New Posts New Posts RSS Feed: LEE BOW EFFECT
  FAQ FAQ  Forum Search   Register Register  Login Login

LEE BOW EFFECT
 Post Reply Post Reply Page  <1 56789 22>
Author
  Share Topic Share Topic  Topic Search Topic Search  Topic Options Topic Options
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 Topic: LEE BOW EFFECT
    Posted: 19 Oct 11 at 12:44pm
I made a start on some of the illustrations last night, got myself an iPad app, but it takes ages and there are so many bloody variables, I feel a bit silly doing it really as I'm sure it must have been done before by sailing minds far more experienced in boats than me, I'm sure somewhere there must be a book on the subject.

It's a big deal, or it used to be. I did the basic components in a rough sketch for that sea monkey girl, which helps the understanding I guess, I'll bung what I've got up here in a minute, but to really illustrate what happens at various speeds would take hours..

My old notes and records got lost in a house move twenty years ago, which is a shame, because I'd documented the tide variations in the various courses and venues I'd sailed during my fifteen minutes of fame and glory and I had done it precisely because my memory was never totally reliable, one coastal tide bend easily gets confused with another.. Not for one moment would any of those venues be anything like the way they were then as the bottom shifts all the time, but the examples would have helped illustrate the point.
https://www.ease-distribution.com/
Back to Top
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 Posted: 19 Oct 11 at 12:26pm
GRF -I don't want to get involved in a slanging match but I just like to deal with the points that you have raised. 
First, I am not a " full time coach", I race dinghies most weekends and spend some time helping the young kids at the club. Where I sail is very tidal with 3 1/2 knots on springs, so I do have a lot of practical experience racing in strong tides.  I have also done, in my youth, a lot of international dinghy events so I have a depth of knowledge on dinghy racing tactics. 

My position on this is that until 1982 I fully believed in the Lee Bow effect and could vouch for numerous situations where it worked in my favour. In a discussion with one of my competitors I was astounded when he stated that there was no lee bow effect. He then explained it to me and he convinced me that I had been wrong, ( that sailor was Steve Goacher). I now have a simple explanation of the effect (or lack of it!) that I do for anyone that is confused on the matter! So if anyone wants I can do this on this thread, (but I suspect it has been done to death anyway)

PS I even remember racing against you in IMCO in the 80's
Back to Top
bert View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 23 Apr 05
Location: norwich usually
Online Status: Offline
Posts: 584 		Post Options Post Options   Quote bert Quote  Post ReplyReply Direct Link To This Post Posted: 19 Oct 11 at 11:54am
Originally posted by bert

I for one look forward the "drawings and try and remember all the tactical scenarios I used to illustrate and what to do in various circumstances to even the odds in your favour, but it won't get done overnight."
& thank you GRF if you can do for me / us -- no piss take I would geninely like to understand this better.
 
Would you consider doing this,If you could find the tactial stuff & illustions that would be great.
This back & forth posting is just confusing & in danger of becoming a worthless thread when it could be a great benifit to a lot of people if it was explained well.
 
Thank you 
 
bert
Phantom 1181
AC-227 IC 304
blaze / halo 586


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: 19 Oct 11 at 10:49am
Coaches like you are why the status quo remains the same and so many youngsters never get anywhere is all I can say to that.

The coach that gave me that ten minute victory all those years ago told his team of youngsters exactly the same thing.

Tidal strategy is complicated, anyone who thinks it's simple just doesn't know enough to advise others, let alone write about it, interesting other than a few naysaying forum posters I can't find any supporting evidence to back David Perry, but all I find is lots of people quoting him. Whereas there is a great deal of supporting evidence, including my own experience, that supports my view.

So best you read a bit more, go sail in tide a bit more and find out the truth for yourself before dissuading young minds of the importance of learning about when and how 'lee bow effect' can be beneficial.




Edited by G.R.F. - 19 Oct 11 at 10:59am
https://www.ease-distribution.com/
Back to Top
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 Posted: 19 Oct 11 at 10:30am
Yes I have just seen the bit in the latest Y&Y that mentions pinching to get the beneficial "lee bow" effect. Its a bit unfortunate that so callled experts, who should know better, are still harping on about this that I thought had be debunked 20 years ago! I help out with the young kids at the club and I try to explain to them that tidal strategy is really quite simple ( if it against you get into weaker tide, and if it is with you get into the stronger tide) -If you throw into the mix the "magical" properties of the lee bow effect it all becomes really complicated, and sets them off in all the wrong direction. 
I think that all the offenders (and GRF and John Emmett should know better), should be taken to one side and have it explained to them with the aid of beer mats and a table cloth. So that we can finally lay this myth to rest! 
Back to Top
sargesail View Drop Down
Really should get out more
Really should get out more
Avatar

Joined: 14 Jan 06
Location: United Kingdom
Online Status: Offline
Posts: 1459 		Post Options Post Options   Quote sargesail Quote  Post ReplyReply Direct Link To This Post Posted: 18 Oct 11 at 8:29pm
Being faster means the relative gains are smaller that's all.  2 knot tide, 4 knot boatspeed v 2 knot tide 10 knot boatspeed.  Simple.
Back to Top
fudheid View Drop Down
Far too distracted from work
Far too distracted from work
Avatar

Joined: 21 Apr 11
Location: 51.53 N 01.28 E
Online Status: Offline
Posts: 241 		Post Options Post Options   Quote fudheid Quote  Post ReplyReply Direct Link To This Post Posted: 18 Oct 11 at 4:24pm
Originally posted by G.R.F.

 
As to your statement it should read, if two boats are sailing into adverse current with the tide on the nose or slightly to the weather bow, and one managed to point high enough to get the tide on the lee bow, then what would be the outcome... The answer to that question very much depends on the type of boat in that scenario as well, to answer that, one would have to have a different answer for different classes of boat.


Surely if the 'lee bow effect' works and the two boats are the same class whether skiff, windsurf, yacht, whatever the same hull. then the 'out come' would be the same.
 that is to say if you think lee bow works one of the boats will be clear ahead ......the boat with tidal lee bow?
If it was you which boat would you be? and why? is there a difference purely down to the tide?
Back to Top
fudheid View Drop Down
Far too distracted from work
Far too distracted from work
Avatar

Joined: 21 Apr 11
Location: 51.53 N 01.28 E
Online Status: Offline
Posts: 241 		Post Options Post Options   Quote fudheid Quote  Post ReplyReply Direct Link To This Post Posted: 18 Oct 11 at 3:59pm
after 15 pages beginning to falter on what is known and not known, i feel a bit rumsfield!
Have just read in latest edition of Y and Y on page 32 how to take advantage of the lee bow effect! If it doesn't work why are they promoting dodgy theories is the world flat? looks flat from my window Wink
Back to Top
2547 View Drop Down
Really should get out more
Really should get out more


Joined: 11 Aug 11
Online Status: Offline
Posts: 1151 		Post Options Post Options   Quote 2547 Quote  Post ReplyReply Direct Link To This Post Posted: 18 Oct 11 at 9:43am
Originally posted by G.R.F.

Originally posted by seamonkey

 

Draw a quick sketch of the forces that show this and post it GRP ...

Yeah ok maybe later..


I await with interest ...
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: 18 Oct 11 at 9:38am
Originally posted by seamonkey

 

Draw a quick sketch of the forces that show this and post it GRP ...

Yeah ok maybe later..

Originally posted by G.R.F.

So ignore the planing thing, it's a red herring, tidal stuff is really the province of sub planing when we're looking for more power or at the very least not wanting to cede what we already have.


Why would you think the mode of sailing changes the impact of tide?
[/QUOTE]

Because in planing mode there is no shortage of power, tide only becomes a serious issue when you need supplemental power, and in planing mode as a percentage of exposure the time period is so much less, so consideration to it's importance needs to be less, other factors become more important.
https://www.ease-distribution.com/
Back to Top
 Post Reply Post Reply Page  <1 56789 22>

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