I am under the overwhelming impression of the slalom sailors at PWA.
What do you think - GPS Speedsters -about competing against a pro in the business of the slalom racing?
1) Could you win easily against because there are rough water speedsters?
2) Do you gybe much better, because your alpha is flat water? If there is any comparison possible between the best in GPS Keiser like and AA skills at all?
The question is very practical.
If we do invite the best PWA sailors for our GPS competition like a Burrum Windfest 2020; you do expect to beat them easily ) because there are slalom riders
b) Antoine Albine will prove to be as competitive as you are at all 5 GPS categories (?)

I've sailed with a 50-knot speedster (Boro) and a PWA pro (Marco Lang) at my home spot. Unfortunately, not at the same time, and only Boro sailed the local speed strip. Both were way faster than anyone else sailing here the same day, but the difference in chop was larger for Marco. I think only the fastest speed sailors would have a chance of beating PWA pros, and then mostly because of experience in speed runs and faster gear. Beating them in alphas would be even harder; Taty Frans is on top of the alpha list for the US, and he got that spot in more chop and less wind than most others near the top (and he rarely ever posts sessions). Planing through a jibe in chop surrounded by lots of other guys at a mark is way harder than an alpha jibe on flat water.

The GPSTC disciplines where beating PWA guys would be easiest would be 1 hour and distance. They sail quite a bit on race days and training days, but usually with breaks every few minutes. Their big muscles might need those breaks .

Given equal skill levels, I think it would come down to rigging adaptability. It would depend how well each sailor could set up their gear for the other discipline and conditions. I've noticed that it takes a while for very good slalom sailors, who start speed sailing, to get into the go fast mode, down wind. They are used to tuning for best average speed over a course rather than peak down wind speed. And it's similar for me the other way round, I've only recently realised my lack of speed square is because I've tuned to go deep.

3.15 mark

Who is the fastest sailor in the world? Albeau in Luderitz. The PwA guys know how to go fast....

Br Alex

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cad184 said..
Who is the fastest sailor in the world? Albeau in Luderitz. The PwA guys know how to go fast....

Br Alex

Not surprising. Even if there was a PWA sailor out there who had never before seen flat water, they would be going very fast first attempt. Macro's question I thought was more directed at the converse. Are there very fast speed sailors out there, with terrific Alphas who have never seen rough water? How many hours TOW before they could even do a dry gybe?

Lets thing a second about a technique for fast alpha on flat water. We possibly want to make it as smooth as possible, trying to power all the time and convert every piece of wind into speed all the time. So not too much carving, not too much laydown. We have all the time guaranteed contact with the water. Slalom rider on rough water must be prepared on another hand to get a chop, fly a bit above, so need better grip to the water. Each one sailor is tuning their gybes TOW constantly. So please correct If I am wrong, but I do suspect that technique of slalom gybe will be a bit different to GPS alpha. If we could find a video of the one fastest ever gybe on Youtube we could bring here and compare to slalom gybe.Very unlikely that we can get GPS logs from PWA racing session, but I very doubt that those best sailors in the world do anywhere close to 27ktn mark alpha on their racing gybes.

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Macroscien said..
Lets thing a second about a technique for fast alpha on flat water. We possibly want to make it as smooth as possible, trying to power all the time and convert every piece of wind into speed all the time. So not too much carving, not too much laydown. We have all the time guaranteed contact with the water. >>>>

Depends if you're trying to make the 50m separation. A long smooth gybe may be the fastest, but it will also be wide, meaning slight up wind legs in and out. The best alpha can be a very tight gybe with slight downwind legs in and out. This means heavy carving, with maximum Gs. Min speed can be down to 15kts, but it's not there for long. Where as a longer smoother gybe may have min speed of 20kts but it's there for longer. I think there's no uniform best way, it's going to differ with the individual's skills, and equipment.

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cad184 said..
Who is the fastest sailor in the world? Albeau in Luderitz. The PwA guys know how to go fast....

Albeau obviously is fast, but his speeds in Luderitz are also a result of the most runs on the channel. He's been there a bunch of times; at least one time, he had his own truck & driver to drive him back to the starting line, so he did not have to wait. That enabled him to get about twice as many runs as the other guys. Experience on the channel seems to be quite important - most competitors improve their speeds when they come back, or if they are lucky enough to get multiple days with very good conditions.

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Macroscien said..
Lets thing a second about a technique for fast alpha on flat water. We possibly want to make it as smooth as possible, trying to power all the time and convert every piece of wind into speed all the time. So not too much carving, not too much laydown. We have all the time guaranteed contact with the water. Slalom rider on rough water must be prepared on another hand to get a chop, fly a bit above, so need better grip to the water. Each one sailor is tuning their gybes TOW constantly. So please correct If I am wrong, but I do suspect that technique of slalom gybe will be a bit different to GPS alpha. If we could find a video of the one fastest ever gybe on Youtube we could bring here and compare to slalom gybe.Very unlikely that we can get GPS logs from PWA racing session, but I very doubt that those best sailors in the world do anywhere close to 27ktn mark alpha on their racing gybes.

I think the technique for a good racing jibe and a good alpha jibe is quite similar, if not identical. Perhaps the biggest difference is that you have to bend your legs in typical slalom chop, while you can get away with straight legs on flat water. Or maybe it's the bad wind and the distraction from all those guys around you.

There's a few PWA guys to look at in the alpha rankings. Ben van der Steen holds the #2 spot with 30.3 knots; his top speed that day was 46.1 knots. Taty Frans "only" has a 26.16 knots alpha, but he did that with a comparably low top speed of 35.3 knots. It's pretty flat where he did his alpha in Bonaire, but not as flat as some of the best speed strips.

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boardsurfr said..

cad184 said..
Who is the fastest sailor in the world? Albeau in Luderitz. The PwA guys know how to go fast....

Albeau obviously is fast, but his speeds in Luderitz are also a result of the most runs on the channel. He's been there a bunch of times; at least one time, he had his own truck & driver to drive him back to the starting line, so he did not have to wait. That enabled him to get about twice as many runs as the other guys. Experience on the channel seems to be quite important - most competitors improve their speeds when they come back, or if they are lucky enough to get multiple days with very good conditions.

That may be explain why AA is the fastest here and there(speed and slalom) . I think that not many PWA slalom riders bother to travel to Lauderitz for pure speed.They may find that needle like board , have nothing to their everyday slalom, so waste of time.

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boardsurfr said..

I think the technique for a good racing jibe and a good alpha jibe i

Sadly I could not find good video tutorial or even written instruction for alpha 30kts for dummies. I imagine one day somebody could post as easy to follow the instruction that guarantees 30 ( if done exactly ) .
Something like that:
1.Conditions
a) wind 35 kts (?)
a) chop not higher then 10cm (?)
2.Equipment
a) board 80L (?)
b) sail 6.4 (?)
3/ Then details about gybe
a) what to do with sail ( when to flip, lay down or not etc )
b) footwork ( where to place feet and when, when to get into straps etc)
4) Don't ever drop the speed
a) below 15kts
b) below 20kts for more then 5s
c) below 30kts for 15sAgain, it could be nice to have access to GPS log with 30kts alpha, that we could analyze in GPS software.

Here's a couple of links to Stroppo's 28.69kt alpha
www.ka72.com/Search/r/5/m/stroppo/t/0/tf/2013-03-26

www.gpsteamchallenge.com.au/sailor_session/show?team=105&date=2013-03-26

It's an SBN file and all I have on this OS is Peter's Speedreader which won't open it. I'll have a look at it later when I'm not as busy.

But in the meantime I'll look at my own 26.4kt and get back

Sorry missed the speed numbers out. The bottom dashed line is 5kts, then the solid is 10, then 15 dashed, then 20 solid, 25 dashed, 30 solid, 35 dashed. The black circle is 50m radius. For my gybes you can change your 10cm chop to not much more than 10mm chop



OK I gave in here's Stroppo's from GPSResults.


So here the gybe looks a tad wider than 50m and min speed is similar, but runs in and out are faster. I think that's the secret, it's the legs that are important not so much min gybe speed.

So my 2 cents worth, to get a decent alpha you need to go for them in the same sort of conditions that could also provide a 2sec pb and therefore a lot of guys don't even bother trying when the conditions are good. Heading slightly upwind before the turn is hugely advantageous if you want to make the 50m radius and allows you to bear away to regain speed once you are on the return leg. A bit of luck is also needed to get the very best out of the conditions as there are points in the alpha that would be perfect for a big gust to hit you and other times I wouldn't be able to keep hold of the rig. I have a 27knt Alpha in the bag due to sailing in optimum conditions but I get beaten by fairly average sailors in a slalom race as I can't handle the chop.

Many slalom racers don't bother with GPS sailing, but when they do they are near the best, eg Brad Anderson, recently 3rd in the GI nats, also had world record 30kt hr and 47kt 2 sec

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decrepit said..
Here's a

Do you remember what was wind speed when you did your best alpha?If the excess wind could be actually prohibitive? With my skills when the wind really really on, I have a problem to depower, but that is me and possibly local conditions.I could see the guy finishing Lauderitz and forced to do extreme gybe at extreme speeds at the very end.What could be the speed at the end of the channels when sailors are hitting 50 kts? Can anybody initiate gybe when at 40 kts or it is too risky?

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decrepit said..
Here's a couple of links to Stroppo's 28.69kt alpha

That is absolutely fantastic day , speeds and alpha even nautical mile !!!

If that is position for the best alpha ?

That gybe sure looks good for an alpha, nice and tight and looks to be holding good speed, (at that angle, he must be pulling lots of Gs) And a true carve, the sail stays at right angles to the board, which does help to depower it through the gybe.

Lilacs's is a fantastic spot at it's best, from Stroppo's alpha to end of the NM can be very flat even at 25kts, if the weed and tide are right.

I only had a 35kt 2sec so I'm guessing the wind was around 25kts, but the water conditions where exceptional. Here's the GTC link.

www.gpsteamchallenge.com.au/sailor_session/show?date=2016-01-23&team=2

You can see by the tracks it's just across the channel from Strops session. which side is best depends on wind direction.

I've never managed 40kts, so don't know how I'd go gybing at those speeds, but that gybe at 33kts wasn't a problem as the water was so flat.

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decrepit said..
It's an SBN file and all I have on this OS is Peter's Speedreader which won't open it. I'll have a look at it later when I'm not as busy.

SBN support was added a couple of versions back, in 1.28. You should be able to open it Stroppos SBN file you have the current version. If not, send me the file and I'll check what's going on.

Never mind, I had missed the ka72 link. Stroppo's file has more than one clock rollback. I'll have to look at it in more detail.

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boardsurfr said..
SBN support was added a couple of versions back, in 1.28. You should be able to open it Stroppos SBN file you have the current version. If not, send me the file and I'll check what's going on.

Now you say it, I think I remember that.
But for some reason I've only put version 1.27 on the SSD, changing now.
That's better V1.29 up and running, thanks Peter, you've got to keep an eye on this silly old fart.

Funny thing in Stroppo's file: there's a -1 second adjustment early on, which is not unusual (leap second correction). But there's also a -1 day adjustment almost an hour into the session. That's pretty strange - why would the date be wrong for almost an hour? It's exactly a 1 day minus one second adjustment, so it's not from two sessions somehow ending up in the same file.

Here's a speed to beat: 589 knots doppler, 9849 knots trackpoint:

That was on the foil . The foil crashes are very good at producing artifacts (maybe because I have so many, or maybe because the waterstarting sometimes takes a long time). Interesting example where the doppler speed is loosely coupled to the trackpoint speed. This is from a Motion at 10 Hz. Artifacts on the GW-60 tend to be a lot smaller.

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boardsurfr said..
Funny thing in Stroppo's file: there's a -1 second adjustment early on, which is not unusual (leap second correction). But there's also a -1 day adjustment almost an hour into the session. That's pretty strange - why would the date be wrong for almost an hour? It's exactly a 1 day minus one second adjustment, so it's not from two sessions somehow ending up in the same file.

Seems like the whole GPS thing is a bit of a mystery, I don't see how it could be user induced, the time is set automatically. So that lets Strop off the hook.
Maybe it's only expecting errors in the seconds and doesn't check the day as regularly? But how did it get out in the first place? A stray cosmic ray perhaps.

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boardsurfr said..
Here's a speed to beat: 589 knots doppler, 9849 knots trackpoint:
That was on the foil . The foil crashes are very good at producing artifacts (maybe because I have so many, or maybe because the waterstarting sometimes takes a long time). Interesting example where the doppler speed is loosely coupled to the trackpoint speed. This is from a Motion at 10 Hz. Artifacts on the GW-60 tend to be a lot smaller.

So Yahn's not using an acceleration filter?

I only used GPSAR to show the data, since Speedreader does not show trackpoint speeds. GPSAR always had acceleration filters as an extra step, but it seems to give the correct 2 second top speed for the file with min. sats = 6; disabling the satellite filter gives a top speed of 56.75 knots. I bet Albeau had more than 3 satellites (totally ignoring that his speed was gate measured).