I see Jacques van der Hout has just done a 28.71 Alpha 500 www.gps-speedsurfing.com/default.aspx?mnu=user&val=41905&uid=2814,
I gather his reach in was around 40kts and then getting to 33 on the way out on his CA 44.

Hot snot, that will fire up some of the boys
me I'd be happy with 23

thats smokin! 40 knots square reach is quick! wonder if his proximity is set at 50m?

The race to 30 knots is on!

What will go first; the 30 knot one hour, or the 30 knot alpha?

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AUS1111 said...

The race to 30 knots is on!

What will go first; the 30 knot one hour, or the 30 knot alpha?

Wow, what an interesting question, I've just had to check the GTC individual rankings. At the moment Sam Doecke has both of them with a 26.34 hr and a 27.95 alpha, so on that evidence it looks like the alpha could get there first.

A 30 knot alpha sounds possible (not by me). Although the potential for crashing into a gybe at 40knots is scary. A 30 knot hour would need so many planets in alignment and a great deal of skill.

It would be interesting to see Antoine, Bjorn, Finian etc. having a serious crack at these.

Man that is fast!!

I have had a look at his tracks and he is smokin' in both directions.
He sent me another just a few days ago where he thought he had cracked the 30 knots Alpha. He had!!! BUT, they didn't make the 50 proximity circle. I had to extend it to just over 60m to catch them.
When I emailed him this he said words to the effect:'no problem, I could have done that easy but I just didn't realize I had to...'

Holy Smoke! Get ready for the next session!

This one was not the fastest average but the fastest speed both ways. Sensational!!

Phenomenal!, I assume he had good conditions? Flat water, plenty of steady wind?

Interesting his minimum speeds, they're around where mine are, I was thinking I'd have to improve my min. speeds to get a really good alpha, looks like it's the peak speeds both ways that counts.

In response to some discussion with some of the guys at GPS-SS I have been looking over some of my recent data on Alphas again. Specifically I was comparing the Doppler results from the GT-11 and GT-31. I was surprised to find that with the latest firmware in both (GT-11 V1.62 B1115 and GT-31 V1.2 B1405x ) the results are very similar. This was not the case with earlier firmware where I saw some really bad deviations in the Doppler in the GT-11 and in the Trackpoints in the GT-31, and none of the results consistently came within a bull roar of each other.

My latest data suggests that with these firmwares the GT-11 and the GT-31 can be pretty well directly compared with Doppler quite reliably.

The differences I am seeing now are probably down to the position I wore the GPS on my body. The GT-31's I have been wearing in my helmet and the GT-11 I have been wearing on my arm so I can see it during the runs.

To confirm this I will run both in the helmet for a few sessions to see if this makes a difference and if the data is pretty much the same.

I would make the bold suggestion now, after reviewing the data I have, that we should be able to simplify and even up the matter for the Alpha by going all Doppler with the Navis. Just make sure you have the latest firmware listed above. The earlier GT-31 firmware is crap for Alphas.

If anyone else is able to run the same comparisons between GT-11 and GT-31 please let me know. The more data we have, the more confident we can be.

Yeah Decrepit, he is going so freaking fast on the straights it doesn't matter as much.
But I recon the min speed of 7.5 knots in the fastest one is a bit suss. Imagine how fast it may really have been!

AFAIK it is behind a low break wall in a boat harbor and is just about the right length for the Alphas and petty well square to the wind. Grevelingenmeer - Herkingen, Netherlands

Yes I wondered about the 7.5, I've never had a good alpha with the min as low as that, but then I don't go any where near those speeds. He must have a really good recovery and acceleration coming out of his gybes. If he's on a CA44 it must be fairly low in the water at 7.5kts

I think this is the spot:

Yep. Here it is in GE:

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decrepit said...

Yes I wondered about the 7.5, I've never had a good alpha with the min as low as that, but then I don't go any where near those speeds. He must have a really good recovery and acceleration coming out of his gybes. If he's on a CA44 it must be fairly low in the water at 7.5kts

yeah that 7.5 is very suss..the guy is listed as 90kg's (i know what the 44 is like at that speed and i'm 20kgs less) so hes pretty much stopped then got the 'mother of all sling shot like gusts' to catapult him back up to the miid 30's!...i would of been struggling to get my back foot locked in the strap.
these prove that a fast gybe is not all that necassary- for those results anyway...if he could pull min speed gybes of 15kn regulary or more he may be looking at more than 30 for the alpha.i counted 7 gybes on the weekend with mins of 14kn plus and 2 or 3 at 15 plus and i only just cracked a 25 (doppler) most missed the proximity.
the problem being low reaching speeds 27/28ish.

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snides8 said...


yeah that 7.5 is very suss..the guy is listed as 90kg's (i know what the 44 is like at that speed and i'm 20kgs less) so hes pretty much stopped then got the 'mother of all sling shot like gusts' to catapult him back up to the miid 30's!...i would of been struggling to get my back foot locked in the strap.
these prove that a fast gybe is not all that necassary- for those results anyway...if he could pull min speed gybes of 15kn regulary or more he may be looking at more than 30 for the alpha.i counted 7 gybes on the weekend with mins of 14kn plus and 2 or 3 at 15 plus and i only just cracked a 25 (doppler) most missed the proximity.
the problem being low reaching speeds 27/28ish.

Funny, I have the same problem!

Maybe there is a happy medium here between fast longer radius gybes or very tight radius slower gybes?
If Jacques had a 7kt min then he might of nearly wedged the tail in backwards - and then like snides says - goes slingshoting out into a fully G'd up reach..
There still appears to be a few different ways to approach the alpha.

I have very little doubt that the 7 knots min in that particular gybe is wrong as I said before. All Jacques other gybes have min speeds similar to mine and Snides and definitely above planing speed.

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sailquik said...

I have very little doubt that the 7 knots min in that particular gybe is wrong as I said before. All Jacques other gybes have min speeds similar to mine and Snides and definitely above planing speed.

Maybe the jetski had a fuel blockage.............oops did I just say that out aloud.

Actually what's even stranger is the 26.945 kn alpha with a min speed of 2.469kn. Don't tell me he's doing a jump gybe at 36 knots

here is a very good one from his last session. More normal min speed of 12.5 knots:

35 knots+ on a square reach is STINKING fast!!

This bloke must be BIG & STRONG!!!!

Sailquick,
is that a screen shot the guy sent you, or is it an analysis from your computer(have you got the file?) if it is from yours have you checked it in realspeed and/or pro?
i have found some discrepancys between results and the other 2 programs... maybe i havent got gpsresults set correct....
do you know how to set the proximity in results? i cant seem to find a setting..

cheers in advance
snides

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snides8 said...

Sailquick,
is that a screen shot the guy sent you, or is it an analysis from your computer(have you got the file?) if it is from yours have you checked it in realspeed and/or pro?
i have found some discrepancys between results and the other 2 programs... maybe i havent got gpsresults set correct....
do you know how to set the proximity in results? i cant seem to find a setting..

cheers in advance
snides

I have a couple of files from Jacque.
One of the discrepancies between GPS-R and RealSpeed is that for alphas, Manfred has implemented using the calculated trackposition from the Doppler data when using the Dopper speed info. Preliminary review suggests this lead to some errors in the proximity. Some Doppler calc'ed runs make the proximity but the trackpoint calcs say they miss. I think we will have to stick with the positional data for the Alphas when using the Doppler speed.

AFAIK there is no way for the user to adjust the proximity in GPS-R. It seems hard coded in.

There is also the different way that GPS-R can do the calcs. Rectangular, Trapezoidal, Cubic spline and quadratic integration. You can set these in the Extras-Filters menu, but for Alphas I think GPS-R is set to Rectangular and RealSpeed is set to Trapezoidal.
Discussion continues in the GPS-SS tech group about which methods to settle on.

i reckon you could have a good crack at these categories mate,

at burrum you laid down a 24+ knot alpha and a 22+ knot 1 hr, and the whole time waving as you went past the camera.

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sausage said...

sailquik said...

I have very little doubt that the 7 knots min in that particular gybe is wrong as I said before. All Jacques other gybes have min speeds similar to mine and Snides and definitely above planing speed.

Maybe the jetski had a fuel blockage.............oops did I just say that out aloud.

Actually what's even stranger is the 26.945 kn alpha with a min speed of 2.469kn. Don't tell me he's doing a jump gybe at 36 knots

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Gestalt said...

i reckon you could have a good crack at these categories mate,

at burrum you laid down a 24+ knot alpha and a 22+ knot 1 hr, and the whole time waving as you went past the camera.

sausage said...

sailquik said...

I have very little doubt that the 7 knots min in that particular gybe is wrong as I said before. All Jacques other gybes have min speeds similar to mine and Snides and definitely above planing speed.

Maybe the jetski had a fuel blockage.............oops did I just say that out aloud.

Actually what's even stranger is the 26.945 kn alpha with a min speed of 2.469kn. Don't tell me he's doing a jump gybe at 36 knots

Thanks Gestalt, but I think I've got a long way to go before pulling off 27+ alphas although I would love to have a proper crack at a 1 hour. I was surprised with Burrum result as I was going so far down the course that it was slow going punching back out wide up the course in the chop. I reckon if you stayed between the last marker and where the barge was moored you could stay relatively square and get the flat conditions to boot.

BTW- great to be back at work

Hi guys,

Good to see interest in our Dutch Alpha racers over here. Indeed it's the spot Jacques pointed out. It's a very low brick wall and with the predominant windderection from the SW I guess you may expect more. I've seen his runs myself during that day and I can tell you Jacques is right when he says it can be even faster over there.

The course is just perfect for Alpha with the straigh wall and superflat water on the way in. On the way back chop stays low as well.

Perhaps it's good to mention Jacques gave up what would undoubtfully have been a huge World Cup slalom carreer and he has won numerous legs in slalom against the very best of his time. He is super fast and knows how to gybe. I think indeed it won't be long before 30 will be broken by him.

Cheers,
Martin

So Martin why don't you Dutch guys get a team together and join the GPS Team Challenge
www.gpsteamchallenge.com.au/index.php?country=0

It's gone international now, and with the numbers you guys are getting you'll be very competitive.

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decrepit said...

So Martin why don't you Dutch guys get a team together and join the GPS Team Challenge
www.gpsteamchallenge.com.au/index.php?country=0

It's gone international now, and with the numbers you guys are getting you'll be very competitive.

We're certainly will push things and as soon as Dylan has got time he will also create the link you guys discussed in the e-mail exchange. Record rankings and other daily, monthly and yearly rankings come first. It's just a shame we have got such limited time. We could also advertise for your site, even if Dylan wouldn't have time for it, during our races which will start from May onward.

We will organize FSM (Fun Speed Meetings) this year and I feel many participants (mostly not the hard core racers) will feel very good about team challenges. During the FSM races we will also set up teams and it could be good to link results to your website. It would be good if you could send me a short presentation of the thought behind the site and I am for sure willing to advertise your site during this race. Also during our hard core USM races with over 100 people attending we could think of setting up teams. Lets give this a better though through e-mail. Please send comments to martin at gps-speedsurfing dot com and I will talk with Dylan and Roger about it.

Cheers,
Martin

Sorry Martin I must have given the wrong impression, it's not my site, it belongs to nebian.

The idea is for teams to post their gps results for 2sec, 5X10, 1hr, NM, alpha and distance. it needs at least 2 sailors to sail the same day, for the score to count.
We've been doing it in Aus since May 07 and it's been a great success, this year it went International and there are now teams from NZ, Croatia and Japan.
Any queries should be addressed to nebian, PM him from here, or hit the contact button on the GTC site.

OK Decrepit, I will do so. I fully agree it would be fun if the some Dutch crews would join the challenge. I am planning to make a presentation and make copies to hand out during the first skippersmeeting of our races (starting in May), and inform the people. Lets hope teams will be installed and participation will be high. Dylan is already in contact with Nebian. I will ask for the status and come up with additional questions and remarks to see if and how we can support.

On the subject of alphas here is one from Snake at Sbay. Pretty quick at 23.6 but an unusual approach. I would be interested to get some thoughts.



And here is my effort same place same day, a mere 23 (both trackpoints)



Also we have found quite big deviations even with latest firmware still on GT11 doppler vs Tpoint.
Here is the best doppler result. 24.16

Here is the best track point result 23.52



And the track point with proximity 53m that now shows the same track as doppler and a result of 24.84.



This is clearly different to the usual. I recently had a 23.74 doppler which gave a 23.91 trackpoint. As it was on a GT31 I used the doppler result.

I thought sailquick said that now the doppler results with the GT11 should be reliable?