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 » Sailing TWA vs Compass Course in backing wind

Posted by
Chappo


Users avatar

Posts
53
Registered at
2009-04-17 12:00:35
2009-08-11 01:36:37 - Sailing TWA vs Compass Course in backing wind
I would expect the expert IT and yachting technos know the answer and I believe the answer is linked to the polar performance but presuming the polar shows a steady increase in speed as TWA increased. I am interested to know that if you are sailing at say 50 deg TWA and sail into a backing wind, is it quicker to reach a point to sail TWA and then adjust to say 45 TWA to reach the point or to sail in compass increments of 50,49,48,47,46,45 TWA.
Posted by
NZL_PaulR


Users avatar

Posts
311
Registered at
2008-07-22 12:21:30
2009-08-11 01:54:28 - Re: Sailing TWA vs Compass Course in backing wind
A definate maybe, becoming a perhaps and possibly developing into "most Likely".

It depends upon the speed of wind change vs the performance drop from large course changes vs the hours available for SOL.

In my case, because SOL is my home page, I can check often, perhaps too often, but then again, when I sleep, I go aground, also far too often!

Look at your VMG when changing courses.

Sailing a cc is necessary if winds are changing and freeing for your current tack because speed is generally improving.

If winds are heading, the same TWA will main tain a speed, but your course will swing.

TIP: It can be a good idea when on a CC course to use the "wheel" and overlay your existing course but then set the TWA.
Now your predicted course will ben "bent", sometimes helpfully, but according to Plato's Rule, 80% of the time it will bend the wrong way.

Forrest Grump said "Shit Happens!"

. . . and then there is sailing

My $0.02c worth
If it breaks, it's not strong enough!
Posted by
Chappo


Users avatar

Posts
53
Registered at
2009-04-17 12:00:35
2009-08-11 02:30:30 - Re: Sailing TWA vs Compass Course in backing wind
Thanks Paul, that was more like $5 worth. As you say the VMG is also quite relevant although it changes in slow increments unlike the boat speed which moves quickly. I am also curious when setting a best VMG when working, for the the same VMG number do you choose the highest BS setting, the lowest BS setting (to get best VMG hidden decimal places!!??) or go for a middle setting. I find the middle setting seems best.

What yacht are you helming?

Peter (Chappo)
Posted by
NZL_PaulR


Users avatar

Posts
311
Registered at
2008-07-22 12:21:30
2009-08-11 02:41:59 - Re: Sailing TWA vs Compass Course in backing wind
Middle = Highest VMG and hopefully the distribution graph is not skewed too much.

NZL_PaulR
If it breaks, it's not strong enough!
Posted by
Chappo


Users avatar

Posts
53
Registered at
2009-04-17 12:00:35
2009-08-11 02:57:30 - Re: Sailing TWA vs Compass Course in backing wind
Thanks for VMG confirmation.

Ahh a Kiwi. I was born in Greymouth (well described as the least pretty town in NZ) but left in a flying boat when old enough to fly at 6 weeks so now officially an Aussie. Been back a few times for skiing, yachting, gliding at Omarama.

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Panama Canal 2026


Sailing in the Panama Canal isn't the best idea, and organizing a race there is simply impossible and unfeasible IRL. In SOL, we have slightly different rules, so why not? A 36nm, frantic race awaits us, and the fast Dehler 30 OD will help us navigate the Panama Canal with grace.
Race #1999
INFO by brainaid.de
Dehler30 OD PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
SPQ1 - SPCH - SYC
Race starts: Jan 03rd 13:00 Registration will open soon
▶ Flash
GO TO RACE

Tasman Double 2025 - Hobart to Sydney

With Hobart astern and celebrations behind them, the fleet turns north for Leg 2 of our Tasman Double Series. Over 625 nautical miles, our SOLers aboard their mighty Super Maxi 100v2s return to the Tasman Sea, where shifting weather, demanding seas, and nonstop decisions shape every mile. The race back to Sydney rewards those who read the conditions best, manage their speed wisely, and stay focused until the final approach.
Race #2000
INFO by brainaid.de
Super Maxi 100v2 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TD - SYC
Race starts: Jan 02nd 02:00 Registration Open!
▶ Flash
GO TO RACE

Cape Town to Rio 2026

Welcome to South Africa and RCYC's classic transatlantic Cape2Rio Race from Cape Town, South Africa, to Rio de Janeiro, Brazil. First run in 1971, this run is buddied with the IRL, Cape2Rio 2025 arranged by the Royal Cape Yacht Club with the cooperation of the
Iate Clube do Rio de Janeiro Despite this being announced the 2025 race (starting dec. 27) it is the 2026 SOL championship kickoff. This virtual version, will be raced once again in Mark Mills' 74ft speedster, the stunning C2R74.
Race #1996 INFO
by brainaid.de
C2R74 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
OCQ1 - OCCH - SUPBUD - SYC
Race starts: Dec 27th 12:00 Registration Open!

▶ Flash
GO TO RACE

ORCV Melbourne to Hobart 2025

Welcome to the legendary Westcoaster, a true test of endurance and seamanship that’s challenged sailors for over 50 years! Spanning 435 nautical miles, this iconic race takes the fleet from Melbourne, across the wild Bass Strait, and around Tasmania’s rugged west coast to Hobart. Organized by the Ocean Racing Club of Victoria, this year our SOLers will be racing the sleek and powerful Dehler 46—a fast, elegant regatta cruiser built for both speed and adventure. Get ready for an unforgettable offshore classic!
Race #1952
INFO by brainaid.de
Dehler 46 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
RACE CLOSE: Friday,
January 2 at 2300 UTC.
Race starts: Dec 27th 02:30 Registration Closed
▶ Flash
GO TO RACE

Tasman Double 2025 - Sydney to Hobart

Christmas in Summer? Indeed! Kick off the first leg of our two-leg Tasman Double series in the classic 625nm Sydney to Hobart race, this year in the upgraded SuperMaxi 100v2. Inspired by Neville Crichton’s legendary Alfa Romeo II and her near-sister Wild Oats XI, these yachts blaze across online and real-world waters alike. Feel the thrill even in storm-force winds as you tackle the Tasman Sea—dock in Hobart victorious, or at least in time for a well-earned post-Christmas drink!
Race #1953
INFO by brainaid.de
Super Maxi 100v2 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: TD - SYC
RACE CLOSE: Saturday,
January 3 at 2300 UTC.
Race starts: Dec 26th 02:00 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 CriticalHippo
  4. Sailonline Yacht Club Member rafa
  5. Sailonline Yacht Club Member vida
  6. Sailonline Yacht Club Member bonknhoot
  7. Sailonline Yacht Club Member CollegeFund
  8. Sailonline Yacht Club Member Sax747
  9. Sailonline Yacht Club Member rumskib
  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