Facebook

Login

Support Sailonline

If you haven't already - join the SAILONLINE YACHT CLUB!

Please also consider making a donation - all amounts are greatly appreciated!

Profile for jakob



Name jakob
Email Address jakob@sailport.se
AvatarUsers avatar
Posts364
Board Signature
...one of the guys behind the game...
  • 2011-06-06 06:56:28
    Re: IMSYC 2011
    Board » General Discussion
    You people are fantastic! What enthusiasm and engagement!!! I will try to get some students to this thread. :-)
    ...one of the guys behind the game...
  • 2011-05-02 06:35:10
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    You find them in Homework set 5 and 6.
    ...one of the guys behind the game...
  • 2011-05-02 06:08:28
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    ...and if you want to play around with hull shapes etc to investigate effects on CP, trim, stability etc you might want to try the msy_hydrostatics-code that I put on the same web-page. The code lets you import hull shapes and then stretch them in various ways :-)
    ...one of the guys behind the game...
  • 2011-05-01 18:35:20
    Re: IMSYC / SOLstice Cup
    Board » General Discussion
    Regarding IMSYC: If you are interested in the rule for the IMSYC race 2011 you can find it here http://www.kth.se/polopoly_fs/1.47075!IMSYC-66%20rule.pdf
    I have about ten students designing boats for the race :-))

    /Jakob
    ...one of the guys behind the game...
  • 2011-01-15 12:33:46
    Re: Leg 2 IMOCA Global
    Board » Flag Officers » Races
    Hi

    As always in SOL: Changing course, maps etc in the middle of a race is generally a bad idea. Main reasons are:
    1) the communication problem. How do we make sure that we reach all boats with the info?
    2) We have very little control over when the changes become visible in the clients. Often, a clear-cache is needed (or long time).

    I vote for not changing courses etc unless absolutely vital.

    /Jakob
    ...one of the guys behind the game...
  • 2010-12-06 19:48:24
    Re: NOAA vs SOL weather
    Board » Technical Support
    ...well you should be careful with those softwares... especially when there is a Sailplanner available for free ;-)
    ...one of the guys behind the game...
  • 2010-12-05 20:58:26
    Re: NOAA vs SOL weather
    Board » Technical Support
    Hi all,

    You are basically all correct :-) I am the first to admit that there are many ways of doing this and that we did not spend weeks of thinking when choosing algorithm - but it works. Also (Hubert) the game winds will only correspond exactly with the GFS-forecasts when the time is exactly the time of a certain forecast frame and the point of the "observation" is exactly that of a forecast nodal point. Thus, colour coding would not be of any use at all...

    Why this attention? Is it just curiosity or weather-rounting ?

    Regards
    Jakob
    ...one of the guys behind the game...
  • 2010-12-03 16:17:40
    Re: NOAA vs SOL weather
    Board » Technical Support
    Hi

    So, about the interpolation of weather in time and space :-) Maybe some out there is longing for a short one-liner as explanation but I am afraid there is a little more to it… Here is in short the steps we take to get an "observation" (as we call it) at an arbitrary time (called t) and location based on forecasts.

    1) Find the two forecast time steps (here called t1 and t2) surrounding the time t.
    2) In space we simply use linear interpolation (in the 2 dimensions lat/long) of the forecast-data in the 4 closest forecast-nodes in the grib-file. Since the forecast has separate fields, one for northerly wind and one for easily wind we need to treat these entities separately, in our case by using complex notation. We also need to do this for both frames t1 and t2 from step 1 which thus gives us a set of two complex-valued space-interpolated wind speeds, one at t1 and one at t2.
    3) Now we need to interpolate in time as smoothly as we can. We chose to do this using simple shape functions ensuring continuous wind speed and actually in our case continuous time derivatives.

    Now, there are naturally many ways of doing this. One draw-back of this kind of interpolation is that we loose energy. Imagine the situation with constant wind speed but rotating wind direction so that at t1 the wind is due easily and at t2 it is due westly. In our interpolation we would (falsely) get that the wind speed at the time (t1+t2)/2 would be zero.

    Also note that we do not always use the GFS model from NOAA. In particular around Sweden we have more detailed forecasts.

    Hope this helped a little.

    Regards
    Jakob
    ...one of the guys behind the game...
  • 2010-09-19 15:00:56
    Re: OCTOBER 2010 - draft calendar
    Board » Flag Officers » Race Calendar
    Hi.

    We all remember the Irish-rock episode. The problem that time was the unauthorized use of protected brand names. From that point in time SOL has been, and will continue to be, careful and considerate in terms of naming races. However SOL is not by any means scared of racing between locations in the geography where others, IRL or virtually, also race. Until proven wrong SOL is of the opinion that it is totally ok for anyone to race "similar time-similar route" as IRL-races. No-one has ever raised any legal aspects regarding this. However I do want to point out that if SOL administrators (Godesses etc) do not see that a certain race fits the calendar it is up to the community to argue and be sugary :-)) Happy sailing /Jakob
    ...one of the guys behind the game...
  • 2010-06-28 14:46:05
    Re: Rename boat
    Board » Technical Support
    Done :-)
    ...one of the guys behind the game...

Races

Next Race: 00d 00h 00m

Current Races:

Red Eye - Bimini Beach Run 2025

This time of year, already it is balmy in the Bahamas and the Biminis, if ever it is not; so let’s try and get some “Red Eye” enjoying the fine weather and a warm night, racing our appropriately luxurious and bombastic Gunboat 90, as always our craft of choice for this 250nm beach-running, island-hopping SOL classic through this multihull mecca!
Race #1845
INFOby brainaid.de
GB 90 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - RED
Race starts: May 21st 12:00 Registration will open soon
▶ Flash
GO TO RACE

Africa by Sea - Abidjan to Swakopmund


Our exploration of Africa by Sea continues. Next, it’s off to Swakopmund, on the water’s edge of the Kalahari desert. It’s a wind-blasted coast, and a venue of choice for those seeking to set wind-powered speed records. More likely than not, we’ll have to beat into it in our Steinlager II, to finally find some shelter behind the walls of Platz am Meer where there is a marina of sorts. Only 2200nm!
Race #1856
INFOby brainaid.de
Steinlager II PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - ABS
Race starts: May 14th 17:00 Registration Open!
▶ Flash
GO TO RACE

Newport to Annapolis 2025


The Newport to Annapolis race, first held in 1947, is one of the most historic and well-known US East Coast blue water races. Linking two seaports dating from the US nation's birth, Annapolis and Newport, the race contrasts the country's largest estuary, the Chesapeake Bay, and the Atlantic Ocean. Since 1969, the route has run from Annapolis through the Chesapeake Bay to Newport. The SOLers will sail 470nm in their Carkeek40s in the original direction from Newport to Annapolis, including the Chesapeake, which is such a daunting challenge that the 1997–98 Whitbread Round the World Race for the Volvo Trophy added it to the course, as did the Volvo Ocean Race in 2002 and 2006.
Race #1912
INFO from brainaid.de
Carkeek 40 PARTICULARS
WX Updates:
0245 / 0845 / 1445 / 2045
Ranking:
ARQ2 - ARCH - SUPSOL – SYC
RACE CLOSE: Tuesday,
May 20 at 2300 UTC.
Race starts: May 12th 17:00 Registration Closed
▶ Flash
GO TO RACE

Channel Islands TIMED Chase 2025

Join us in Saint Peter Port, Guernsey for a race around the Channel Islands in the J-109, a recent addition to the Sailonline fleet. The course takes us around the islands of Alderney and Jersey finishing back in Saint Peter Port. This is a TIMED race, so you may RE-REGISTER HERE to try again, after finishing a run. You will have 13 days and 11 hours to test your skill and decision making after the race opens.
Race #1915
INFO by brainaid.de
J-109 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ2 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
24 May at 23:00 UTC
Race starts: May 11th 12:00 Registration Open!
▶ Flash
GO TO RACE

Elephant Island to Marquesas 2025

Prepare to test your limits as we launch into the third leg of the RWW Series and the fifth leg of the 2025 Ocean Championship Series—an epic voyage from Elephant Island to the Marquesas in the heart of French Polynesia. This 4,700-nautical-mile challenge is a true test of endurance, strategy, and raw sailing adrenaline. Aboard the high-performance Volvo 70v4, competitors will face fierce headwinds as they round the legendary Cape Horn and make the thrilling transition from the Atlantic to the Pacific. Do you have what it takes to conquer the Pacific? Join us, and put your skills to the ultimate test.
PRIZE: SMPF
Race #1909
INFO by brainaid.de
VO70_v4 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ2 - RWW - OCCH - SUPSOL - SYC
Race starts: May 05th 11:00 Registration Closed
▶ Flash
GO TO RACE

Sinbad by Balloon 2025 - Toamasina to Baia de l'Oiseau


You may recall that when last we visited Madagascar in the company of Sinbad, the Sultan commanded our intrepid inspirator to seek out fabled islands where in Summer the sun barely set. We did and we returned but the Sultan wasn’t happy with Sinbad’s report, so here we go again, now by SOL Balloon instead of sailing vessel. Expect to be in the air for at least 2100nm and depending on how the wind brings us, anything between two weeks and two months before we shall descend at the Sultan’s given coordinates!
Race #1884
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - SBB
RACE CLOSE: Sunday,
May 18 at 2300 UTC.
Race starts: Apr 09th 11:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member WRmirekd
  2. Sailonline Yacht Club Member Patrick70119
  3. Sailonline Yacht Club Member CriticalHippo
  4. Sailonline Yacht Club Member KaSToR
  5. Sailonline Yacht Club Member FreyjaUSA
  6. Sailonline Yacht Club Member rafa
  7. Sailonline Yacht Club Member Kipper1258
  8. Sailonline Yacht Club Member bonknhoot
  9. Sailonline Yacht Club Member rumskib
  10. Sailonline Yacht Club Member vida

View full list

Series

Mobile Client

SYC members have the benefit of access to our mobile/lightweight web client!

The mobile client