Hello all,

Yesterday we had a quite windy (and super gusty) day here in Finland and some records were broken? I'll list here the data I have and also leave links to original files. You can then speculate if my calculations are correct.

I was on skis and had a LF Envy 2011 7m2 kite, wind was ~15-16m/s and gusts somewhere 25m/s. Data logger was a Ventus G730 and as a back up I had another logger also. I do realize that I don't own a GT31 logger so all results are more or less "valid".

First link includes filtered data from my gps, filtered means that I've taken off all accelerations over 4m/s2. Second link has been calculated with trapeze setting on and last with doppler setting. Software I used was GPSAR Pro:
http://toaster.fi/~Frk/KiteSpeed/24_3_2011_filtered.html
http://toaster.fi/~Frk/KiteSpeed/24_3_2011_filtered_trapeze.html
http://toaster.fi/~Frk/KiteSpeed/24_3_2011_filtered_doppler.html

As far as I've understood, my device doesn't support doppler and results are too (in)accurate in that sense? From KA72 I got results http://www.ka72.com/TrackRecalc.aspx?fid=13041 which are a bit different from GPSAR calculations but still in the same line.

Original files are at: http://toaster.fi/~Frk/KiteSpeed/data/
24_3_2011.gpx file is exported from gps logger via GPSBabel and those others starting with W are from Nokia Sportstracker (+external bt gps receiver). That Sportstracker data is filtered already
in software so it's not that accurate and there no doppler support at all. There are multiple files because I have to shut down logging if wan't to see max speeds during session.

Here's also a short clip from a one "show off" http://www.youtube.com/watch?v=Pp3GKisvABc

So, how fast can we go?

-Pete

After I removed all speed values from gpx-file and uploaded it to ka72 (so calculations are made based on trackpoints, not doppler), following results came up:http://www.ka72.com/TrackRecalc.aspx?fid=13050

65.5 knots = 75,37 mph = 121,3 km/h are the ~same as in other calculations.

Comments?

edit: mph was wrong

That is exceptionally fast. Can you tell us about the experience? Do you have lots of time doing speed sailing?

Well, not so much to add...I waited that kind of conditions over two years and then all parts came together. Ice was smooth but still there was enough grip and wind came off-shore so it was super gusty. Speed it self didn't feel so fast, meaning that going faster is possible. All the time I had full control of the kite. Mainly I do speed kiting only when the conditions are correct, normally just freeriding. I'd like to kite more but job is cutting a bit too much quality time