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:

Cross the Convergence 2026 - Guam to Ouvéa


The third race of our series of ocean voyages across the World’s convergence zones takes us southeastward now down the Pacific, from Guam’s Apra Harbour at 13.5 degrees North, back across the Equator to the glorious New Caledonian resort island of Ouvéa, on the edge of the Tropic of Capricorn at 20.5 degrees South. It’s 2400nm, and there’s more than a few other islands in the way, so mind where you go in your Ocean 50s. Race #1981
INFOby brainaid.de
Ocean 50PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: CCZ - SYC
Race starts: Mar 20th 18:00 Registration Open!
▶ Flash
GO TO RACE

Lake Victoria TIMED Race 2026

This month’s TIMED race takes us inland to Lake Victoria in the heart of Africa. Starting at Rosebery Channel in Uganda sail the AC72v2 on a 196nm course around Bugala Island on the way to the finish line in Tanzania’s Speke Gulf. 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 #2018
INFOby brainaid.de
AC72v2 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ1 - TRCH - SYC
RACE CLOSE: Saturday,
28 March at 23:00 UTC
Race starts: Mar 15th 12:00 Registration Open!
▶ Flash
GO TO RACE

SSANZ Round North Island Race 2026 - Leg 4

The final challenge awaits in Leg Four of the Round North Island Series! From Napier, the fleet sets off on a 354 nautical mile run back to Auckland, completing the full circumnavigation where the journey began. Fatigue may be setting in, but this last leg could decide the overall standings. Sailing the fast and responsive Sun Fast 3600, our skippers will need sharp tactics and steady focus to finish the series strong and claim victory!

The start time for this race may change at short notice to align with the real race. The confirmed start date and time will be announced via an in-race “L” flag message — Please monitor race communications closely.
Race #2014
INFO by brainaid.de
Sun Fast 3600 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: RNI - SUPBUD - SYC
RACE CLOSE: Friday,
March 20 at 2300 UTC.
Race starts: Mar 12th 22:00 Registration Closed
▶ Flash
GO TO RACE

Iceland to the Falklands 2026

Welcome to an all-new route, the first of three Round the 'Old World' of Europe, Africa, Australia and Asia. To give each leg of the ROW a bit of length we'll try to hug the coasts as little as possible, so starting in Iceland our first leg of the series, which will also be the final leg of our Quarter 1 Ocean Championships takes us 7200nm to the Falklands, the full length of the Atlantic end to end. To make sure we'll get it done within the month we'll be sailing our Maxi Trimaran.
Race #2010
INFO by brainaid.de
Maxi Trimaran PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ1 - ROW - OCCH - SYC
RACE CLOSE: Tuesday,
March 24 at 2300 UTC.
Race starts: Mar 02nd 11:00 Registration Closed
▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member KaSToR
  2. Sailonline Yacht Club Member WRmirekd
  3. Sailonline Yacht Club Member rafa
  4. Sailonline Yacht Club Member rumskib
  5. Sailonline Yacht Club Member Sax747
  6. Sailonline Yacht Club Member CriticalHippo
  7. Sailonline Yacht Club Member vida
  8. Sailonline Yacht Club Member CollegeFund
  9. Sailonline Yacht Club Member Panpyc
  10. Sailonline Yacht Club Member sassy63

View full list

Series

Mobile Client

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

The mobile client