Speed over the earth’s surface ?
“No matter where you go, there you are.”
-Buckaroo Banzai
…checking your videos
I can see other guy in a longboard or funboard that rides equal or faster
so, how do you explain that?
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I would urge you to calibrate your measurements. Try running with the device on. See how fast it says you can run 100 meters and whether that is twice as fast as Carl Lewis’ best.
Been there, done that Blakstah . . . we have two gps units ,both give similar results, both are functioning correctly
Ever seen a ferrari cruising in the supermarket parking lot ?
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Yo T.B.
I’ve got a Lambrogini, Mazerrati, & a Ferrari. They’re all have been appointed with strings, bells and whistles just for you to pull! Go for it mate!
I love your videos. Whenever I need to sit back and chill I can depend on you. Keep up the beautifull progressive composite woodworking.
You are truely in a class by yourself.
Meet you at “Warp~Speed” on that wave we share to see whose running faster, Rich
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We have already ( long ago) established that the maximum speed on a wave is related to the the maximum speed of the wave.
And what is the relationship ?
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e.g. you cant surf 100 mph on a 10 MPH wave.
But one can do 35 on a 10 mph wave !
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Modern surfing is not a " LINEAR ( straight line) speed" - focused sport,(Like swimming ).
Modern surfing is past its use by date 
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BUT (since the 70’s) we have needed to “cut-back” to catch up to the the wave, so the board is now faster than the wave.
And since the 70’s there have been waves which are too fast to make, so the board has also been slower than the wave
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So whats the big hype about speed, and in what direction and for what duration ?
The hype? . . . Speedialer, speeedfins, etc etc etc. . . that’s the hype, the reality is that having the ability to create more speed means that one can make more sections and more waves
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If you were going 15 mph on a board and ran from the tail to the nose at 5 miles an hour would you be going 20 miles per hour???
No because when you run forwards what you are doing is pushing the board backwards, slowing it down
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Speed IN THE WATER gets my vote because speed over earth is the waves speed but speed in the water is the boards speed irrespective of your progress over land. (Like the Teahpoo comment from DougSchuz post #20)
Unless your spending an innordinate amount of time in the air…
What period of time are these speeds held for ?
An instant at 50 or 60 KPH means what again???
Or are these speeds being held for useful lengths of time where the surfer is clearly seen by all (on land and water) to be shooting off into the stratosphere?
I’m with the lazy anchovie on this one Doug.
S.
Tom, I have a nagging question, and I ask it because I really don’t know, but I’m curious:
How does a GPS measure speed? I thought they were only for establishing location: Global Positioning System.
Doug
yes…and as you move from one point to another, you have traveled over distance “D” in time “T”. speed = D/T
Soulstice, Makes sense. So if that’s the way Tom is doing it…
The GPS device triangulates off any four of 12 available satelites in each hemisphere. It tells its own position to within 10 feet, plus or minus. So Tom has to have the GPS with him on the board, he needs two locations on the fly, and a stopwatch to record the time needed to travel between the two points. Since there is a slight lag time for the location to register on the device, and there is a slop factor of 10 feet in all directions, how can the calculation be accurate?
Tom, I am respectfully fascinated by the actual details of how this works. I must be missing something. Can you fill in the blanks?
Thanks, Doug
a log type device seems to me to be the only truly accurate way to measure speed over water
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Speed IN THE WATER gets my vote because speed over earth is the waves speed but speed in the water is the boards speed irrespective of your progress over land.
Quote:Actually Spuuut, according to Terry Hendricks and Bill Barnfield, who have used GPS units and impeller based speed recorders simultaneously, the results from both kinds of unit agree closely (as one would expect). . . this is probably because these days GPS units measure speed three dimensionally (i.e they measure the downwards speed during the drop as well) </blockquote></div>What period of time are these speeds held for ?
That depends upon the setting. . .
however what you have to understand is that the recording interval does not make a great deal of difference to the recorded peak speed ( at least between 1/10th of a second throught to say, 1 or 2 seconds)
This is because the surfer has a relatively slow rate of acceleration (always less than the rate of free fall in a vacuum) and it thus takes several seconds to accelerate to a top speed of say 30 mph. . . . you can’t just instantly accelerate to 30 mph for a tenth of a second , it takes time to get there, so if one has reached 30 mph one has necessarily acheived a sustained burst of acceleration lasting several seconds… . . .
. . . . . thus although a slightly higher reading will be achieved with a very short interval, a short interval does not change the fact that a sustained burst of acceleration is needed to get there. . . . . and this means that the readings prior and close to the peak speed will also be close to the peak speed.
Do you understand what I am saying ?
Quote:An instant at 50 or 60 KPH means what again???
See the answer above. . . .a 60 kph reading means that a sustained burst of acceleration lasting several seconds has occurred. . . . . an ‘instant’ of speed cannot happen in isolation because of the limited acceleration available to the board and rider
Quote:Or are these speeds being held for useful lengths of time where the surfer is clearly seen by all (on land and water) to be shooting off into the stratosphere?
Of course these speeds are being ‘held’ for useful lengths of time. . . whether or not this is seen by all is another matter .
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a log type device seems to me to be the only truly accurate way to measure speed over water
Not true silly, gps units and impeller based units achieve very similar results.
You can’t make the fact that my boards are exceptionally fast just ‘go away’ by niggling about gps units. . . they work !
I also notice that when other people post gps speeds ( thinking of a recent 3rd hand report posted here, of 35 mph achieved in San Diego )we get comments like “congratulations!. . the bar has been raised again” . . … . and not a murmur of complaint about using GPS. … . . in my opinion the unfounded criticisms about gps units which only seem to be posted when I go fast are just a desperate attempt to avoid the apparently painful truth that my boards are much faster than those produced by all the respected industry icons and legends of the world combined !!
I suggest that some of you take your heads out of the sand and realise that I am producing state of the art speed boards, sorry about the haircut, that’s just the way it is !!
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Speed over the earth’s surface ?
No, speed measured three dimensionally in space, using the surface of the earth as a reference grid
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Surfer magazine had an article a few years ago about some watchw ith gps in it that they used to measure the speed of a wave rider in a typical beach break, I forget the times. But Tom, I think you are going to need to get unaltered video evidence with a neutral swaylockian present before people will accept your claims. Hell, I still have to prove bigfoot exist, and alien, and chupacabra, and the lochness monster, and the Yeti.
Might as well come out with it and call me a liar, why beat around the bush ?
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Roy, why not just cross-verify with a radar reading or 6 and put the boys’ minds at ease?
greg