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There are 13,632 airports in the FAA database. That does not count balloonports, seaplane bases, gliderports, heliports, or ultralight facilities. That's also a huge number of placemarks for a KML file, so your Google Earth machine will need some processing power.

If you pan out, the placemark icons will cover the continental United States. It also drives home the point that if you're flying high enough and your engine dies, you should be able to glide to an airport.

Improvements: Public airports are in blue; private airports are in red. AWOS data is included where applicable. (If airports have an AWOS, it's included. Note that ATIS is not the same as AWOS.)

Code improvements: All output code is Python. The database is still Microsoft SQL, and the API is adodb for Python. Next: Porting output code to Linux (need a new database connection) and keeping back end MS SQL for now. Long-term: cleaning up and uploading data via python into MySQL.

Random Comments on Python: String manipulation in python is the same as in visual basic script, but different. If statements have no end, just an indent and and end of indent.

The KML file is in the KML archive, as usual. DO NOT USE FOR NAVIGATION.

The US Government makes available many data sets free. This is in contrast to the UK where public government data is the property of the crown and is sold to the public. US citizens still pay for the data in taxes.

One of those data sets is Radiological Air Samples from the US DOE/NNSA Response to the 2011 Fukushima Incident. You can see more free data sets on the Data.Gov web site.

Since the set included latitude and longitude, I created a KML file. I have no idea exactly how dangerous those levels of radiation are, but it's still interesting to see what was found and where they sampled.

I love xtide, the Unix tide prediction server. I have it serving web pages and serving a telephone dial-in number in Asterisk for the beach I visit. I finally got around to writing the KML file that links placemarks to the URL for my copy of the Xtide web server. Click on the placemark to see the URL for the location's tide prediction page.

Also, you can now view KML files in Google Maps by typing in the URL to the KML file in the search bar. You'll end up with a URL in Google Maps that looks like this: http://www.google.com/maps?q=http%3A%2F%2Fcw.sampas.net%2Fkml%2Fxtide.kml&hl=en&ll=37.439974%2C-131.660156&spn=101.116429%2C158.027344&sll=37.0625%2C-95.677068&sspn=54.357317%2C79.013672&vpsrc=6&t=h&z=3&source=gplus-ogsb .

The xtide.kml file is in the usual place.

I used the same math from previous kml files to create a US master list of Military Training Routes. VFR routes are in green, and IFR routes are in red. Some segments overlap. Overall, they just look weird, so I'm wondering if its at all accurate. (Note: DO NOT USE FOR NAVIGATION.) Placemarks are waypoints that are along the route lines. Line descriptions contain route descriptions, while placemarks contain point lead-in and depart information. I don't think kml has a good way of displaying lines and points as the same object with different descriptions.... but what do I know about KML anyway?

See the KML and KMZ in the KML Archive. The sheer number of lines and placemarks may use up all your memory.

I have updated my KML output script so that the KML it outputs is valid, thanks to the KML Validator. The latest version of Google Earth is not nearly so tolerant of poorly written KML, which I only recently noticed when I tried to open my KML files that had worked just fine previously.

The main problems were my coordinate lists, where instead of delimiting by a space between tuples, I had delimited with a newline. I also did not close the coordinate sets with the first coordinate. The FAA doesn't either, because it's obvious. You draw a line from the last coordinate to the first. After the loop, I do a recordset.movefirst and write the first coordinate pair AGAIN.

Anyhow, you can see the new file in the KML archive. I may get around to doing more than just the SUA files. I'm also considering migrating the entire codebase to Python for portability. And because all the cool kids are writing in Python, and I can't stay in vbscript forever...

This KML file contains the FAA's special use types of airspace: alert areas, military operations areas, prohibited areas, restricted areas, and warning areas.

I have an updated AWOS KML file that will show you the telephone number, frequency, and AWOS type for the airports listed in the FAA's AWOS text file. You can download it here. As always, the KML archive is here.

This file uses the airport's latitute and longitude rather than the AWOS' latitude and longitude, which is missing in some cases in the FAA's file.

Also, the FAA files seem to have arbitrary layout changes from release to release, as well as some data quality issues. (Missing data, data out of alignment, etc.) I'm glad I don't have to produce this stuff on deadline.

After losing a disk, I finally got around to rebuilding the database and scripts to generate KML files from the FAA's NFDC subscription. First to be redone is the Special Use Airspace KML. Microsoft's SQL Server 2008 does a far better job of importing files than SQL 2005 did. The airspace KML archive is here.