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

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.
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 ---
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.
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)
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 :)

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.
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:

San Diego Islands Race 2021

Sailonline is partnered with San Diego Yacht Club for the 2021 Islands Race. This year we are racing TP52s to compete against the real crews in the 132nm course from Long Beach, around the Catalina Islands to San Diego.
Race #1435
INFO by brainaid.de
TP52 PARTICULARS
NAM_AWIP WX Updates:
0245 / 0845 / 1445 / 2045
Ranking: SYC
Race starts: Mar 05th 21:00 Registration will open soon

▶ Flash
GO TO RACE

Bora Experience 2021
Visit the Adriatic Sea for Bora Experience 2021.
Bora winds are feared by local sailors and tend to blow most strongly during the winter months, reaching record speeds above 200 km/h (125 mph). In our virtual Seascape 18 we fear not, and you are invited to race from Venice to Dubrovnik, navigating between the islands along the Croatian coast.
Race #1448
INFO by brainaid.de
Seascape 18 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: SYC
Race starts: Feb 27th 16:00 Registration Open!

▶ Flash
GO TO RACE

New Hebrides Slalom 2021
Welcome… back to the carved-out coastal backdrop of New Caledonia’s opencast nickel mines, for a quick getaway in elegant Italia 14.98's to the islands of the Coral Sea across the Loyaute Basin and on via a mazy zig-zag north to a finish line in exotic Vanuatu's Big Bay. Only 578nm; enjoy!
Race #1425
INFOby brainaid.de
Italia 14.98 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking:
SYQ1 - SYCCH - SUPSOL - SYC
RACE CLOSE: Thursday,
March 4 at 2300 UTC.
Race starts: Feb 23rd 18:00 Registration Closed

▶ Flash
GO TO RACE

Aland Sea TIMED Race 2021
Norrtalje Segelsallskap, 70km NE of Stockholm was founded in 1920, and time was when the society’s season opened with a challenging offshore race from the club line off Flaten island at the mouth of the long and narrow Norrtaljeviken, out onto a triangular course around the Aland Sea, to finish at Simpnas slightly to the north on Bjorko island - some 78nm in total. A fine race that SOL, being from these parts, ran annually up until 2013. Last run in autumn 2018, we return here to race the course again in the form a TIMED RUN in our flashy Club Swan 50s.
RE-REGISTER HERE to race again after finishing a run.
Race #1444
INFO by brainaid.de
Club Swan 50 Particulars
WX Updates:
0430 / 1030 / 1630 / 2230
RANKING:
TRQ1 - TRCH - SUPSOL - SYC
RACE CLOSE: Sunday, 28 February at 23:00 UTC
Race starts: Feb 15th 12:00 Registration Open!

▶ Flash
GO TO RACE

CCA Delivery Cruise 1 2021 - Sandwich MA to Halifax NS

The Cruising Club of America invites you to join them on a (virtual) delivery cruise starting from Sandwich, Massachusetts, the oldest town on Cape Cod in the USA to Halifax, Nova Scotia, Canada, some 354nm away. Once we clear the tip of Cape Cod at Race Point our rhumb line course will be 70 deg T for 225nm across the Gulf of Maine to Cape Sable NS, so the best delivery departure window for sparing the crew and gear pounding into a northeast winter gale across Browns Bank will likely be following a frontal passage with strong favorable westerly winds. You may choose one of two boats, both tailored for cruising and new to Sailonline's boathouse, so flip a coin, study their Particulars sheets and make ready! You may start at any time after 1900utc on 8 February 2021 and you must arrive in Halifax by 4 March at 2300utc.
Race #1417
INFO by brainaid.de
Santa Cruise 52 PARTICULARS
Passport Cruise 40 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
RANKING: NONE
Race starts: Feb 08th 19:00 Registration Open!

▶ Flash
GO TO RACE

Haifa to Sao Vicente - 2021 ESRW - Leg 1
Welcome to bonknhoot’s alternative round the world race, there where it is wide, in six legs, following the setting sun – the ESRW Equatorial Sailonline Round the World Race; equatorial to differentiate it from more traditional antarctical circumnavigations. Expect then to cross the equator frequently, although on this 3500nm first leg from Haifa to the Cape Verdes in Ker 40s you should probably stay north of it. Being a proper ocean race, there are no intermediate waypoints, but please try to leave Tangiers to port anyway.
Race #1427
INFO by brainaid.de
Ker 40 PARTICULARS
WX Updates:
0430 / 1030 / 1630 / 2230
Ranking: ESRW - SYC
RACE CLOSE: Thursday,
March 4 at 2300 UTC.
Race starts: Feb 05th 16:00 Registration Closed

▶ Flash
GO TO RACE

Go to race archive

SYC Ranking

  1. Sailonline Yacht Club Member WRmirekd
  2. Sailonline Yacht Club Member bonknhoot
  3. Sailonline Yacht Club Member rumskib
  4. Sailonline Yacht Club Member NagaJolokia
  5. Sailonline Yacht Club Member rafa
  6. Sailonline Yacht Club Member FreyjaUSA
  7. Sailonline Yacht Club Member Vida_Maldita
  8. Sailonline Yacht Club Member Sax747
  9. Sailonline Yacht Club Member Zorba777
  10. Sailonline Yacht Club Member Kipper1258

View full list

Series

Mobile Client

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

The mobile client