New Posts New Posts RSS Feed: Strategy in tide??
  FAQ FAQ  Forum Search   Register Register  Login Login

Strategy in tide??

 Post Reply Post Reply Page  123 4>
Author
Oatsandbeans View Drop Down
Far too distracted from work
Far too distracted from work


Joined: 19 Sep 05
Location: United Kingdom
Online Status: Offline
Posts: 382
Post Options Post Options   Quote Oatsandbeans Quote  Post ReplyReply Direct Link To This Post Topic: Strategy in tide??
    Posted: 29 Sep 08 at 1:23pm
I am a bit confused over when starting with a tide running parallel to the
line should you start at the uptide end (all other things being equal) or does
it make no difference as. Most books plump for this (uptide end), but I
suspect that it doesn't make any difference.

Any thoughts??
Back to Top
G.R.F. View Drop Down
Really should get out more
Really should get out more


Joined: 10 Aug 08
Location: United Kingdom
Online Status: Offline
Posts: 4028
Post Options Post Options   Quote G.R.F. Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 2:56pm
Starting in any amount of tide offers the astute tactical tidal sailor
options..

These options rely obviously also on the wind. There is a school of
thought that sailing in tide is like riding an elevator it's the same for
everyone, but in lots of cases it aint.

The lighter the wind, the more the tide has an effect, only yesterday I
watched our commodore go from 1st to last in one tack off the line when
he strayed into a tidal back eddy, and the funny thing, we're a tidal club,
but no-one had even noticed it, yet there it was plain as day described in
darker coloured ripples for all but the partially sited to view.

Again, in danger of turning a post on a thread into a chapter of a tactical
sailing book, as a rough rule of thumb if you can start with the tide
pushing against your lee bow, you will move faster off the line than all
the boats with the tide on their weather bow. Being on Port or Starboard
is obviously the overiding factor, or if you could get a port flyer and have
the tide on your lee bow whilst the fleet head off on starboard with a tidal
weather bow, you would have to do something dramatically wrong not to
beat them to the first mark.

There is also another fundamental point to back this, in the seconds after
the gun, particularly in a big fleet, you can lose tens of places per second,
make an error at the top of the triangle and you maybe lose one or two
places, so another reason to grab any tidal gains early on.

I'll not stray into course bias, but I would be concerned not to over cook a
favorable tide then end up over shooting the buoy allowing boats
previously under you to overtake by pointing high whilst you're having to
free off.

This sort of discussion needs illustrations or a chalk board - I'm available
for lectures
Back to Top
Guest View Drop Down
Newbie
Newbie


Joined: 21 May 04
Location: United Kingdom
Online Status: Offline
Posts: 0
Post Options Post Options   Quote Guest Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:03pm

Makes no difference so other factors dominate.

That is assuming the line is square to the apparent wind not the actual wind as measured on the mored committee boat.

Back to Top
radixon View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 27 Oct 06
Location: United Kingdom
Online Status: Offline
Posts: 2407
Post Options Post Options   Quote radixon Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:34pm

Surely you would start up tide, so when sailing the beat, you will end up drifting slightly with the tide and not have to correct yourself.

Got bored trying to draw a diagram, if you start at the down tide end, you will constantly be batteling tide so may end up drifting further away from the windward mark.

At least starting upwid, you can tack and sail with the tide assisting you if needed.

 

(sorry probably waffling rubbish!)



Edited by radixon
Back to Top
Guest View Drop Down
Newbie
Newbie


Joined: 21 May 04
Location: United Kingdom
Online Status: Offline
Posts: 0
Post Options Post Options   Quote Guest Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:34pm
Originally posted by turnturtle

Originally posted by Guest#260

Makes no difference so other factors dominate.



not sure I agree that it makes no difference Rick, certainly not for slower boats...  but agree other factors do dominate my own decisions in tide, especially off the line.

This is and idealised situation; if the tide is perfectly parallel to a line that is perfectly square to the apparent wind (not actual wind) then it makes no difference.

I refer you to mark Rushall's excellent book Tactics.

What I am calling apparent wind he calls sailing wind and it's the resultant experienced wind which is made up of the actual wind over the land as experienced on the commitee boat and the tide.

If the line is layed square to what the race officer experiences as wind on the committee boat start at the down tide end.

A good race offcier would know this and drop the pin back to compensate for this.

Fig 6.5 on page 72 illustrates this ...

Back to Top
G.R.F. View Drop Down
Really should get out more
Really should get out more


Joined: 10 Aug 08
Location: United Kingdom
Online Status: Offline
Posts: 4028
Post Options Post Options   Quote G.R.F. Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:46pm
Deletes lengthy post.

Is it worth arguing the point?

I suppose it's why there can only ever be one winner..

Back to Top
FireballNeil View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 03 Oct 06
Location: United Kingdom
Online Status: Offline
Posts: 654
Post Options Post Options   Quote FireballNeil Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:53pm

On the topic of tides, can someone tell me the basics of Hayling tide? Ive not been before, I have hardly sailed in tide and Im going this weekend!

Neil

Back to Top
Phil eltringham View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 16 Mar 04
Location: England/Hitchin
Online Status: Offline
Posts: 1105
Post Options Post Options   Quote Phil eltringham Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 3:54pm
This assumes all other things are equal!:  If the tide is at 90 degrees to the wind i'd say start at the right hand end of the line every time.  If its going right to left, starting at the right hand end means you can tack off earlier and get the lee bow up the first half of the beat and hopefully cross the fleet later on.  If its going left to right, need to be carful you don't get pushed onto the committee boat, but you'll start with lee bow on startboard (along with everyone else), but at right hand end, have a better chance of clear air.  I'm probably wrong about this so comments please...
FLAT IS FAST!
Shifts Happen
Back to Top
Guest View Drop Down
Newbie
Newbie


Joined: 21 May 04
Location: United Kingdom
Online Status: Offline
Posts: 0
Post Options Post Options   Quote Guest Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 4:09pm

Originally posted by turnturtle

 .... other factors have significantly more input into my decisions than tide at the start.

At Draycote I am sure that is always the case ... but in some instances tide could be the most important factor at the start.

I think many people don't understand the difference between the sailing wind the competitors experience and the true wind the race officer experiences.

Without understanding this I think people will never be able to win at a tidal venue.

Back to Top
Guest View Drop Down
Newbie
Newbie


Joined: 21 May 04
Location: United Kingdom
Online Status: Offline
Posts: 0
Post Options Post Options   Quote Guest Quote  Post ReplyReply Direct Link To This Post Posted: 29 Sep 08 at 4:58pm
Originally posted by turnturtle

Originally posted by Guest#260

Originally posted by turnturtle

 .... other factors have significantly more input into my decisions than tide at the start.

At Draycote I am sure that is always the case ...

I dunno, I find my one and only pint of driving lager ebbs far too quickly on a wednesday night....

interesting points re apparent wind, is there a documented resource online for this phenomenon?  (I might get salty next year, so interested in finding out...)

All covered in Mark's Book.

http://www.rushall.net/Shop.htm

Back to Top
 Post Reply Post Reply Page  123 4>

Forum Jump Forum Permissions View Drop Down

Bulletin Board Software by Web Wiz Forums® version 9.665y
Copyright ©2001-2010 Web Wiz
Change your personal settings, or read our privacy policy