I was unable to resist a major purchase: a Garmin eTrex Venture HC hand-held GPS unit, which I thought would be fun to play with on my windsurf. It wasn't the first time I'd bought a GPS for windsurfing. Back in the day when I lived in Virginia I went through a couple of similar eTrex units. (They are not nearly as waterproof as advertised.) This time I'm keeping the thing in an Aquapac to be on the safe side.
Some of my motivation to get back into sailing with a GPS came from reading Peter Richterich's blog, "The Windsurf Loop." Peter is savvy about analyzing his speeds and tracks on the computer, using a program called "GPS Action Replay." Looking at the nerdy gloriousness of that program, I knew I had to try it. Today there was a good side-offshore breeze and the waves were very small, so I got my gadgets together to do a GPS-recorded speed session. I used a 106 liter freestyle-wave board and a 6.8 meter squared wavesail, which is not a particularly fast setup, but whatever. Here's a screenshot from the gspar program with an analysis of part of my track.
The program said my max speed was 23.4 knots (26.9 mph), which is a little lower than what the GPS itself said was my max speed (27.9 mph). I'm not sure why there's a discrepancy, but it might be that there are too few "bread crumbs" in the track file saved in the GPS and uploaded to the computer for analysis. I think I can change the GPS settings so it records at a higher frequency, and that might help.
Another cool stat that gspar can calculate is your minimum speed in jibes. My maximum minimum speed was 9.8 knots (11.3 mph). I'd say that's planing, but barely.
Heh. As if the GPS data logging wasn't obsessive enough, I also filmed the session with my GoPro camera and made it into the video below, set to a song by The Brother Kite.
No comments:
Post a Comment