If your destination is directly to windward, how much more time to allow...

... and if you are to head south across the channel and the wind is a pure southerly.. then aim to 'lee bow' the tide.

i.e. with the East going tide aim to be on a port tack and the tide will 'lift' you to the east.. Then as the tide turns and becomes west going, aim to tack onto Stbd and the West going tide will again give you another good lift to windward..

Your final Course Over Ground will also then look a lot straighter (and more perpendicular to any shipping lanes).
 
Martin_J said:
... and if you are to head south across the channel and the wind is a pure southerly.. then aim to 'lee bow' the tide.

i.e. with the East going tide aim to be on a port tack and the tide will 'lift' you to the east.. Then as the tide turns and becomes west going, aim to tack onto Stbd and the West going tide will again give you another good lift to windward..

Your final Course Over Ground will also then look a lot straighter (and more perpendicular to any shipping lanes).
Click to expand...

The main thing is usually to get a good forecast and set off on the tack that is going to be headed as the wind shifts, so you are lifted when you tack.
Or if the wind shifts are not predictable, be on the 'making' tack.
 
>If your destination is directly to windward, how much more time to allow...

I just looked at our log for an upwind, up-current (about 1 knot) sail from Curacao to St Lucia. The distance as the crow flies is 320NM and we sailed 480NM tacking all the way. It took 10 days as we had 20 knots of wind and gusting plus waves and quite big swells against us, with lots of solid water (slowing us) flying over the bows and the spray at mizzen boom height. I think the moral of the story is it's unlikely you can get an accurate figure for the time you arrive, we never did and we did a number of upwind passages. It all depends on the sailing conditions conditions and how high they let you point, as you can see from the mileages we were being pushed sideways all the time by the swells, so the pointing was way below what we can do, 50 degrees normally.

On one occasion we crossed 68 degrees west three times being pushed back by un-forecast 10 foot swells and 2 knots of current when leaving Bonaire for the BVI's and put into Puerto Rico until the swells went down.
 
Sailing to windward is a mugs games unless you absolutely have to. Either stay put until the wind changes or choose somewhere else to go. It's a lesson we learnt trying to beat into the wind up the Staits to Gib: all we did on the two attempts we made was to tear the genoa and get grumpy with one another. Better by far to wait it out.
 
haydude said:
This is nice, do you expect us to do your passage plan for you?
Click to expand...

What a stupid comment. I posed a theoretical question (inspired by a real situation) which resulted in an interesting, illuminating, sometimes opiniated but thoroughly civil discussion. Until you chipped in.

Something people need to avoid when participating on forums, as in real world communities, is not to inflict the creepier sides of their personality on others.
 
As a rule of thumb I reckon VMG to windward is roughly half speed over ground, but it depends a lot on the conditions. I don't think motorsailing would help much - if you have the engine on you might as well use it to head directly to the destination.
 
Motor sailing into a headwind can often be more comfortable than motoring directly into the wind and sea. We motorsail at 30 degrees to the true wind at, say, 6 knots and are probably lucky to get near to 45 at a similar speed when sailing.
 
Another question to ask is "how much faster do I need to go if I bear off a bit (to achieve same VMG)?"

Of course it depends on the increase in speed as you bear off but a good rule of thumb at speeds relevant to many cruising boats is: if you bear off by 10 degrees, you need to speed up by at least 1 knot.

COS40 (COS being the trigonometry function on your calculator and 40 being your angle to true wind) x 4 knots = 3 knots VMG
COS50 x 5 knots = 3.2 knots VMG
COS60 x 6 knots = 3 knots VMG

Similarly:
COS40 x 5 knots = 3.8 knots VMG
COS50 x 6 knots = 3.9 knots VMG
COS60 x 7 knots = 3.5 knots VMG

60 degrees to the wind is a lot more comfortable than 40, in many if not most yachts, and you are also less likely to be making as much leeway. And/or, because you have greater momentum at higher speeds, and are hitting waves less directly, less likely to be slowed by the waves. (Pointing at 40 degrees to wind your actual course over ground may be more like 50, at a slower speed, whereas at 60 degrees you may really achieve the 60 degrees at a more sustained speed.)

So when people talk about sailing faster with the sheets cracked off a bit, they are not necessarily wrong.

At slower speeds, in choppy conditions - where hitting short sharp waves may periodically stop the craft altogether, eg a small sailing dinghy tender - heading off might make an even bigger difference:
- COS 40 x 1.5 knots = 1.2 knots VMG
- COS 50 x 2 knots = 1.3 knots VMG
- COS 60 x 3 knots = 1.5 knots VMG (25% faster than 40 degree course)
- COS 70 x 4 knots = 1.4 knots VMG

Ian, Nestaway Boats Ltd
 
>Sailing to windward is a mugs games unless you absolutely have to. Either stay put until the wind changes or choose somewhere else to go.

I agree, but you can't do that in the Caribbean the wind is always from the East, wind reversals only happen in hurricanes. So if you want to visit the ABC's, we did for the excellent diving, then you have no choice but to sail upwind. It's doable but not pleasant. We did about 1,400 NMs upwind and over 10,000NM overall so not much upwind, it's character building ;-)
 
Babylon said:
What a stupid comment. I posed a theoretical question (inspired by a real situation) which resulted in an interesting, illuminating, sometimes opiniated but thoroughly civil discussion. Until you chipped in.

Something people need to avoid when participating on forums, as in real world communities, is not to inflict the creepier sides of their personality on others.
Click to expand...

Asking the question in the first place might suggest to some that you need someone to do the passage plan for you

Don't get the hump at a lighthearted comment-- even if it does highlight some of your possible shortcommings
 
Daydream believer said:
Asking the question in the first place might suggest to some that you need someone to do the passage plan for you

Don't get the hump at a lighthearted comment-- even if it does highlight some of your possible shortcommings
Click to expand...

I didn't ask anyone to do my passage plan for me. I was looking for feedback on and insight into a theoretical question based on a real scenario.

Heydude had nothing to contribute to the thread except an unnecessary and personal jibe. Come to think of it, neither do you...
 
Babylon said:
What a stupid comment. I posed a theoretical question (inspired by a real situation) which resulted in an interesting, illuminating, sometimes opiniated but thoroughly civil discussion. Until you chipped in.

Something people need to avoid when participating on forums, as in real world communities, is not to inflict the creepier sides of their personality on others.
Click to expand...
Stupid comment? Do you really think so? I was the first to reply to your OP and got no response from you; time waster.
Since then I've been watching sensible people trying to respond in sensible ways to what was actually an inane, ill thought out question.
Your OP is probably one of the daftest questions I've ever seen posted on this forum.
 
ArthurJStoatfondler said:
Stupid comment? Do you really think so? I was the first to reply to your OP and got no response from you; time waster.
Since then I've been watching sensible people trying to respond in sensible ways to what was actually an inane, ill thought out question.
Your OP is probably one of the daftest questions I've ever seen posted on this forum.
Click to expand...

Have you had a cup of tea yet?

Maybe you were tired or a bit tipsy or irritated with life generally when you typed this last reply last night, but your post is lazy, unnecessarily rude and untrue.

If you trouble yourself to actually read Post # 8 (my first chance to reply after half a dozen peeps, including yourself, had thought it an interesting enough thread) you will see that I REPLIED IN FULL DETAIL TO YOUR QUESTION!

So, if questions about actual sailing are too "daft" to raise on a sailing forum, what do you think IS a good question to ask?
 
nestawayboats said:
Another question to ask is "how much faster do I need to go if I bear off a bit (to achieve same VMG)?"

Of course it depends on the increase in speed as you bear off but a good rule of thumb at speeds relevant to many cruising boats is: if you bear off by 10 degrees, you need to speed up by at least 1 knot.

COS40 (COS being the trigonometry function on your calculator and 40 being your angle to true wind) x 4 knots = 3 knots VMG
COS50 x 5 knots = 3.2 knots VMG
COS60 x 6 knots = 3 knots VMG

Similarly:
COS40 x 5 knots = 3.8 knots VMG
COS50 x 6 knots = 3.9 knots VMG
COS60 x 7 knots = 3.5 knots VMG

60 degrees to the wind is a lot more comfortable than 40, in many if not most yachts, and you are also less likely to be making as much leeway. And/or, because you have greater momentum at higher speeds, and are hitting waves less directly, less likely to be slowed by the waves. (Pointing at 40 degrees to wind your actual course over ground may be more like 50, at a slower speed, whereas at 60 degrees you may really achieve the 60 degrees at a more sustained speed.)

So when people talk about sailing faster with the sheets cracked off a bit, they are not necessarily wrong.

At slower speeds, in choppy conditions - where hitting short sharp waves may periodically stop the craft altogether, eg a small sailing dinghy tender - heading off might make an even bigger difference:
- COS 40 x 1.5 knots = 1.2 knots VMG
- COS 50 x 2 knots = 1.3 knots VMG
- COS 60 x 3 knots = 1.5 knots VMG (25% faster than 40 degree course)
- COS 70 x 4 knots = 1.4 knots VMG

Ian, Nestaway Boats Ltd
Click to expand...

If one is not confident of doing the crossing in daylight hours and getting to your destination isn't optional, one should factor in an overnight crossing in order to arrive in daylight.

Incidentally I love your 9' clinker dinghy.
 
Sybarite said:
If one is not confident of doing the crossing in daylight hours and getting to your destination isn't optional, one should factor in an overnight crossing in order to arrive in daylight.
.
Click to expand...
Either that or carry a GPS - which I believe can be bought quite cheaply these days :)
 
Babylon said:
So, if questions about actual sailing are too "daft" to raise on a sailing forum, what do you think IS a good question to ask?
Click to expand...

Well put. I thought it was an interesting question and watched too, to see different perspectives to the problem. From my own recent experience making a 140 nm coastal hop - I had planned on the basis of the forecast winds to average 4 kts (conservatively) so leaving in the morning would get me there the following afternoon. Got out of harbour to find light wind coming right from my destination. After 24 hrs of tacking, was only 50 miles into it, with 90 to go. Motor-sailing with the light wind really meant motoring a greater distance, so furled the sails and motored direct until the sea-breeze kicked up in the afternoon, then was able to sail through the second (unplanned) night.
 
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