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Vendee Globe 2012


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#1401 Damers

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Posted 27 November 2012 - 03:38 PM

Estar, very interesting stuff. If I read it correctly you are using Gouph as a mark for the routing exercise, understand. But what if you took it out and re-run the models with the Aiguilles as the only mark. Sure JPD (and FG) will probably run south of Gouph but what does it give for ALC? Is he able to run down the ridge between the two highs?

#1402 steinbrenner

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Posted 27 November 2012 - 04:05 PM

Sure JPD (and FG) will probably run south of Gouph but what does it give for ALC? Is he able to run down the ridge between the two highs?


gough to starboard, somebody said earlier

but i agree that's not fully correct to calculate with gough as a mark because it's allowed to pass anywhere north of gough (of course if gough to stb is mandatory)

#1403 Fishing boat

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Posted 27 November 2012 - 04:21 PM

JPD and Gabart are going to be GONE when they hit the southerlies turning to westerlies. Gabart actually did a nice job of bailing out and taking his short term losses to JPD. That is a hard thing to do. Routing should be due south right now. Ignore Gough and the Gate. Ignore the results and the distance to the mark. ALC and AT have fallen into the St Helena trap. My guess is that they don't get out of there for a long time! AT should get out now and take his lumps. My educated guess. Fascinating to watch from the couch!!!!

#1404 popo

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Posted 27 November 2012 - 04:22 PM



hey AT, don't you want to protest ? It's supposed to be singlehanded isn't it ?



this guy seems absolutly crazy ! He probably sniffed too much Sikaflex in his sail locker !

#1405 Foolish

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Posted 27 November 2012 - 05:06 PM

I'm all for the progress in singlehanded boats, but geez, these guys are clean shaven. Can't we even show that this is a wilderness adventure by coming back with a thick beard full of crumbs.

#1406 Kenny Dumas

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Posted 27 November 2012 - 05:07 PM

If the high really stays that far south, maybe ALC can stay North of the whole mess and beat into it at ~28 degrees S, straight for the cape. I don't know if it's ever been done, but this might be the one time it works. Looks like AT may follow him also. Evans, any chance you can run the router on that option? (and thanks for your great posts!)

#1407 Estar

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Posted 27 November 2012 - 05:48 PM

guys, I looked at the option to stay north and keep going for the ice gate. I showed a route that did that yesterday. That was clearly what BP was counting on. But the forecast now has shut that door. The ridge persists too long and BP would be going to slow, and then the high pressure sets up right in the way and would stop it dead. He now has to go close to G island.

Below is the routing to the ice gate without considering G island. As you can see it goes just south of G island. This is for 12/4 and you can see the high pressure right in the way of the northern route (and that there is more wind toward the S and W)

BP's direct/shortest route was always a risk. Its only very rarely been successful in these RTW races. But for a while the picture was so muddled that no-one knew what the correct path was and a reasonable approach was just to bag as much distance to the mark as possible. We all just have to give JPD great credit for seeing the new picture first and committing to it.

We are dealing here with the extreme edge (And beyond) of the forecast accuracy window. So the forecast is very likily to change (you can almost count on it). BP can hope that the more direct path reopens. But I doubt it, as the trend has been to a worse ridge and a worse high.

Attached File  1204.jpg   328.29K   174 downloads

#1408 TheDragon

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Posted 27 November 2012 - 06:59 PM

If the high extends any further south it will prevent them all from leaving Gough Island to starboard! We will have boats pinching up just to make Gough Island before diving back south, then up again for the ice gate. Rather inelegant, but I suppose better than ice roulette.

#1409 r.finn

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Posted 27 November 2012 - 07:49 PM

Agreed EStar. If BP's decision to stay north works it will be the move of the race, but he put an awful lot on the line in breaking his cover. It's the kind of move that only Nicolas Troussel gets away with. Hopefully some of that rubbed off.

Virbac and Macif are in a reliably good possition. They will be the first to enter the South's "don't break the boat" competition. Great race so far. I hate that Riou hit a channel marker in the middle of the ocean though. Ridiculous that such a thing would find him out there.

#1410 ronnie_simpson

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Posted 27 November 2012 - 08:30 PM

Estar, you are killing it! Thank you!

#1411 Terrafirma

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Posted 27 November 2012 - 08:46 PM

It seems to me Jean Piere Dick's westward gamble is backfiring. Clearly he doesn't think he can match the other leaders which is a surprise to me. The boats East have made better speed and course to the gate while JPD sails off the race.

#1412 Trickypig

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Posted 27 November 2012 - 08:48 PM

guys, I looked at the option to stay north and keep going for the ice gate. I showed a route that did that yesterday. That was clearly what BP was counting on. But the forecast now has shut that door. The ridge persists too long and BP would be going to slow, and then the high pressure sets up right in the way and would stop it dead. He now has to go close to G island.

Below is the routing to the ice gate without considering G island. As you can see it goes just south of G island. This is for 12/4 and you can see the high pressure right in the way of the northern route (and that there is more wind toward the S and W)

BP's direct/shortest route was always a risk. Its only very rarely been successful in these RTW races. But for a while the picture was so muddled that no-one knew what the correct path was and a reasonable approach was just to bag as much distance to the mark as possible. We all just have to give JPD great credit for seeing the new picture first and committing to it.

We are dealing here with the extreme edge (And beyond) of the forecast accuracy window. So the forecast is very likily to change (you can almost count on it). BP can hope that the more direct path reopens. But I doubt it, as the trend has been to a worse ridge and a worse high.

Attached File  1204.jpg   328.29K   174 downloads


Your plotted chart shows it all.The big question is how many hours the more southern boats have at 20+ knots of boat speed before the front finally reaches BP?

The ice gate may well be a `starting gate'.

#1413 Trickypig

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Posted 27 November 2012 - 08:49 PM

It seems to me Jean Piere Dick's westward gamble is backfiring. Clearly he doesn't think he can match the other leaders which is a surprise to me. The boats East have made better speed and course to the gate while JPD sails off the race.


Wait until the front hits and they arc up. Although since they have to turn left and make G Island it may have the effect of them bringing the breeze back to him but not overtaking.

#1414 jhc

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Posted 27 November 2012 - 08:50 PM

This race is taking a page from the early Whitbreads. A two thousand mile beat to S.A.? The combination of the southern position of the anticyclone, and the northern position of the ice-gate, viola, a split fleet, the leader intent on sailing to windward, against the southeast trades, while second thru 13? have no choice but to take a southern route, and then north, around the ice-gate.

#1415 popo

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Posted 27 November 2012 - 09:13 PM

I'm not surprised by JP Dick's move to try to find stronger winds, he is one of the best heavy wind sailor of the fleet (remember that he is one of the only one able to keep it with the master himself, the professor, the great the only Mich Dej ! during BWR and last Vendee)

#1416 popo

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Posted 27 November 2012 - 10:12 PM



watching this, I can't help wondering.
Are they turning mad being alone on their boat ?

#1417 Estar

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Posted 27 November 2012 - 10:50 PM

There is some hope for BP yet!

A souther ocean low pushes up a crush zone/trough which gets him out of the ridge and into some wind earlier than the prior forecast. Good drag race for all three boats, but with the wind much further forward for BP than the other two.
Attached File  1130.jpg   181.39K   109 downloads

Then the high creates a real challange right over the track - no wind in the center, not much room between the center and the G island starboard mark, and slow head winds above. How to handle it will depend on exactly where the center goes. VBP & M will hope it goes a bit further north and gives a narrow track of wind just north of G island. BP will hope it stays south and blocks off the southern route.

Attached File  1202.jpg   143.79K   113 downloads

Right now, with this routing, VBP & M arrive at the ice gate within minutes of each other and BP is 4 hours later. But remember I am using the same polar for all (which is probably a little slower than these boats). SO in reality its a three way tie right now.

#1418 Trickypig

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Posted 27 November 2012 - 10:51 PM

This race is taking a page from the early Whitbreads. A two thousand mile beat to S.A.? The combination of the southern position of the anticyclone, and the northern position of the ice-gate, viola, a split fleet, the leader intent on sailing to windward, against the southeast trades, while second thru 13? have no choice but to take a southern route, and then north, around the ice-gate.


Gough Island is at 40 deg S and with this low I think it'll be some hard downwind sailing in the next week.

#1419 Fishing boat

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Posted 27 November 2012 - 11:03 PM

Someone needs to come up with a betting pool on these things. The intrigue is fantastic. I would bet the farm (and the house and the cars and the kids and all of life's great pleasures) on Macif and JPD. BP is toast to the east!

#1420 Trickypig

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Posted 27 November 2012 - 11:15 PM

There is some hope for BP yet!

A souther ocean low pushes up a crush zone/trough which gets him out of the ridge and into some wind earlier than the prior forecast. Good drag race for all three boats, but with the wind much further forward for BP than the other two.
Attached File  1130.jpg   181.39K   109 downloads

Then the high creates a real challange right over the track - no wind in the center, not much room between the center and the G island starboard mark, and slow head winds above. How to handle it will depend on exactly where the center goes. VBP & M will hope it goes a bit further north and gives a narrow track of wind just north of G island. BP will hope it stays south and blocks off the southern route.

Attached File  1202.jpg   143.79K   113 downloads

Right now, with this routing, VBP & M arrive at the ice gate within minutes of each other and BP is 4 hours later. But remember I am using the same polar for all (which is probably a little slower than these boats). SO in reality its a three way tie right now.


Estar, I'm not sure what the timing of your weather charts are. Does that second chart show the high that follows the low they are hunting? Is there a date on that forecast?

If it is, I think they'll get to Gough Island before it. ie I caculate on Google Earth that JPD has less than 1100nm to Gough Island and although they're flapping around now there's a good chance they'll speed up and be there by Friday.

My money is on Macif 1st to Gough.

#1421 Estar

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Posted 28 November 2012 - 12:07 AM

Estar, I'm not sure what the timing of your weather charts are. Does that second chart show the high that follows the low they are hunting? Is there a date on that forecast?

Sorry, managed to cut the dates off those, but they are in the jpg names - The first is 11/30 and the second is 12/02. So, yes the high follows.

If it is, I think they'll get to Gough Island before it. ie I caculate on Google Earth that JPD has less than 1100nm to Gough Island and although they're flapping around now there's a good chance they'll speed up and be there by Friday.


My route for JPD has him sailing 1167nm, at an average speed of 9.5kts = 5 days. My polars do seem a bit slow for these boats (which in this situation may mostly benefit BP, if he is much faster in the light stuff than my polar). But remember, the high rotates counterclockwise, so if they get there earlier, they get head winds (S/SE), which will then slow them down. And the center might still roll over them. So, in that routing they do get to the mark first but then essentially stop (under 5kts of boat speed) for 10 hrs.

My personal favorate is JPD. I liked him before the race, and so far in the race he was patient until he saw an opportunity (And he was the first to see it) and then he jumped on it and executed. I also think his experience will prove useful in the stronger downwind stuff. But right now I think its a toss up, and mostly depends on weather factors that we cannot accurately predict so far in the future.



#1422 Estar

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Posted 28 November 2012 - 12:21 AM

just looking at the tracker ...it has JPD going only 1.5kts. hope he is ok, just stuck in a hole, and has not lost a mast.

#1423 ronnie_simpson

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Posted 28 November 2012 - 12:23 AM

he was doing 0.8 a couple hours ago.... also hoping for the best as well. hope it's just a tracker error!!!

#1424 Trickypig

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Posted 28 November 2012 - 02:01 AM

My take is that a nw-sw - s. breeze will get them to the gate . As you say 9.5knots is conservative and as they make their southing I think 12 -15 knots will more likely.

#1425 Slim

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Posted 28 November 2012 - 03:25 AM

AT breaks it down.



#1426 popo

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Posted 28 November 2012 - 08:10 AM

This is on ! JP Dick is starting to touch the wind and Armel is dead stuck ! 11knts vs 3.7
Le Cam's position seems very very good too !

#1427 bombarie

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Posted 28 November 2012 - 08:12 AM

This race is taking a page from the early Whitbreads. A two thousand mile beat to S.A.? The combination of the southern position of the anticyclone, and the northern position of the ice-gate, viola, a split fleet, the leader intent on sailing to windward, against the southeast trades, while second thru 13? have no choice but to take a southern route, and then north, around the ice-gate.


Yeah real interesting to see BP trying to cut across the Helena High --- from the last 3 Volvo's at least we have learned that to reach Capetown fastest, you dip as deep South as you dare on the Western side of the Atlantic, and then ride the lows East to basically south of Capetown, and only then come back up (in the last Volvo it wasn't that extreem, I think I recall in the one before some of the boats hit Capetown heading pretty much North). Not sure if all of those had icegates though.

Interesting to follow, now let's hope all remainders stay afloat and in competition and we have another brilliant 60 days to go.

#1428 Carboninit

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Posted 28 November 2012 - 08:52 AM

Someone needs to come up with a betting pool on these things. The intrigue is fantastic. I would bet the farm (and the house and the cars and the kids and all of life's great pleasures) on Macif and JPD. BP is toast to the east!


West is best ,The boats to the west pick it up first and go over the top of the boats to the east. Always go to the breeze and that's what Macif and others have done . Spot on , Game on.

#1429 Trickypig

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Posted 28 November 2012 - 09:04 AM

This is on ! JP Dick is starting to touch the wind and Armel is dead stuck ! 11knts vs 3.7
Le Cam's position seems very very good too !


... and even more breeze filling in for JPD, Francois G and J le Cam (the old dog).

#1430 Estar

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Posted 28 November 2012 - 12:13 PM

As predicted, significant fleet compression occured last night, with the 2nd pack to the west sailing up the new wind.

11/28: We now have a front row of 5 boats basically in line (BP, HB, CP, M, VBP - east to west). Western end well in the breeze while eastern end still sticky. (yellow track = BP, red=CP, purple=VBP)

Attached File  1128.jpg   126.63K   105 downloads

11/29: Breeze fills across the whole front line. Strong running for the western end.
Attached File  1129.jpg   124.44K   122 downloads

11/30: The back of the trough comes to the western boats with wind shifting (SW) to the beam, still with good pressure.
Attached File  1130.jpg   124.77K   97 downloads

12/01: High pressure starting to effect and slow western boats, while still some pressure on the eastern end. Western boats lose A LOT of time here.
Attached File  1201.jpg   122.52K   86 downloads

12/02: Western boats escape out below the high, while eastern boat (BP) may or may not have wind (gribs 5-10kts - very unreliable)
Attached File  1202.jpg   121.86K   91 downloads

12/04: All boats below the high in decent breeze.
Attached File  1204.jpg   124.18K   75 downloads

Looking forward its all about how well boats come thru the high pressure system. In this forecast the boats at the eastern end (BP) and at the western end (VBP) come in first and second, with the middle of the line slower. . . . but that will all depend on how the high plays out.

#1431 popo

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Posted 28 November 2012 - 12:30 PM



you really gotta stop doing this dude !



I don't know how you say "pétole" in english, (when there is no wind at all) so I translated it by "flat wind"

Thanks a lot Estar, it's easier to understand with you !
So it's sure that the western boats will be trapped in the light, but we can't no for sure if it's going to be as light for the eastern boat, is that right ?

#1432 steinbrenner

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Posted 28 November 2012 - 12:58 PM

jpd has a chair in the cockpit?!?! didn't notice it before

#1433 Estar

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Posted 28 November 2012 - 01:38 PM

So it's sure that the western boats will be trapped in the light, but we can't no for sure if it's going to be as light for the eastern boat, is that right ?


Everyone now has a definitive strategy and they (the 5 in the front row) are all posible winners. It's left now to who has the boat speed and some luck with the high pressure.

If the western boats are really really fast the next couple days, and the tongue of the high does not stick out east so far/so quickly, then they might slip by in front and escape below it. Right now they look like they will get in front of it, but it is then not sure if they will escape below into the favorable winds, before it rolls over them. If they manage that they will crush the course, because it is fast for them from there to the ice gate. Trickypig thinks they will manage the escape, and things have been trending toward that.

The question for BP is just how fast is he in 10-12kt winds from all directions. He should definitely manage to get in front of the high and sail a shorter course but he ends up with less favorable wind direction and less average pressure. Normally I would strongly bet against this routing, but the high pressure moving across the course 'may' block the western guys (or at least make them sail extra distance) and make it work.

Right now all we can say is it looks like it is going to be a close thing - I have BP getting to the ice gate 03:46 on dec 7th, VBP +4hours at 07:38, and CP +10 hours at 13:40. But any of that could easily change by 12hrs because the grib files are not very accurate when they say 5-10kts. As you saw in the JPD viedo sometimes when they say that its just zero wind, and sometimes its a decent 12kts of breeze.

#1434 Philippe_Chaplin

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Posted 28 November 2012 - 02:21 PM

PRB has arrived in Salvador da Bahia (as per the AIS track on Marinetraffic) where they will repair before to decide how to get the boat back to France,

#1435 STYACHT

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Posted 28 November 2012 - 03:16 PM

PRB has arrived in Salvador da Bahia (as per the AIS track on Marinetraffic) where they will repair before to decide how to get the boat back to France,

They should hang tight in Brazil for a month or so and then join the fleet in the Atlantic when they get around. Training against the best partners and a spectator boat second to none.

#1436 LeoV

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Posted 28 November 2012 - 03:54 PM

popo, petole, can be; dead calm.
Or if you mean that special area and want to be more nautical, do a search on horse latitude.

#1437 Speng

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Posted 28 November 2012 - 04:09 PM

Tactics!! Yeah baby. I reckon JPD is actually in the lead. LeCleac'h is too far east and his 100 mile lead relative to Gough Island is probably not enough to get him there first with the forecast he has. JPD is in a MACIF/Le Cam sandwich right now and the wind channel the forecast is predicting will have them sailing a deep direct course to the mark so it should be VMG sailing so the premium is going to be on boat speed and handling for the next couple days. Then it should be a light air reach over to the ice gate i think.

Anybody know what the betting houses have for odds on the race?

#1438 jrenedo

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Posted 28 November 2012 - 04:22 PM

we have just received this video from Bubi , he speaks about the next hours, while surfing at 21 knots ..





#1439 Estar

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Posted 28 November 2012 - 04:32 PM

I was just given a different (much faster) polar for these boats. It would mean that the front runners will all be able to beat the coming high, and the only question is how fast they can get into the breeze now. This faster polar has the western boats advantaged, as they are already in breeze and don't have to go as far south to duck the high. But still all very close +-4hrs to the ice gate. This polar seems faster than I would expect - it might reflect the designers intentions but we will have to see which one more accurately reflects the single handed real world. The boats seems to be more on the routing suggested by the slower polar I was previously using.

Attached File  1128.jpg   134.38K   95 downloads

#1440 MR.CLEAN

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Posted 28 November 2012 - 05:42 PM

Thanks Jesus! Send our best wishes to him. We'll wait 'til he gets to the big South before we ask for a live interview!

#1441 Trickypig

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Posted 28 November 2012 - 05:42 PM

Tactics!! Yeah baby. I reckon JPD is actually in the lead. LeCleac'h is too far east and his 100 mile lead relative to Gough Island is probably not enough to get him there first with the forecast he has. JPD is in a MACIF/Le Cam sandwich right now and the wind channel the forecast is predicting will have them sailing a deep direct course to the mark so it should be VMG sailing so the premium is going to be on boat speed and handling for the next couple days. Then it should be a light air reach over to the ice gate i think.

Anybody know what the betting houses have for odds on the race?


+1

#1442 MR.CLEAN

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Posted 28 November 2012 - 05:42 PM

Evans and popo thank you guys a ton. You're both making this MUCH easier and more enjoyable to follow.

#1443 Trickypig

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Posted 28 November 2012 - 06:06 PM

I was just given a different (much faster) polar for these boats. It would mean that the front runners will all be able to beat the coming high, and the only question is how fast they can get into the breeze now. This faster polar has the western boats advantaged, as they are already in breeze and don't have to go as far south to duck the high. But still all very close +-4hrs to the ice gate. This polar seems faster than I would expect - it might reflect the designers intentions but we will have to see which one more accurately reflects the single handed real world. The boats seems to be more on the routing suggested by the slower polar I was previously using.

Attached File  1128.jpg   134.38K   95 downloads


Estar, they would be quite a unique set of polars for the Open 60s. Do you have them for an actual Open 60?

Are the courses plotted on each respective chart a plot of the best course to sail for that particular synopsis with the same starting point?

#1444 jrenedo

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Posted 28 November 2012 - 06:44 PM

Thanks Jesus! Send our best wishes to him. We'll wait 'til he gets to the big South before we ask for a live interview!


I will !
cheers

#1445 Presuming Ed

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Posted 28 November 2012 - 06:50 PM

popo, petole, can be; dead calm.

I've always called it a flat calm.

#1446 Estar

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Posted 28 November 2012 - 07:09 PM

Estar, they would be quite a unique set of polars for the Open 60s. Do you have them for an actual Open 60?

The slower polar I was using was created by some French virtual sailors observing IMOCA60 actual single-handed racing performance. The faster polar comes from one of the current boat's designers, but he 'made it generic' to scrub out proprietary performance information. I personally think the actual performance this race seems somewhere in-between. If I have time, after this leg I will have enough data to adjust the polar to being a pretty good description (and much better than I have right now) of the front runners, but I will still not be able to differentiate between the boats or skippers.

My focus is more on understanding and explaining the weather features and their impact on the race, rather than in predicting the race performance of individual boats. I just want to be able to look forward in time at roughly the right place down the course to see what weather is there - so a 'generic' polar is good enough, but it does need to have the boat speeds reasonably accurate relative to the speed of the systems. Right now I think my 'slow polar' may be 20 or 30% slow, and the 'fast' may be correct for peak speeds on short courses with crew but too fast by 30 or 40% for singled handed RTW.

Are the courses plotted on each respective chart a plot of the best course to sail for that particular synopsis with the same starting point?

If I understand your question, yes (edit: except of course the optimized course for each boat starts at a different starting point)

I am using a standard routing program using the standard 'optimized isochrones' method.



#1447 Left Hook

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Posted 28 November 2012 - 07:49 PM

popo, petole, can be; dead calm.

I've always called it a flat calm.


Piss on a plate!

#1448 Estar

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Posted 28 November 2012 - 08:41 PM

OK, (after some back and forth with one of the designers in my bad french) I have adjusted the new ('fast') polar - it should be close now.

For those who want to know - we have a range of wind speeds across the fleet so I have matched the current boats speeds across the fleet with their current wind speeds and made the polar fit that as accurately as possible without changing the shape of the curves. That makes for 80% of my 'fast' designer's polar. The new average speeds along these routes are BP: 14.6kts, CP:15.8kts, and VBP:17.9kts.

At that speed the boats will be clearly in front of the high pressure, and it's basically going to be a drag race all the way from now to the ice gate.

Of the three I am tracking that still favors the two ends of the line: putting VBP into the ice gate first, BP in second (+8hrs) and CP third (+10 hrs).

However, while this routing says BP should be going quite southerly to get to the stronger winds asap - BP is currently steering a more easterly course (he's doing 150 and the routing says 165 degrees). So, his polar/routing must say that he is still better going further east even if it is in lighter wind. So BP may still have another card to play.

12/02 picture where you can see them well in front of the high.
Attached File  1201.jpg   171.14K   118 downloads

#1449 Trickypig

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Posted 28 November 2012 - 09:11 PM

Estar, thanks for such a thorough analysis. Nice to have an open 60 designer involved too!

#1450 HASYB

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Posted 28 November 2012 - 09:23 PM

Thanks Evans, very interesting!

#1451 Presuming Ed

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Posted 28 November 2012 - 09:29 PM


popo, petole, can be; dead calm.

I've always called it a flat calm.


Piss on a plate!


Harry Flatters

#1452 STYACHT

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Posted 28 November 2012 - 09:46 PM

Estar, really great to do the homework on the polars, and to refine the routing. Really you are doing for the Vendee more or less what Stan Honey and his well paid team did for course racing. Thanks for all the hard work.

#1453 popo

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Posted 28 November 2012 - 09:47 PM

a few questions for you Estar.
-What is your routing software ? Is there only one ? If not, do they have the same ?
-Does the routing software takes acount of the waves ?
-Can you set a percentage of speed ? for exemple if the skipper is too tired to go full on, or if the boat is crippled, like you don't have your gennaker anymore, can you set your polars to be without it ?
-When running a course, can you have "and if" set, like for Armel, for exemple, if he sets a "and if I can't achieve the theoretical speed, what happends to my routing in 1 day, 2 days, ...
-Last but not least, can you/do you wan tot/are you allowed to tell us who you are working for ?

thanks !

#1454 MR.CLEAN

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Posted 28 November 2012 - 09:49 PM

Buy a book in appreciation. I liked this one. http://www.bethandev...ue_horizons.htm

:)

#1455 popo

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Posted 28 November 2012 - 10:48 PM



first one from De Broc, If I understood well, he was having trouble with communication before.



quite sure that wasn't salad that he plowed !



I bet he is the only one still having bread on board ! If that doesn't make him a hippy !




sad



haaaaa sailing video !

#1456 Trickypig

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Posted 29 November 2012 - 12:01 AM

My guess... looks like the low is slipping south and the west group won't be getting their 30 knot+ winds, 15-25 knots maybe. If the weak front passes over them before friday they'll have a better angle into the island though.

#1457 Estar

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Posted 29 November 2012 - 01:11 AM

a few questions for you Estar.
-What is your routing software ? Is there only one ? If not, do they have the same ?

There are two main commercial packages: Expedition and Adrena. Maxsea used to be a player but has not kept up. There are couple good but less featured free programs, like QtVlm

-Does the routing software takes acount of the waves ?

They can, but I am not. One thing to be careful of is that because the weather data is not so accurate, it does not make so much sense to use a lot of time super fine tuning the other stuff (for weather routing, it does make sense to have really accurate polars for other purposes) because it will just get lost in the weather chaos.

-Can you set a percentage of speed ? for exemple if the skipper is too tired to go full on, or if the boat is crippled, like you don't have your gennaker anymore, can you set your polars to be without it ?

Yes, thats all easy in all the packages.

-When running a course, can you have "and if" set, like for Armel, for exemple, if he sets a "and if I can't achieve the theoretical speed, what happends to my routing in 1 day, 2 days, ...

Some things like that are available in the two pro packages, but a lot of scenario analysis you still have to do manually. I would guess that tools for scenario analysis will become a more developed feature in future releases.

-Last but not least, can you/do you wan tot/are you allowed to tell us who you are working for ?

Just a fan at the moment, doing this for fun and education. But in the past I have been 'owners rep' on a couple builds and rebuilds and know some of the French and Italian players as a result.

thanks !



#1458 Estar

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Posted 29 November 2012 - 01:45 AM

My guess... looks like the low is slipping south and the west group won't be getting their 30 knot+ winds, 15-25 knots maybe. If the weak front passes over them before friday they'll have a better angle into the island though.


Agreed

For the latest gfs gribs (note: I presume the racers are getting meto france gribs rather than gfs) and a bit old positions now . . .

for JPD from now all the way to the ice gate: (I would think just about exactly how he would like it . . . we can see how it changes)
10 -15kts= 2%
15-20kts=28%
20-25kts=49%
+25kts = 21%

For BP:
10-15kts: 29%
15-20kts:38%
20-25kts:37%
+25kts: 3%

#1459 rocket21981

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Posted 29 November 2012 - 03:07 AM

Just wanted to add to the chorus of huge thanks to popo and Estar for their efforts. Much appreciated.

#1460 us7070

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Posted 29 November 2012 - 03:21 AM

Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390

#1461 us7070

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Posted 29 November 2012 - 03:23 AM

It would be great if the position reports could be made available in the Expedition "Sched" format.

#1462 Trickypig

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Posted 29 November 2012 - 04:17 AM

Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390


Yes your routing and polars are the best bet; but I like the idea that with just over 600 miles to go to Gough Island and the front looming, there is only computer modelling and no weather stations to place it on the chart mid ocean, so maybe there's a chance it'll come sooner and everyone gets a crack at the lead.

#1463 alni

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Posted 29 November 2012 - 04:52 AM

Just adding our thanks to Popo and Estar, makes it that much more real.

#1464 onimod

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Posted 29 November 2012 - 07:37 AM

There is no actual requirement to go anywhere near Gouph Island is there - it just has to be to stbd?

#1465 Large Thomas

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Posted 29 November 2012 - 08:58 AM

There is no actual requirement to go anywhere near Gouph Island is there - it just has to be to stbd?


True. In the virtual Vendée Globe there's a whole pack of players sailing closely by the African coast. And as you have to be north of the first gate at least for a bit that in itself makes for no additional problem.

#1466 Damers

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Posted 29 November 2012 - 10:30 AM

Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390


Great work everyone, thanks.

Re: the Bluewater polars. I assume from Estar's comments that these are potential rather than likely when shorthanded (especially for long durations). With the performance drop off occurring at about 30kts for anything forward of 150deg I have two questions for you shorthanded and designer guys out there.

Does the realistic performance drop off occur earlier because you are reducing sail plan earlier or is it more because you don't have enough hands to constantly steer, trim, peel, reef, eat, sleep, etc.?

What are these guys actually looking for? Max wind compared to the others or nice, steady 20-25kts? Or, do they get to the point where (subject to extremes) wind angle is more important than strength?

Thanks.

#1467 Rhyddid

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Posted 29 November 2012 - 11:24 AM

For those interested AT live link up answering questions posted to his FB page..... @ 1230GMT (Nov 29th) on .http://www.alexthomsonracing.com/

#1468 mario147

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Posted 29 November 2012 - 12:02 PM

Estar, thanks for your excellent posts. At first sight.. what do you think about the followers, is it possible Bubi's pack can pass before the high closes the gate?

#1469 popo

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Posted 29 November 2012 - 12:18 PM



is this hair even real ?It has to be a wig !



seems like a PR requested video, but with Le Roi Jean, it turns funny !



Put this fucking mic next to your fucking mouth ! Subtitling is already hard enough, If I can't hear, it just turns impossible !
Bertrand seems quite stressed and disapointed, surely due to his dalayed start


Estar, thanks for your excellent posts. At first sight.. what do you think about the followers, is it possible Bubi's pack can pass before the high closes the gate?


At today's vacation, Bertrand DeBroc said that he thinks Bubi can make it, but not him

#1470 klymen

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Posted 29 November 2012 - 12:37 PM

Estar, thanks for your excellent posts. At first sight.. what do you think about the followers, is it possible Bubi's pack can pass before the high closes the gate?


I second the thanks to Estar - makes following the race so much more interesting. I'd also like to know what the outlook is for Bubi and the 'chasing pack'. They've been quietly making up lots of miles in the last few days but will they be able to bank them?

#1471 Estar

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Posted 29 November 2012 - 01:24 PM

We still have a front row of five boats, but as expected the middle of the line has sagged back a little and the back markers to the west have closed.

The finish order at the icegate right now (based on position only, remember I am using the same polar for all) is:

#1 VBP
#2 M +4hrs
#3 BP +7hrs (much slower average speed, but less distance sailed)
#4 SC +8hrs (The king hunts down the brits!!!!, highest average speed)
#5 CP +10hrs
#6 HB +13hrs
#7 G +15hrs

11/29: BP still in lightish winds, everyone else in decent breeeze
Attached File  1129.jpg   152.04K   39 downloads

11/29 midnight: BP finally gets the breeze and accelerates. You can also see (as Trickypig suggested) that the fleet misses the highest +30kt winds (yellow area).
Attached File  1130.jpg   157.26K   42 downloads

11/30pm: Wind shift to SW on back of the trough just starting to hit western end of fleet
Attached File  1130p.jpg   149.95K   42 downloads

12/01: all boats in the SW wind
Attached File  1201.jpg   153.99K   41 downloads

Average speed along these routes:
VBP: 18.1kts (distance sailed 1577nm)
M: 17.4kts
BP: 15.1kts (distance sailed 1428nm)
SC 18.6kts

VBP's wind distribution along his route:
10-15kts: 8%
15-20kts:30%
20-25kts:32%
25-30kts:30%

#1472 Speng

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Posted 29 November 2012 - 03:07 PM

the chasing pack is doing quite well. It'll be interesting to see whether Bubi can make a move. He should catch up a bit as he's bringing the wind with him and he seems to have the boat at full chat. Arnaud is making a move as well but he might be a bit too far west to avoid the softer winds after the shift. BdB and TdL are more likely a bit too far behind.

One thing i don't understand about the course shown on the VG tracker is the orthodromic route they show implies that Gough Island is to be left to port rather than starboard. It's a bit of a pain for looking at the tracker... What's the rule about the gates? Do they just have to touch the gate line or cross is from a specific direction or what?

Looking forward the top 8 should all be in the south in the same system as MG said which will require them to push in the Indian Ocean (fun for us but not for them <_< ) but the Kerguelen ice gate (I think) screws things up a bit as it may very make it necessary to go between the Kerguelens and Heard Island which isn't necessarily what you'd prefer as the shallow water there can make for bad seas. Also having two gates (Aigulles and Kerguelen) so close together restricts the course a bit much IMHO.

#1473 loguivic

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Posted 29 November 2012 - 03:24 PM



you really gotta stop doing this dude !



I don't know how you say "pétole" in english, (when there is no wind at all) so I translated it by "flat wind"

Thanks a lot Estar, it's easier to understand with you !
So it's sure that the western boats will be trapped in the light, but we can't no for sure if it's going to be as light for the eastern boat, is that right ?


I would say..."fart wind" nope?

#1474 aquila

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Posted 29 November 2012 - 04:46 PM

thanks again to popo and estar,
If only the sailors would start filming themselves doing a tack/gybe or a sail change I understand it might be too long for the lower budget campaign but for the leaders it should be affordable and it would make great viewing, and shouldn't entail much more that a well placed gopro or whatever they're using. anyone else agree?

#1475 Speng

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Posted 29 November 2012 - 05:47 PM

arguments against that:
(1) seems like some of them are using handhelds.
(2) tacks and gybes contain confidential or proprietary steps that the teams don't want to reveal
(3) Would you want someone filming you at work?
(4) a lot of the interesting stuff is invisible (ballast tanks, canting keel) or un-interesting to most non-sailors (stacking)

I think there are some vids out there of this done during training that you can find

#1476 jrenedo

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Posted 29 November 2012 - 05:59 PM

Some of them are probably filming those maneuvers but:
-it makes a long clip, that need some editing/cutting
-they are too busy or haven't got enough skills for that
-it would be very very expensive and power consuming to send the whole file
-most probably will be edited after the race , or sometime later in the race if they have a break (difficult but not imposible)

For example Bubi sent this one yesterday after climbing the mast 10 days ago , but he didnt have the time to edit it before..



#1477 Slim

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Posted 29 November 2012 - 06:34 PM

One thing i don't understand about the course shown on the VG tracker is the orthodromic route they show implies that Gough Island is to be left to port rather than starboard. It's a bit of a pain for looking at the tracker... What's the rule about the gates? Do they just have to touch the gate line or cross is from a specific direction or what?

From the VG website -

An Ice Gate is a segment on a given latitude, defined between two longitudes. The space between the longitudes is around 400 miles, the equivalent of one and a half day of sailing. There are four to six, or sometimes seven gates along the route and they are spaced out between 800 and 2,000 miles. In order to validate their crossing, skippers only need to sail through the gate from north to south, from south to north, or just keeping sailing north.

More.

#1478 Presuming Ed

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Posted 29 November 2012 - 07:10 PM

Liked this from Sam's fb page.

Déjeuner avec un de mes partenaires aujourd'hui - un qui a un sens d'humour: pate de lapin suivi par jambon sauce Madère ;-)



#1479 Willy Clark

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Posted 29 November 2012 - 07:34 PM

Go Javier!

http://clarksail.com...ng-for-acciona/

#1480 clwgr

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Posted 29 November 2012 - 07:35 PM

Just wanted to add to the chorus of huge thanks to popo and Estar for their efforts. Much appreciated.

+1

#1481 Trickypig

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Posted 29 November 2012 - 08:03 PM

We still have a front row of five boats, but as expected the middle of the line has sagged back a little and the back markers to the west have closed.

The finish order at the icegate right now (based on position only, remember I am using the same polar for all) is:

#1 VBP
#2 M +4hrs
#3 BP +7hrs (much slower average speed, but less distance sailed)
#4 SC +8hrs (The king hunts down the brits!!!!, highest average speed)
#5 CP +10hrs
#6 HB +13hrs
#7 G +15hrs.


Funny you should mention the polars.. As much as I would like to see le Cam/SC beat Stamm/CP to the ice gate, it looks as though Stamm/CP will be in good breeze shortly and his amazing boat speed should prevail. I think le Cleac/BP is going to struggle as he has to sail deeper angles to meet the pressure.

The Vendee tracker shows the front arriving in the next 24 hours but Passageweather.com shows it arriving later.

I found a website for a South African research station there and saw their weather observation page but unfortunately the last observations were in 2010. http://www.sanap.ac....ugh_weather.php

#1482 popo

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Posted 29 November 2012 - 08:50 PM

Dick is on fire ! More than 20 knots !
With the flat water he should have, this must be awesome and "easy" !

You're welcome all for your thanks, you'll have to wait a little bit for today's videos, I've been trapped by a bottle tonight !

Le Cleac'h was speaking this morning about the differences there is between UE and US gribs files.
Did you tried both Estar ?

#1483 Polar_William

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Posted 29 November 2012 - 09:03 PM


Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390


Yes your routing and polars are the best bet; but I like the idea that with just over 600 miles to go to Gough Island and the front looming, there is only computer modelling and no weather stations to place it on the chart mid ocean, so maybe there's a chance it'll come sooner and everyone gets a crack at the lead.


Indeed, weather models lack surface data / weather balloon sounding data over the big oceans. However, don't forget that a massive amount of satellite observations are included (surface winds, vertical humidity profiles and a lot more) which allows to localise fronts. So, models are less accurate than on the NH, but definitely do better than providing `model weather'. That ended for the southern oceans around 1979.

#1484 Speng

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Posted 29 November 2012 - 09:06 PM


One thing i don't understand about the course shown on the VG tracker is the orthodromic route they show implies that Gough Island is to be left to port rather than starboard. It's a bit of a pain for looking at the tracker... What's the rule about the gates? Do they just have to touch the gate line or cross is from a specific direction or what?

From the VG website -

An Ice Gate is a segment on a given latitude, defined between two longitudes. The space between the longitudes is around 400 miles, the equivalent of one and a half day of sailing. There are four to six, or sometimes seven gates along the route and they are spaced out between 800 and 2,000 miles. In order to validate their crossing, skippers only need to sail through the gate from north to south, from south to north, or just keeping sailing north.

More.


Must be something lost in translation; I understand "sail through the gate from north to south, from south to north" but not sure what "or just keeping sailing north" means. Does it mean keep completely north of the gate?

#1485 Trickypig

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Posted 29 November 2012 - 09:20 PM



Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390


Yes your routing and polars are the best bet; but I like the idea that with just over 600 miles to go to Gough Island and the front looming, there is only computer modelling and no weather stations to place it on the chart mid ocean, so maybe there's a chance it'll come sooner and everyone gets a crack at the lead.


Indeed, weather models lack surface data / weather balloon sounding data over the big oceans. However, don't forget that a massive amount of satellite observations are included (surface winds, vertical humidity profiles and a lot more) which allows to localise fronts. So, models are less accurate than on the NH, but definitely do better than providing `model weather'. That ended for the southern oceans around 1979.


I've been looking over Estar's routing charts, the tracker on the website, Passageweather.com and they don't always agree on where the centre of a low is or where the front is moving. Sometimes it looks to be up to 150 miles. I do know to check the time and date of each chart so to me it seems to show a certain inaccuracy.

#1486 Dog

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Posted 29 November 2012 - 09:36 PM



One thing i don't understand about the course shown on the VG tracker is the orthodromic route they show implies that Gough Island is to be left to port rather than starboard. It's a bit of a pain for looking at the tracker... What's the rule about the gates? Do they just have to touch the gate line or cross is from a specific direction or what?

From the VG website -

An Ice Gate is a segment on a given latitude, defined between two longitudes. The space between the longitudes is around 400 miles, the equivalent of one and a half day of sailing. There are four to six, or sometimes seven gates along the route and they are spaced out between 800 and 2,000 miles. In order to validate their crossing, skippers only need to sail through the gate from north to south, from south to north, or just keeping sailing north.

More.


Must be something lost in translation; I understand "sail through the gate from north to south, from south to north" but not sure what "or just keeping sailing north" means. Does it mean keep completely north of the gate?

I believe it means that a competitor can sail over top of the gate without actually passing through it since the intent is simply to keep the fleet from getting too far south.

#1487 DtM

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Posted 29 November 2012 - 09:45 PM

Must be something lost in translation; I understand "sail through the gate from north to south, from south to north" but not sure what "or just keeping sailing north" means. Does it mean keep completely north of the gate?
[/quote

Your interpretation is correct. if you want to simply sail completely north of the gate that is OK aas well.

As I understand it they must be north of the gate at some point to have observed the rule.

Interesting that Australian authorities have insisted on gates to keep the boats close enough to enable easier rescue and to avoid the Tony Bullimore type situation where the baots are at or past the limit of ASMA and the Navy to get to them in time.

#1488 Estar

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Posted 29 November 2012 - 11:55 PM

Only major change from this AM is that the routings for the western boats are driving deeper south after G ISland, in order to stay in the breeze and avoid a ridge extending out east from the high.

11/29 BP is still waiting for the stronger breeze. Should come in middle of the night.
Attached File  1129.jpg   140.79K   39 downloads

11/30 Back of trough arrives for western boats
Attached File  1130.jpg   140.61K   51 downloads

12/02 Western boats dive south to avoid patch of lighter winds - these lighter winds to the north cost BP 3hrs in this run (vs. this morning)
Attached File  1202.jpg   138.87K   52 downloads

12/03 Western boats come back north as wind fills in
Attached File  1203.jpg   136.28K   48 downloads

Regarding weather models - I am using GFS. We used GFS the couple times we have been in the southern ocean and it is ok - not perfect but none of them are. I am guessing the boats are primarily using the European model - which is not as easy for me to get in grib format. Our experience is that when you are looking out 5+ days you can only use the gross features (the stronger more persistent systems) because the finer features and the exact timing will almost certainly be wrong.

#1489 mad4it

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Posted 30 November 2012 - 12:16 AM

People seem to have forgotten Golding, he isn't known as the 'king of the south' for no reason! High daily averages and damage to the newer boats should see him and his play mate LeCam move up fairly dramatically, awesome to see Alex doing well though! Estar thanks for all of the routings very interesting!

#1490 tamaozy

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Posted 30 November 2012 - 12:29 AM

I reckon the Puma boys told them all about the great hospitality on Tristan so they are having a mandatory stopover, anchor in the harbour, swim to shore, go to the local pub, try a meal and three beers before swimming back to your boat and resuming the race. I like it.

#1491 DtM

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Posted 30 November 2012 - 12:45 AM

The meal will have to come below high water where they will wait up to their ankles or they will be DQ'd !!!!

#1492 Rail Meat

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Posted 30 November 2012 - 12:48 AM


Expedition routing is very close to that of virtual wind posted above by Estar.

it does seem to have the boats I routed staying ahead of the front.

I used the polars from here:

http://daysailer.wor...60-2/#more-2390


Great work everyone, thanks.

Re: the Bluewater polars. I assume from Estar's comments that these are potential rather than likely when shorthanded (especially for long durations). With the performance drop off occurring at about 30kts for anything forward of 150deg I have two questions for you shorthanded and designer guys out there.

Does the realistic performance drop off occur earlier because you are reducing sail plan earlier or is it more because you don't have enough hands to constantly steer, trim, peel, reef, eat, sleep, etc.?

What are these guys actually looking for? Max wind compared to the others or nice, steady 20-25kts? Or, do they get to the point where (subject to extremes) wind angle is more important than strength?

Thanks.


The polars are initially the theorectical speed of the boat for a given true wind speed and direction. They are created out of the VPP software packages the designers have, and they assume that the boat has a specific ballast configuration, a specific sail selection, and that you are maximizing trim and helm for speed.

The polars never match the actual potential of the boat and the VPP software struggles for accuracy with specific wind / wave conditions. For example, I almost always exceed my VPP polars going down wind in true wind aft of about 140, and I really can't make my VPP polars in light air (e.g. sub 4 knots) from almost any direction.

Which leads you to start adjusting the VPP polars to reflect actual experience, to develop a set of polars that reflects real life.

You ask about short handing, and the answer is that it is difficult to consistently get to the polars when short handing. The sail change is a good example. In variable conditios when you have already done 3 head sail changes and you would need to make a 4th in order to maximize your speed but are just to knackered and need a short break... well, that would be an example where your polar performance suffers. Fully crewed you wake up the off watch and get the job done. Short handed you whimper at the tiller.

But you absolutely can get to your polars when short handing, and the guys who win are the ones who do it more frequently. I have my polar performance % up on one of my instrument panels all the time, and I measure success by how well I am optimizing.

As for what conditions you are looking for, the easy answer is a broad reach in maybe 120 to 130 true with a big code up, a following swell and blowing 20 true. As the wind speed climbs into the 20's the boat definitely goes faster but the margin for error starts to decrease exponentially. You can also get more speed if the wind goes a bit aft but then you are into kite which requires more vigilence than setting the code and then just focusing on helm and speed trim.

#1493 us7070

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Posted 30 November 2012 - 01:01 AM

Regarding weather models - I am using GFS. We used GFS the couple times we have been in the southern ocean and it is ok - not perfect but none of them are. I am guessing the boats are primarily using the European model - which is not as easy for me to get in grib format. Our experience is that when you are looking out 5+ days you can only use the gross features (the stronger more persistent systems) because the finer features and the exact timing will almost certainly be wrong.


Actually, I would guess they are mostly using GFS

no outside routing assistance is permitted

The race organization sends out a daily weather briefing to all competitors, but it does not appear that this includes any model output.

Otherwise, the competitors are permitted to use only meteorological resources that are free of charge, and publicly available. ECMWF GRIB's are not publicly available free of charge.

I assume these guys are going to be using a global model for most of the race - certainly for where they are now.

whats available?

Canadian model at 1 degree res, but hard to get at sea
UKMet at 2.5 degree res, but also hard to get at sea
NOGAPS at 1 degree
GFS at 0.5 degree and easy to get

#1494 Trickypig

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Posted 30 November 2012 - 02:02 AM

Canadian model at 1 degree res, but hard to get at sea
UKMet at 2.5 degree res, but also hard to get at sea
NOGAPS at 1 degree
GFS at 0.5 degree and easy to get


Very interesting. It would appear the GFS has a chance of modelling the most accurate position of the front?

#1495 Left Hook

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Posted 30 November 2012 - 03:54 AM

I reckon the Puma boys told them all about the great hospitality on Tristan so they are having a mandatory stopover, anchor in the harbour, swim to shore, go to the local pub, try a meal and three beers before swimming back to your boat and resuming the race. I like it.


Round of golf at the Tristan country club?

#1496 popo

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Posted 30 November 2012 - 05:31 AM



Jean Le Cam's 18knts blabla

#1497 Trickypig

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Posted 30 November 2012 - 07:57 AM

Jean Le Cam's 18knts blabla


blabla at 18 knots never looked so easy.

#1498 aquila

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Posted 30 November 2012 - 08:23 AM

arguments against that:
(1) seems like some of them are using handhelds.
(2) tacks and gybes contain confidential or proprietary steps that the teams don't want to reveal
(3) Would you want someone filming you at work?
(4) a lot of the interesting stuff is invisible (ballast tanks, canting keel) or un-interesting to most non-sailors (stacking)

I think there are some vids out there of this done during training that you can find

Some of them are probably filming those maneuvers but:
-it makes a long clip, that need some editing/cutting
-they are too busy or haven't got enough skills for that
-it would be very very expensive and power consuming to send the whole file
-most probably will be edited after the race , or sometime later in the race if they have a break (difficult but not imposible)

For example Bubi sent this one yesterday after climbing the mast 10 days ago , but he didnt have the time to edit it before..

https://www.youtube....h?v=MOlmX4F06o8

looks like they need 18ft skiff style helmet cams or just attach the a pushpit/pulpit.
As for the filming at work its sport isn't it? what makes these guys different? (as a fleet I mean I get some individuals may not want to and that can be part of their personality)
I thought it would really get the physical/sporting part across to the non sailors particularly in our english speaking countries where many people think sailings all gin & tonics and deck chairs, and would be a nice addition to their sitting and talking that we have now.
I wouldn't have thought there would be too much to be kept secret as many boats have sisterships or near sisterships but a well placed cam could avoid this or basic editing.
I figured the greatest expense would be the transmission of it which would mean that editing must be done onboard so i could see that some is filmed and just kept to the end of the race but given that lack of any previous Vendee doco's been uploaded on youtube like the Volvo has done we probably won't see it.

#1499 steinbrenner

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Posted 30 November 2012 - 09:10 AM

so after all those options (west/east, north/south) and guessing which one is paying out, it turns out that rankings are the same as before, jpd turned south sacrificing his ranking but he's second again probably not winning 1st as armel le cleach accelerated again, alex thomson took advantage of it at the moment by jumping on 2nd but he's back to 5th again, same for gabart and stamm

or i'm wrong? is there any adventage of southerly positions of jpd and gabart that they will be able to take advantage of later, like being first to feel new sw breeze?

#1500 Presuming Ed

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Posted 30 November 2012 - 09:46 AM


Canadian model at 1 degree res, but hard to get at sea
UKMet at 2.5 degree res, but also hard to get at sea
NOGAPS at 1 degree
GFS at 0.5 degree and easy to get

Very interesting. It would appear the GFS has a chance of modelling the most accurate position of the front?


Accuracy of resolution =/* accuracy of forecast.
(*necessarily)

Is there somewhere to get real time sat photos?

Posted Image


ETA - this isn't too bad.

http://www.sat24.com...e=false&index=9




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