Sailing in tide..quiz.

Originally posted by Dougaldog I'm sorry to spoil the earlier comments about how the line was laid, but any RO worth the title takes his wind readings from a 'free floating' boat and not one that is moored. At the OK's a fortnight okay, sailed over the highest springs of the year, we delayed final position whilst taking wind readings when drifting. Once we anchored the Committee Boat the course looked 'orrible and skewed - but as soon as the boats came out to start sailing and you could see them close hauled on both tacks, the beat looked spot on. D

The bias is very real. It won't feel like a shift though, it will just feel like committee boat is favoured. 

Edited by mozzy - 03 Oct 17 at 9:13pm

OK I've now given this considerable thought,

First I'm going to concede in your circumstance (If I'm right you're quite a handy RS200 jockey with at least one championship win to your tally and you're a Hayling man, so not entirely without tidal credentials) which in that particular boat (In which I've only had very limited experience, but enough to tell me that going too high would slow the boat significantly more than any tidal gain would exacerbate, which isn't the case with an 18 kilo board, or even a 50 kilo single hander, so forget the pinching it's irrelevant to you and you'd never have experienced it.

But,

Second I'm going to call you on your assumptions regarding the tidal lift off that line and in this instance I'm going to quote back at you the conveyor belt assumption which will lift all the boats on starboard off the line, but not in the same way an actual wind shift would, i.e the relation of the boat sailing angles will not alter. They'll still point as they would in relation to the true wind angle but the inter boat relationship angle would not change as it would in a wind shift, so a faster boat off the Port end could still make enough ground to tack across slower starboard boats from the starboard end. The vector they all make good however would follow your assumptions.

Edited by iGRF - 03 Oct 17 at 4:57pm

Originally posted by mozzy Originally posted by iGRF one of the other reasons for choosing the port end, is the liability that going right will cause possible overstand scenarios at the windward mark. Just seen this. So your answer to over standing the windward mark is to start further left?  How would starting on the left possibly make calling the layline easier?  The answer to that may be, that if you start port end you won't be first to the layline, so you can use the leading boats to judge when you should tack. Not going to win many races that way though!

As I said, it's not a complete scenario, you haven't quantified the line length, nor length of the beat, but assuming it's a big fleet with a long line and say half mile beat, then the left has more options than the right unless you somehow manage to blast clean from the pack off the line which would be very unlikely from the starboard end for all the reasons you cite.

Mainly because the left will over the course of the race become the middle.