Fast but not that fast on a foil

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powersloshin said..
Waterbouy,
just to explain there has been a long running issue in the gps community about non approved devices giving unreliable spikes. For speed the first requirement is to use 2 sec. average instead of max speed, that usually takes out about .3/.6 of a knot. Also approved devices record the precision of each fix, at least once a second, latest devices as much as 10 times a second, so any files can be analized for anomalies.
At the moment the most stringent requirements are enforced by GPS Team challenge: www.gpsteamchallenge.com.au/
If you are interested and are prepared to get an approved device you can join one of the teams, our Botany team is the Double Demerits, best foilers are Berowne, Dieter and Julian. I can lend you a device if you want to come for a try.
On KA72 it is possible to post with any devices, and there is a 'Windfoilers worldwide' group with monthly standing , but some foilers feel that because any device is allowed the results are not so reliable, so they did not join: ka72.com/

I believe that even for allowing for spikes you could be the fastest in NSW, so it would be worthwhile for you to join the gps team challenge. I joined many years ago and made a lot of friends, but I am slow so did not hurt any egos

Hey powersloshin, thanks for the info. Firstly I don't want to sound like an ass but I'm not into the whole dick swinging comp about who's the fastest and all that goes with it. I'm happy to sit on the fringes doing my thing and work out what makes a sailboat/ sailboard or foil go faster.
'I've spent the last 41 years racing all types of sailing craft be it dinghies, skiffs, sportsboats, keelboats and Multi''s . Windsurfing and now foiling is my on water down time to send it and just go nuts! Like my windfoiling I sit on the fringe and occasionally read Seabreeze to see where the benchmark is at, seldom do I comment for the very reason the way this thread has gone...
I've been around the windsurfing scene long enough to see the first version of the "RAF" sail which was actually a plywood fully battened moth sail cut down to suit a windsurfer rig. Anyway enough said and time to climb back under my rock. Oh and I do agree with the GPS spike thing, I wear two gps units (one on the underside of each wrist) so I can track and watch trim adjustments in real time. Interestingly enough it seems when it feels fast and out of control it's slow and just when you think you ain't going fast the numbers are good. Between the two units it's east to see the numbers.

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powersloshin said..
I bet everyone is furiously wet sanding their foils now...

It does make a huge difference, the sail gp teams go to 5000 grit although they alter the finish to suit water temp and salinity..

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waterbouy101 said..

powersloshin said..
Waterbouy,
just to explain there has been a long running issue in the gps community about non approved devices giving unreliable spikes. For speed the first requirement is to use 2 sec. average instead of max speed, that usually takes out about .3/.6 of a knot. Also approved devices record the precision of each fix, at least once a second, latest devices as much as 10 times a second, so any files can be analized for anomalies.
At the moment the most stringent requirements are enforced by GPS Team challenge: www.gpsteamchallenge.com.au/
If you are interested and are prepared to get an approved device you can join one of the teams, our Botany team is the Double Demerits, best foilers are Berowne, Dieter and Julian. I can lend you a device if you want to come for a try.
On KA72 it is possible to post with any devices, and there is a 'Windfoilers worldwide' group with monthly standing , but some foilers feel that because any device is allowed the results are not so reliable, so they did not join: ka72.com/

I believe that even for allowing for spikes you could be the fastest in NSW, so it would be worthwhile for you to join the gps team challenge. I joined many years ago and made a lot of friends, but I am slow so did not hurt any egos

Hey powersloshin, thanks for the info. Firstly I don't want to sound like an ass but I'm not into the whole dick swinging comp about who's the fastest and all that goes with it. I'm happy to sit on the fringes doing my thing and work out what makes a sailboat/ sailboard or foil go faster.
'I've spent the last 41 years racing all types of sailing craft be it dinghies, skiffs, sportsboats, keelboats and Multi''s . Windsurfing and now foiling is my on water down time to send it and just go nuts! Like my windfoiling I sit on the fringe and occasionally read Seabreeze to see where the benchmark is at, seldom do I comment for the very reason the way this thread has gone...
I've been around the windsurfing scene long enough to see the first version of the "RAF" sail which was actually a plywood fully battened moth sail cut down to suit a windsurfer rig. Anyway enough said and time to climb back under my rock. Oh and I do agree with the GPS spike thing, I wear two gps units (one on the underside of each wrist) so I can track and watch trim adjustments in real time. Interestingly enough it seems when it feels fast and out of control it's slow and just when you think you ain't going fast the numbers are good. Between the two units it's east to see the numbers.

Waterbouy101, 40 posts on these forums, a self-professed, lifetime of windsurfing but yet still seemingly unaware of the GPSTC protocols?Really? Not into dick swinging? You seem quite happy to claim/post numbers that are near world-record levels before doing due diligence.

I'm aware of unapproved Garmin/Suunto watches showing max speed 5 knots higher than 2 sec on approved devices.

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DarrylG said..
How about we forget about peak speed and all just quote 500m speeds. Helps to Gets rid of effects of a spikes.
Being able to hold a speed is more impressive than a freek peak.

My Suunto Ambit 3 watch displays 10sec average speeds.
If my peak speed is within 1 knot of the 10 sec I'm confident it's not a spike.
Accurate enough for freeride foiling, downloads tracks and has lasted close to 1,000 sessions

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DarrylG said..
How about we forget about peak speed and all just quote 500m speeds. Helps to Gets rid of effects of a spikes.
Being able to hold a speed is more impressive than a freek peak.

Not rewarding for my catapults.

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Steve Charles said..
So it does seem that getting over 26 is a bit of stumbling block. I know these guys have gone faster but its interesting.

KA72 WINDFOILING
Rider2secFichierLieuDateDarryl31.08Majestic Point08/06/2021
AUS20026.66Rosetta10/06/2021
Boston26.6Valentine04/06/2021
jusavina26.5Manly04/06/2021
Dieter26.5Kyeemagh08/06/2021jpqr26.3Baie de Sainte-Marie03/06/2021
TonyK26.12The Train10/06/2021
AUS154Chris23.61The Train10/06/2021
Swindy22.1Dawesville08/06/2021
Andrew Haigh20.35Coal Point09/06/2021
stroppo20.29Point Walter08/06/2021
powersloshin17.49Kyeemagh08/06/2021

It's our idle speed on a quick warm up lap ,in preparation for our big 30 run

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Steve Charles said..
So it does seem that getting over 26 is a bit of stumbling block. I know these guys have gone faster but its interesting.

KA72 WINDFOILING
Rider2secFichierLieuDateDarryl31.08Majestic Point08/06/2021
AUS20026.66Rosetta10/06/2021
Boston26.6Valentine04/06/2021
jusavina26.5Manly04/06/2021
Dieter26.5Kyeemagh08/06/2021jpqr26.3Baie de Sainte-Marie03/06/2021
TonyK26.12The Train10/06/2021
AUS154Chris23.61The Train10/06/2021
Swindy22.1Dawesville08/06/2021
Andrew Haigh20.35Coal Point09/06/2021
stroppo20.29Point Walter08/06/2021
powersloshin17.49Kyeemagh08/06/2021

Just search KA72 and filter for over 30 knots.
This is a screenshot of this year. Obviously there are a few results that shouldn't be there ( driving home etc) but you can see the wall is more like 30 / 31 knots. Similar if you look at GPSSpeedsurfing site.

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DarrylG said..

Steve Charles said..
So it does seem that getting over 26 is a bit of stumbling block. I know these guys have gone faster but its interesting.

KA72 WINDFOILING
Rider2secFichierLieuDateDarryl31.08Majestic Point08/06/2021
AUS20026.66Rosetta10/06/2021
Boston26.6Valentine04/06/2021
jusavina26.5Manly04/06/2021
Dieter26.5Kyeemagh08/06/2021jpqr26.3Baie de Sainte-Marie03/06/2021
TonyK26.12The Train10/06/2021
AUS154Chris23.61The Train10/06/2021
Swindy22.1Dawesville08/06/2021
Andrew Haigh20.35Coal Point09/06/2021
stroppo20.29Point Walter08/06/2021
powersloshin17.49Kyeemagh08/06/2021

Just search KA72 and filter for over 30 knots.
This is a screenshot of this year. Obviously there are a few results that shouldn't be there ( driving home etc) but you can see the wall is more like 30 / 31 knots. Similar if you look at GPSSpeedsurfing site.

I wish my wall was 30/31

As I'm probably the last foiler in WA not to do 30kn and have also hit the wall at 26. I figured stability over 25kn is my biggest issue at my skill level. My go to foil in windy conditions is the supercruiser with a 1300 front wing which is so much fun but I do like to scare myself occasionally on the GTR. I got a NP F4 flight evo some months ago but only used it a couple of times and didn't have the small wing for it until recently.
I know it's been done before so I decided to add 200mm to the fuse in the tail section in the hope this may help. Never having done this kind of thing before it was a bit nerve wracking putting a hacksaw through a perfectly good foil. It's been a big learning curve but seems to have turned out OK.
I had a quick go on it this week but was underpowered . The few flights I got it felt really good but need to tweak mast foot position a bit next time. Main thing is it didn't break. It's now 99cm from front to back of wings which is 9cm more than the GTR. The tail section is now 2.5mm bigger all round than original so its fairly rigid. Time now to grow some and get it out for a proper test in the next few days hopefully.

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Steve Charles said..
So it does seem that getting over 26 is a bit of stumbling block. I know these guys have gone faster but its interesting.

KA72 WINDFOILING
Rider2secFichierLieuDateDarryl31.08Majestic Point08/06/2021
AUS20026.66Rosetta10/06/2021
Boston26.6Valentine04/06/2021
jusavina26.5Manly04/06/2021
Dieter26.5Kyeemagh08/06/2021jpqr26.3Baie de Sainte-Marie03/06/2021
TonyK26.12The Train10/06/2021
AUS154Chris23.61The Train10/06/2021
Swindy22.1Dawesville08/06/2021
Andrew Haigh20.35Coal Point09/06/2021
stroppo20.29Point Walter08/06/2021
powersloshin17.49Kyeemagh08/06/2021

I would agree that I still hit the wall around 26ish

What the hey?
You guys aren't seriously trying to go fast on those huge foils are you?
Anything over 900 sq cm is mainly for course slalom.
To hit any decent speed, you need to use foils from 400 sq cm to maybe 650 for the biggest riders.
If it foils up at 18 knot boatspeeds it will top right out by 28.

Its an I65 cover so if it doesn't go fast at least it will carve well in swells.

So you agree, small foils for speed.

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PhilUK said..
On my laptop I use GPS-Results software which has a filter, the same as the main GPS-Speedsurfing website which gets rid of irregularities. Uncheck the filter box and you can see the difference.

You know that the unfiltered data are 4 knots too high, but you believe that the filtered data are accurate? That's very optimistic. Filters at the default settings only remove the worst artifacts.

The top speed you show is 7 knots faster than the previous second, and the next second is 5 knots slower. Such acceleration/deceleration does not even happen on a windsurf board. On a foil, the actual speed differences from second to second are typically much lower, and a 5 knot deceleration without a crash is pretty much inconceivable. Basically, the per-point error of the watch is in the range of several knots - about 10-fold higher than what the units approved for the GPS Team Challenge show. With such poor quality data, even 10-second runs will have a typical error somewhere around 1 knot - which is worse than typical single-point max errors for a Motion or similar high-accuracy unit.