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Debunking Dodgy Sailing Theories |
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JohnW
Really should get out more Joined: 17 Jul 07 Location: United Kingdom Online Status: Offline Posts: 552 |
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Topic: Debunking Dodgy Sailing Theories Posted: 21 Oct 11 at 11:32am |
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No, not always the "best" way. Agree wide in tight out has tactical advantages, but in the absence of other nearby boats an apex turn is faster by around a boat length (which in my book is generally better when racing). The myth is that being further "upwind" is better, in reality the apex turn puts you ahead of where you would have been if you had done the "racing turn". You may be slightly to leeward of the exit line from the mark, but because you sailed a shorter distance you are in fact ahead by about a boat length. |
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Isis
Really should get out more Joined: 01 Sep 05 Online Status: Offline Posts: 2753 |
Post Options Quote Reply Posted: 21 Oct 11 at 11:36am | ||
When a significant proportion of the displacement is supported by dynamic lift. What qualifies as significant? thats the tricky bit. |
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Beast of Bodmin
Newbie Joined: 20 Mar 06 Location: United Kingdom Online Status: Offline Posts: 17 |
Post Options Quote Reply Posted: 21 Oct 11 at 11:38am | ||
Was recently told that with only 5 knots at sea level you can regularly see 30 knots at mast tip ( 30ft for us ) .Came from a very reliable source but doesn't seem possible or apparent to me . What's your expereince ?
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rogue
Really should get out more Joined: 04 Dec 08 Location: United Kingdom Online Status: Offline Posts: 978 |
Post Options Quote Reply Posted: 21 Oct 11 at 11:47am | ||
it's the thing that means the same thing as planning on a sailing forum, however it is spelt correctly. |
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RS400atC
Really should get out more Joined: 04 Dec 08 Online Status: Offline Posts: 3011 |
Post Options Quote Reply Posted: 21 Oct 11 at 12:12pm | ||
Depends what you mean by 'sea level'. 10cm? 1m? If you measure at three metres and ten metres, there is usually a measurable difference, 20% is sometimes used as a rule of thumb, but it varies I believe. The true wind direction also varies! Air close to the ground spirals into the low pressure more steeply than faster moving air high up. But in reality, these big picture simplifications are often obscured by local effects. |
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fudheid
Far too distracted from work Joined: 21 Apr 11 Location: 51.53 N 01.28 E Online Status: Offline Posts: 241 |
Post Options Quote Reply Posted: 21 Oct 11 at 1:50pm | ||
Don't you just do the apex turn so you come out next to the mark??
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JohnW
Really should get out more Joined: 17 Jul 07 Location: United Kingdom Online Status: Offline Posts: 552 |
Post Options Quote Reply Posted: 21 Oct 11 at 2:31pm | ||
If you come out next to the mark it is not an Apex turn. I was going to draw a diagram, but this article explains it better than I could: |
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I luv Wight
Really should get out more Joined: 28 Jan 05 Location: United Kingdom Online Status: Offline Posts: 628 |
Post Options Quote Reply Posted: 21 Oct 11 at 10:29pm | ||
This is definitely planing, ( ie exceeding the hull speed of a foot = 1.43 knots according to some theories) http://youtu.be/IlruXNU9i6k |
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Guests
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Post Options Quote Reply Posted: 21 Oct 11 at 10:48pm | ||
No no no no no. Planing has nothing to do with exceeding a particular speed.
I can't see the video at the moment, hope it's a good one! Edited by Peaky - 21 Oct 11 at 10:51pm |
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I luv Wight
Really should get out more Joined: 28 Jan 05 Location: United Kingdom Online Status: Offline Posts: 628 |
Post Options Quote Reply Posted: 21 Oct 11 at 11:04pm | ||
Err... see the title of the thread! |
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