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Old 16-02-2010, 18:20   #16
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I don't undersatnd the answers that mention time. If you have to that you have to go that way. if you don't then you mustn't need to get the any place specific, so what does time have to do with as you must have lots of time.

Me, I don't care what point of sail I'm on. Where just go for a sail and not going anywhere specific will change points just because.
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Old 16-02-2010, 19:29   #17
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In cruising you are generally going somewhere specific rather than just wandering around a river or bay in benign conditions. There is a reason beating to weather is called "crashing and bashing." In the average 2 meter+ (5-10 ft) seas and 20 knots of wind you are actually encountering a relative wind across the deck of 20 knots plus your boat speed whereas downwind your apparent wind over the deck is the wind speed minus your boat speed.
- - As mentioned doing this for days is not fun and it is even not fun for part of a day. You are trying to get somewhere and if you reduce speed you end up not getting there which is not the point of cruising.
-- In the normal seas in the Tropics you need to keep some sail up to stabilize the boat from rolling rail to rail as you climb and descent over each wave and swell which means falling off enough to keep the sail filled as you power ahead with the iron genny. Depending upon the boat this can double or more the distance you have to go to get to your intended next destination.
- - Cat's have a particularly hard time as when they try to motor sail into the wind and waves and end up pitching (hobby-horsing) and their underdeck impacts the waves/swells. Mono's bury the bow and the ocean comes crashing back into the cockpit. Not a fun time after the first few times..
- - On the few well chosen "mild" days of waves around or under a meter going to weather is a fun experience - but that does not happen often in the Trade Winds belt.
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Old 16-02-2010, 19:41   #18
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Surely you understand that one can't head directly into the wind so I guess I am not sure what you don't understand. I found an example that might illustrate "time made good" to windward by sailing off a few points in another's words and will copy it here.
"Applied to beating against the wind the same calculations can be made as follows. Let's say that at 4 points or 45* to the wind your speed is 2.5 kts, but by sailing at 5 points or 56* to the wind your speed is four kts. The VMG (velocity made good) for the 4 point course is 1.8 kts (cosine of 45* c=.7071 X 2.5 = 1.8). The VMG for the 5 point course is 2.2 kts ( 5 pts = c= .5556 X 4kts = 2.2). a 22% increase in speed!"
from 'Coastwise and Offshore Cruising Wrinkles' by Thomas E Colvin.

I hope that helps and doesn't confuse. It is the same principal behind the more common "tacking" downwind to increase time made good toward a leward mark.
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Old 17-02-2010, 04:22   #19
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ConradG:
Your comments are both rules for sailing Nonsuches. They don't really point well and running directly downwind is not recommended. The boat is fairly fast sailing a bit off the wind while beating and even faster when sailing on a broad reach...often surfing over 8 knots. I'm impressed with my boat as it does sail well. I do recall sailing Lasers that had a habit of "death rolling" going directly down wind. Made for some very impressive wipe-outs. Probably a good idea to avoid with a 30' boat.
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Old 17-02-2010, 06:34   #20
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Huh? What has ""time made good" to windward" got to do with cruising? There are only two things we care about _ SOG = Speed Over Ground and Time to Destination. Remember you are traveling in a medium that is also moving (currents) and you can have a great boat speed and lousy ground speed. When trying to get to the next sheltered harbor you can fall off the wind, have a great "speed" and end up doubling your time to destination whereas pinching up to the highest possible to keep wind in the sails and motor-sailing with a reduced boat speed will get you to the destination in half the time or so.
- - The falling off to gain boat speed (and SOG) is an important formula to know so you can determine where the point of diminishing returns happens and then just turn back into the wind and "crash and bash" your way to your destination.
- - GPS's information is great but unfortunately it does not know about set and drift so maybe we are getting a little sloppy with our sailing terminology these days.
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Old 17-02-2010, 07:07   #21
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osirissail, I am imagining, if we are beating, that our destination is in fact to windward. I am in full agreement that sailing close to the wind can be a beating and am suggesting that sailing off a few points can not only make it more comfortable but can, in certain instances, get you there as quickly (or even quicker). It is based on the fact that your speed over ground, even though not as direct to your mark (destination) is increased by doing so enough to overcome the longer distance traveled. If your destination is to windward then you do care about the time made good to windward. And for some of us, the comfort, wear and tear on boat and crew. I am unclear on your reference to gps terminoligy or it's implications to any of what we are talking about. When Tom Colvin uses the terminology "VMG to windward" he is not talking about anything gps in specific but the the speed and time toward the destination (that is to windward), not the speed over the ground on the boats path directly as a reach or broad reach wouldn't help you get to your destination but infact take you the wrong direction, although it certainly would increase your SOG.
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Old 17-02-2010, 21:00   #22
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Quote:
Originally Posted by ConradG View Post
. . . I am unclear on your reference to gps terminoligy or it's implications to any of what we are talking about. When Tom Colvin uses the terminology "VMG to windward" he is not talking about anything gps in specific but the the speed and time toward the destination (that is to windward), not the speed over the ground on the boats path directly as a reach or broad reach wouldn't help you get to your destination but infact take you the wrong direction, although it certainly would increase your SOG.
Huh - again! Prior to GPS (and Loran) we had only the "speed" of the boat through the water. Our knotlog instruments and their little paddlewheels displayed this information nicely. A five knot boat speed into a 3 kt current and we were barely moving over the ground.We had to do fancy calculations to determine set and drift and then resolve our speed over the ground (sea floor) to figure when we were going to get to our destination. Fall off into a contrary current and although your boat speed increases your "ground speed" can decrease near to zero and on occasion I have seen negative speed of the ground.
- - With GPS(/Loran) we were able to directly read the speed over ground along our course and also if a destination way point was entered the "speed made good" to the waypoint. If you do the geometry equations it becomes apparent that falling off to increase boat speed and/or track speed can help get you to your destination quicker - until - your amount of falling off drops your speed made good to the waypoint to a value below what you could maintain by heading directly to the waypoint. With a good GPS or navigation program you can watch both numbers and decide how much falling off is advantageous.
- - One problem with GPS is that some manufacturers use different terminology for these concepts which can get confusing if a discussion is being held and the terminology does not match.
- - An additional factor in actual ocean sailing is that wave patterns do not always follow the wind patterns and sometimes falling off gives a worse ride than slogging directly towards your waypoint. Add in the various characteristics of sailboat shape and rigging and one boat will slice nicely through the waves while the other boat will rock and roll more than plowing straight to the waypoint.
- - Bottom line, there still is a lot of "art of sailing" left and each sailor has to apply the techniques which work best for his vessel. In cruising the common objective is to get to the destination as safely and quickly as possible - especially before the Tiki bar closes.
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Old 17-02-2010, 22:30   #23
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I'm confused... What is being said here?? Is it:

If you cannot sail directly to your destination (downwind or upwind), then VMG is an important factor in determining your progress toward that destination.

and that:

When closehauled, VMG can sometimes be increased by not pointing so high.

If so, I'm in full agreement
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Old 18-02-2010, 06:20   #24
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Yes! Well put. But falling off too much can result in increasing the time to get to your destination.

- - Cruising is a time limited situation as weather patterns, swells, and arrival time (you really do not want to enter a new and strange harbor at night) all are significant factors in the journey. "Weather windows" become a well worn term amongst cruisers working their way around the world.
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Old 18-02-2010, 15:46   #25
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No gps is needed to know that "footing" can be advantageous. Watch two boats in a race, one that is pinching and the other that reaches the windward mark first but sails a few points further off the wind. Gps was a novelty when many of us learned to sail and, I believe, when the piece I quoted by Tom Colvin, naval architect, was written. The best way to determine how your own boat does in certain conditions is by careful study of you logs with keen observation. Using the formulas that I quoted will give you an idea of what is best for a given instance by observations of angle and speed while you're doing it if you are really interested. However, as comfort is what you may be seeking, know that bearing off a bit isn't nescessarily detrimental to your time reaching your destination.
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Old 18-02-2010, 21:58   #26
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Quote:
Originally Posted by ConradG View Post
No gps is needed to know that "footing" can be advantageous. Watch two boats in a race, one that is pinching and the other that reaches the windward mark first but sails a few points further off the wind. Gps was a novelty when many of us learned to sail and, I believe, when the piece I quoted by Tom Colvin, naval architect, was written. The best way to determine how your own boat does in certain conditions is by careful study of you logs with keen observation. Using the formulas that I quoted will give you an idea of what is best for a given instance by observations of angle and speed while you're doing it if you are really interested.
hmmm ... sort of agree... and in bygone days I would have agreed that going fast was an 'art' or perhaps a craft that needed time to be learned.

However, the world has turned and there are now instruments that can give you the relevant information instantly and far more accurately by simply pressing a button.

We do have the option not to go down this avenue. There is far more satisfaction in 'feeling' what needs to happen on the boat than being told what to do by a digital readout.

When I race, I use the instruments because that is the best way to increase speed to a particular destination. When I'm cruising, my aim is to get maximum enjoyment out of the sail - speed is secondary - instruments are secondary.

Horses for courses
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Old 19-02-2010, 06:27   #27
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Yes, what instruments you use to determine what is going on doesn't matter in the least unless by using an instrument you loose track of what you are trying to determine...
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Old 19-02-2010, 07:17   #28
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I've always enjoyed upwind work, that's where the race is won.

A few things:
Set the boat up so it's balanced. Give it enough power so it stands up and drives but don't overpower the boat.

In waves twist off the sails and let the boat sail a bit freer, in flat water the leech can be closed and you can go for point. A tight mainsail leech will give you more upwash, more point, just don't kill it.

When sailing distance sail to shift. If you have access to your polars you can calculate the best course to sail, there is a VMC that is optimum.

Sailing upwind doesn't have to be hard work or uncomfortable and you certainly learn more about balance and trim by doing weather work then any other point of sail.

Here is a good primer for upwind work. Sailing in Shifty Wind

Its not a wind indicator, it points to where I'm going.

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Old 19-02-2010, 07:24   #29
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Quote:
Originally Posted by bewitched View Post
I'm confused... What is being said here?? Is it:

If you cannot sail directly to your destination (downwind or upwind), then VMG is an important factor in determining your progress toward that destination.

and that:

When closehauled, VMG can sometimes be increased by not pointing so high.

If so, I'm in full agreement

I think that there is a third point also being discussed.

If you are willing to sacrifice a little time for a lot of comfort, then foot off just a little from the heading for best VMG. But not too much or you will lose a lot of time.
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Old 19-02-2010, 08:04   #30
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It is interesting to hear the differences in strategy in this thread. It seems that the geographical location you are sailing in greatly affects what is most appropriate. Most of my sailing opportunities occur on Puget Sound. On any point of sail, the prevailing wind direction verses current velocity determines what is best. Frequently we want to sail but must arrive at a certain location in point of time to optimize our progress against the current. VMG on the gps often reminds me that the fun is over and its time to motor.
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