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 » Technical Discussion » Performance loss

Page: First Previous 7 8 9 10 11 12 13

Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2016-11-24 19:41:00 - Re: Performance loss
I hate to play the ignorant here, but at the level of my SOLing, I do not particularly care about the distance lost by tacking or gybing--they are inevitable!!!
What I need is a quick 'graphical' method of determining the perf loss I will suffer when I round a mark that I am approaching. I want to know what perf loss I will have--and if it is greater than 7% (which will reduce my perf below 93%)---what angle do I need to turn to make the first part of a two-part turn give me a perf loss of slightly less than 7%? I can then complete my turn without incurring further perf loss. This works directly as stated, only for gybes...???
You state that, when tacking, the perf loss is equal to half of the new boat speed. This is not helpful, as I do not know what my new boat speed will be until I know the perf loss. (This is a circular argument!)
What I need to know as I approach a position or a mark, at which I will tack, is a way to determine quickly if my perf loss will be more than the 7% level, and if it is, to what angle should I make the first part of my tack, so that I may complete the rest of the tack with no further increase in loss.
I realise, that whatever my total perf loss from my tack, I will pay the penalty of 'distance and time lost'--there is nothing I can do about that!!!

--- Last Edited by Rod at 2016-11-24 20:03:36 ---

--- Last Edited by Rod at 2016-11-24 20:04:25 ---
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
2016-11-24 20:22:45 - Re: Performance loss
The boatspeed that is used to calculate the performance loss after a change of tack is the boatspeed on the new course with 100% performance (this might not be clear from the document).

You want to know how much you loose when you have a choice. For example "gybe directly" vs "gybe with an extra command", or "tack every 2 minutes along the shoreline" vs "tack every 30 seconds along the shoreline". Distance lost or time lost can help with a rough estimate of how much you gain/loose with either option.

The more exact option is to look at the average VMC during the manoeuvre (as long as the time interval are the same). To use this, you need to fully understand sailing with VMC, as outlaw explains in his solfans posts.

The main purpose of having performance loss is to make skippers decide between things like "tack every 2 minutes along the shoreline" vs "tack every 30 seconds along the shoreline" and choose the realistic option because it's fastest. We've seen that the current performance model fails in this regard when the boats are on the extreme ends of the scale (AC72, DN, Square Rigger).
The current performance model has as a (in my opinion, unwanted) side-effect that the way we tack/gybe our boats can have a large influence on performance loss.

Anyway, I hope I cleared up the circular reasoning (which can actually be solved with some math, but why bother, it's not necessary anyway) and I hope you understand (to the extend you want to) the importance of "distance lost" and/or other metrics to quantify the losses the are the result of particular manoeuvres.

--- Last Edited by kroppyer at 2016-11-26 01:00:26 ---
Posted by
Rod


Users avatar

Posts
392
Registered at
2010-06-24 22:30:48
2016-11-25 21:53:53 - Re: Performance loss
I am starting to follow your reasoning about the Perf loss while tacking or gybing. However, at this point in my practice, you are one step ahead of me still. So far, I am still at the stage of trying to keep my perf loss to a minimum. At lower boat speeds most of these manoevers can be carried out while still keeping the loss to 7% or less. It is only at higher speeds that a course change can result in a loss greater than 7%. My concern then becomes my efforts to reduce this loss to as close to 7% as possible by tacking or gybing in a double action, so that the second part of the action will result in no further increase in loss.
I have not yet reached the degree of sophistication where I start to worry about a choice of how much I am able to minimise the losses in a series of tacks or gybes in quick succession.
I will attempt to extend my thinking to such operations as multiple tacks along a shoreline (which I have observed being done without clearly understanding "why").

--- Last Edited by Rod at 2016-11-25 21:56:32 ---
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
2016-11-26 01:00:09 - Re: Performance loss
A series of tacks (along a shoreline) is not to minimise performance loss.

In a right shift, you are best of being the rightmost boat (within the laylines*). Sometimes a landmass is in the way of being the rightmost boat and you have to tack to keep clear. Question is, how long do you keep on sailing in the wrong direction before tacking back to the right? For this you need to know two things:
- how much am I losing by sailing in the wrong direction?
- how much am I losing by tacking?

The second one requires an understanding of the performance loss model, even when you are in no way trying to "cheat" the model with fancy manoeuvres/tricks.

One simple tactic: when your performance is enough below 93% (after beaching for example), you don't lose anything with two additional tacks to bring you more to the right: you are free to tack very quickly along the shoreline until your performance is over 93% again. The tricky thing here is to avoid another bbq, and you're usually not wining much anyway.

(* typically just outside the laylines actually, but that's besides the point here)
Posted by
Schlumpi


Users avatar

Posts
2
Registered at
2016-07-22 08:14:22
2017-01-16 05:03:49 - Re: Performance loss
Kroppyer (and others). This is a very important thread, about a topic often poorly understood by newbies - I still consider myself one of them.

Is there any timeline being proposed for the changes to PL (and recovery)? It does seem well overdue. I will not add my 2c to the "way to change" argument.

A thought I would like to add is to add some light info to the Manual in Section 1.9 - a brief explanation of what happens and how to minimise it. Perhaps a link to a page with more info. The piece Yohann wrote in his post in this thread on 2016-05-06 16:01:13 is perhaps the most elegant I have come across.

A quick "Thank you" to all in the SOL community who work so hard to maintain and improve this simulator :)

Posted by
PresentTense


Users avatar

Posts
1
Registered at
2017-05-03 02:18:44
2017-05-04 01:12:27 - Re: Performance loss
I'm new to SOL and quite frankly, this thread makes me not want to be involved. Along with another aspect that I believe exists, which is account sharing?

I understand the idea of performance being lost through a tack or gybe, but does it really make a difference to who wins or loses a real ocean race?

The fact that it is being used in the way described in this thread makes me think the whole game is broken. IMO it would be better to have no Performance Loss at all than to have people gaining a competitive advantage from abusing it. And the answer is "well, anyone can work it out and use it for themselves, so that means its okay..."
No, it's not. It's Cheating.
Posted by
kroppyer


Users avatar

Posts
347
Registered at
2010-02-05 15:25:55
2017-05-04 10:39:21 - Re: Performance loss
Hi PresentTense,
Welcome to sailonline! You have very quickly discovered what I think is the worst aspect of sailonline. Performance loss usually does not really play a role in race on sailonline, but some of the shorter races (sprints/timed races), or those with special circumstances (sailing with tallships, weather that gives a large advantage to hugging the coast, etc.) sometimes bring out the worst of the current implementation of performance loss. In those cases people with a full understanding of how performance loss works in sailonline can leverage their knowledge to gain an advantage over the competition. Of course people with more knowledge and experience should have an advantage over the competition, but this type of knowledge has nothing to do with sailing, so it shouldn't give an advantage. I think everyone would agree. We need to change this.

So yes, for most of the races (esp. the ocean races) it doesn't really make a different whether or not we have performance loss. But by disabling it, there will be a small number of cases where the fastest route includes tacking/gybing every 10 seconds. Performance loss takes solves almost all of this small number of cases, but as a side effect introduces a smaller number of cases where performance loss itself has an undesirable effect on racing.

I think the current performance loss is better than no performance loss, but it could definitely do with some improvement. I'm convinced we can make performance loss better, meaning: it prevents tacking/gybing every 10 seconds in all cases and it has less side effects.

I really hope the current performance loss implementation doesn't affect your enjoyment of the game/simulation. In normal ocean racing is only very rarely that people with a full understanding of performance loss can use it to their advantage (to gain 10 or 20 seconds).

Page: First Previous 7 8 9 10 11 12 13

Please login to post a reply.

Races

Next Race: 00d 00h 00m

Current Races:

Regata dell’Accademia Navale 2025

Welcome to Sailonline’s first partnership with the City of Livorno, in cooperation with the local yacht clubs and the Italian Navy, to offer you the online opportunity to race the Regata dell’Accademia Navale. 630nm in length, starting and finishing in Livorno, the race takes you the length and breadth of the Tyrrhenian Sea via Porto Cervo and Capri. Online, you will be sailing a Class 40, which should keep you well in with the top of the real-life fleet which we will be tracking on screen!
Race #1902
INFO by brainaid.de
Class 40 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
Race starts: Apr 26th 10:00 Registration Open!

▶ Flash
GO TO RACE

Gulf of St Lawrence 2025


The Gulf of St. Lawrence, with one of the largest and deepest estuaries in the world, will be the site of a completely new race in SOL. Our Melges 40 will take us 950 nm from Bathurst in Baie des Chaleurs around the islands of Anticosti, Pelee and Prince Edward admiring beautiful landscapes along the way. Fair winds.
Race #1910
INFO from brainaid.de
Melges 40 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
ARQ2 - ARCH - SUPSOL – SYC
Race starts: Apr 21st 17:00 Registration Open!
▶ Flash
GO TO RACE

Transat à Deux 2025

Above you see a single-handed sailor semi-foiling his Beneteau Figaro III to the horizon. It is in fact Ireland’s Sailor of the Year and the overall winner of last year’s Solitaire du Figaro, Tom Dolan. Somehow, we got our hands on a polar for the Class, and rather than trying to surreptitiously track Tom and his mates in the 2025 edition of the Solitaire, sailing rather-short, single-handed legs across the Celtic Sea and Biscay, we thought we’d see how our virtual craft would fare on the Class’s double-handed 3900nm Trans-Atlantic, from somewhere in Brittanny to somewhere in the Caribbean via somewhere in the Canaries. Allez, mes braves!
Race #1901
INFOby brainaid.de
Figaro III foil PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
Race starts: Apr 20th 11:00 Registration Open!
▶ Flash
GO TO RACE

Bahamas and Back TIMED Race 2025

Welcome to sunny South Florida for this race that has us crossing the Gulf Stream twice. We depart from Palm Beach for a short run over to Freeport, Bahamas then it’s on to Miami before heading to the finish line back in Palm Beach. 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 #1911
INFO by brainaid.de
Santa Cruz 70 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
TRQ2 - TRCH - SUPSOL - SYC
RACE CLOSE: Saturday,
26 April at 23:00 UTC
Race starts: Apr 13th 12:00 Registration Open!
▶ 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 starts: Apr 09th 11:00 Registration Closed
▶ Flash
GO TO RACE

Valparaiso to San Francisco 2025

Get ready for an exhilarating new challenge as we set sail on the fourth leg of the 2025 Ocean Championship Series! Following in the 19th century footsteps of Isabel Allende's heroine, Eliza Sommers, 'Daughter of Fortune', this all-new route takes us across the vast eastern Pacific, from Valparaíso, Chile, to San Francisco, California - a 3500nm journey of endurance, strategy, and pure sailing adrenaline. This leg will be raced aboard the powerful Rapido 60, pushing sailors to their limits as they navigate the open ocean. Do you have what it takes to conquer the Pacific? Join us and put your skills to the ultimate test!
PRIZE: SMPF
Race #1900
INFO by brainaid.de
Rapido 60 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: OCQ2 - OCCH - SUPSOL - SYC
Race starts: Apr 07th 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 KaSToR
  4. Sailonline Yacht Club Member CriticalHippo
  5. Sailonline Yacht Club Member vida
  6. Sailonline Yacht Club Member FreyjaUSA
  7. Sailonline Yacht Club Member rafa
  8. Sailonline Yacht Club Member Kipper1258
  9. Sailonline Yacht Club Member bonknhoot
  10. Sailonline Yacht Club Member rumskib

View full list

Series

Mobile Client

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

The mobile client