Mar 31 2009
the need for (GPS logged) speed…
Last weekend I was out in Colorado, for some quality time on snow in the mountains (which I haven’t been seeing much of lately).
My friend John and I headed up to Winter Park for a few days. I had brought along my GPS data logger (a BGT-31, used to measure windsurfing speed records), so I could log our runs. The snow was warm, firm, and fairly fast, and we entertained ourselves seeing how fast we could go. The max speed recorded on the GPS increased throughout the day, and on the final run the GPS registered a speed of over 50 mph. John was undoubtedly going faster with his downhill gear, but I was on my teles and had the ‘official’ recording device.
After we retired back in our gasthaus at the end of the day, I downloaded the track log from the GPS device and converted them into KML for viewing in Google Earth (via gpsbabel and some python scripts). I was surprised to see that the top speed recorded was actually 61.8 mph. My (untested) theory is that the difference was because the max speed reported was the horizontal velocity, while the KML placemarks descriptions show the 3-D velocity.
Here are some KML files of the tracks:
- 2009-03-20-morning-runs.kmz
- 2009-03-20-afternoon-runs.kmz
- 2009-03-21-morning-runs.kmz
- 2009-03-21_afternoon_runs.kmz
On the third day we headed up to Berthoud Pass for a bit of backcountry skiing. It was a nice sunny day with little wind, but the snow was a bit rotten due to the recent warm spell. John, on his retro skinny randonee setup, ended up taking a abrasive faceplant on the descent due to the funky snow conditions. Load up the following file and navigate to 2009-03-22T18:05:27Z to see the exact location.