhere far-flung from the stuff I was used to seeing on maps...I've seen good old AMS a lot more than I might have liked! :))