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!

Board » General Discussion » TWA as the angle to the wind?

Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2014-06-28 13:39:38 - TWA as the angle to the wind?
Having been caught out by changes in the wind direction overnight, prior to a very early morning start time, I would like to suggest a small addition to the options available for course setting.
Is it possible to have a third option, in addition to the CC and TWA, in which an "angle to the wind" can be selected that does not refer to any specific wind direction?
This way, if the wind direction in the Wx changes, during the night, (or while the SOLer is away from his/her computer) the boat will start at a specified angle to the new wind direction, rather than to the compass course TWA to the old wind direction.
If it breaks, it's not strong enough--if it doesn't, it's too heavy.
Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2014-06-28 16:36:11 - Re: TWA as the angle to the wind?
So, a cc command based on the twd at the time of execution? What the command does at execution is basically, putting the given value in the twa box then selecting cc and then pressing "send command"?

So, you would be happy with the following:
a command: "switch", which switches your boat from twa to cc, or from cc to twa without changing course. That means that your proposed command will look like to following:
12:00:00 twa 45
12:00:15 switch (to cc)

I'd like that.

When we have that, it would be nice to have some other way to trigger the switch command, like "when twa<45, switch (to twa)". And using those triggers for other commands will be very useful too: "when cc=200, tack".

I like that too!

Of course, another trigger would be based on your position: "when on layline, tack", "when at mark, cc=200"

Oh wonderful!

When you're doing that, using waypoints comes into play. And you can think of a lot of new commands based on combinations with waypoints and cc/twa/switch commands that will come in handy.

Many new options!

Question is, do we want all that, when you understand it all, it might make life easier, but many will argue that, instead of making it easier, it is making it more complex, with all the new options.

Maybe a bit too much options...

All in all, things like this will forever change the game and are not to be thought about very lightly.
Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2014-06-28 17:17:22 - Re: TWA as the angle to the wind?
What I was thinking about was a TWA angle to the wind only at the time it is executed at the START. I note that many boats start in directions that do not make much sense. I have wondered if the cause was that the commands were set long before the actual start and the Wx has changed substantially in the intervening time.
I agree that such a command option, if effective DURING the race, would substantially alter the DC process in ways that we may not desire.
If it breaks, it's not strong enough--if it doesn't, it's too heavy.

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

PIC Coastal Classic Yacht Race 2025

Welcome back to Auckland for the 2025 PIC Coastal Classic! In partnership with the New Zealand Multihull Yacht Club, Sailonline is thrilled to race this iconic 118nm dash to Russell. First sailed in 1982 and inspired by early powerboat runs, it’s now a legendary multihull showdown. This year we race Ocean 50 foiling trimarans—fast, agile, and built for offshore performance. Expect tactical challenges, adrenaline-fueled downwind legs, and nail-biting lulls. Finish line rewards? Bacon butties, rum, and bragging rights in beautiful Russell!
Race #1950
INFO by brainaid.de
Ocean 50 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
Race starts: Oct 24th 22:30 Registration Open!
▶ Flash
GO TO RACE

Port Huron to Mackinac 2025


First run in 1925, the race from Huron to Mackinac is considered to be the world's longest consecutively run freshwater sailing race. Let's go - 260nm in X-362 Sport's awaits!!
Throw away unnecessary ballast from your boats. Fresh water has less buoyancy, which means greater draft and greater resistance to movement, which means lower speeds, etc.😊
Race #1959
INFO from brainaid.de
X-362 sport PARTICULARS
NAM_AWIP WX Updates:
0245 / 0845 / 1445 / 2045
Ranking:
ARQ4 - ARCH - SUPSOL - SYC
RACE CLOSE: Monday,
October 27 at 2300 UTC.
Race starts: Oct 20th 17:00 Registration Open!
▶ Flash
GO TO RACE

Sinbad by Balloon 2025 - Carnarvon to Dondra


From here, our home in Bharatavarṣa is now north west of us – said Sinbad to his fellow balloonists. Perhaps we can ride the wind first further north, and then catch the winds that every year bring the rain, perhaps not. It’s 2600nm and we could be aloft awhile, so, Master el-Quarters, victuals only, no sandbags, provisioning the giant hamper. It will be not a picnic!
Race #1886
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC - SBB
Race starts: Oct 15th 11:00 Registration Closed
▶ Flash
GO TO RACE

Alicante TIMED Race 2025

Welcome to beautiful Alicante on Spain’s Costa Blanca. Dine on some local tapas and paella before racing your America’s Cup foiling winged-sail AC72 catamaran on this 208nm race out to and around Isla de Formentera returning to Alicante after rounding the mark at Cap de la Nau. There should be some very fast times! This is a TIMEDrace so you may RE-REGISTER HEREto 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 #1958
INFOby brainaid.de
AC72v2 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ4 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
25 October at 23:00 UTC
Race starts: Oct 12th 12:00 Registration Open!
▶ Flash
GO TO RACE

Marion Island to Fernando de Noronha 2025

The adventure continues as we launch the next to last leg of the RWW series. This leg takes us from Marion Island to Fernando de Noronha, an island in the world heritage archipelago with the same name, 220 nm off the coast of Brazil. This race doubles up as #7 of RWW and #10 of OCCH. A 4400 nm journey of endurance, strategy and pure adrenaline. The RWW series is as whole, part of the 2025 ocean championship. Get ready for this exhilarating challenge as we set sail on the third to last leg of the 2025 Ocean Championship Series! This leg will be raced aboard the Judel Vrolijk 62, pushing sailors to their limits as they navigate the open ocean. Do you have what it takes to conquer the Southern Atlantic? Join us and put your skills to the ultimate test!
PRIZE: SMPF
Race #1955
INFO by brainaid.de
JV 62 PARTICULARS    
WX Updates:
0430 / 1030 / 1630 / 2230    
Ranking: OCQ4 - RWW - OCCH - SUPSOL - SYC
RACE CLOSE: Thursday,
October 30 at 2300 UTC.
Race starts: Oct 06th 11:00 Registration Closed
▶ Flash
GO TO RACE

Camel or Balloon 2025 - Khartoum to N'Djamena


As there is a lull in the calendar, your PRO has decided to risk an experiment – a balloon race over land, using a workaround to eliminate the recognition of water/land transitions. If it fails, the server may crash, and we abandon PDQ, hopefully after leg 7 of the ABS race to Suez has been decided, and before the start of the 1st OCC of Q4. Camel or Balloon – c 1000 nm from a field on the north bank of the Blue Nile at Khartoum to a field on the north bank of the Chari River at N'Djamena!
Race #1956
INFOby brainaid.de
SOL Balloon PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: none
RACE CLOSE: Sunday,
October 26 at 2300 UTC.
Race starts: Sep 28th 09:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member KaSToR
  2. Sailonline Yacht Club Member vida
  3. Sailonline Yacht Club Member WRmirekd
  4. Sailonline Yacht Club Member CriticalHippo
  5. Sailonline Yacht Club Member rafa
  6. Sailonline Yacht Club Member CollegeFund
  7. Sailonline Yacht Club Member Kipper1258
  8. Sailonline Yacht Club Member BRENTGRAY
  9. Sailonline Yacht Club Member Panpyc
  10. Sailonline Yacht Club Member Sax747

View full list

Series

Mobile Client

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

The mobile client