Pointing higher on one tack

Dyflin

Dyflin

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We were out in some quite strong conditions last night and had the full main up (seas a bit lumpy to scramble up on coachroof) and had the furling genoa at various lengths (trying to achieve good shape and speed vs amount of cloth out). We have only recently started going out in stronger winds (F5/6) as our experience increases.

But we seemed to be able to point higher on starboard tack than port tack and I wondered if this was due to the standing rigging tuning? i.e. is the mast slightly over to one side? I plan to measure the distance from masthead to deck at the shrouds to determine this, but am I barking up the wrong tree?
 
This sort of thing is quite common. The most likely explanation is wind shear, the difference between wind direction lower down and higher up. The wind is 'backed' closer to the ground or water surface, so the wind a little higher up is coming from a direction more 'to the right' as you face the wind (in the N hemisphere), allowing you to point a little higher on starboard.
No doubt someone will be along shortly to offer an entirely different explanation.
 
Mine "appears" to do the same, but this is becuase I haven't gone to the bother of properly calibrating the wind instrument( going round in 3 large circles after getting to the right point in the "menu" and then pressing 2 buttons for the duration of the 3 circuits has always been a step too far), hence I appear to be pointing 8 degrees higher on one tack but really the wind instrument is misreading by 4 degrees !
 
The movement of the tide may also affect you more on one tack than the other, even in semi-enclosed lakes backing onto the ocean.
 
I wondered about this as well.

In this image:
hw1.gif


It shows the tidal streams for Dublin bay at HW+1. We were in the approximate position of the bottom right arrow at this time. This also corresponded roughly to the wind direction (a little more NNW maybe but roughly right). I downloaded the track from the gps this morning and was surprised by how hard we struggled to make any ground to the north when on port tack in this area.
 
Firstly, how are you determining this ?
If the dubios wind indicator, then it is possibly out of alignment, adjustment, seen it Many many times.
If you have a good windex, site up the mast, if this is aligned, then use that - much better than the electronic gizmo lol.
If all that is absoltely fine, then look elsewhere, but try that first.
Again, a very common assumption by many and often wrong.
 
We have no windex at the moment as it fell off last winter. We use the ensign and telltales while we're out and then the gps track uploaded to chart software for Après-sail info.
 
It could be any number of things, as others have pointed out. I've never found a boat that doesn't have one favoured tack, even if only a very slight bias.
I'm a bit concerned that you felt it was too rough to reef. This is a pretty dangerous mind-set. I once called for the storm jib to be told by my crew that it was too rough and we should wait until the wind dropped! You might want to practice reefing so that when the need arises it's second nature and not something to dread.
 
The Leisure 23 has a ridiculously small main and and a very awkward coachroof with effectively zero side decks. The seas in the area where we thought about it were particularly rough (up to two metres) as it is an area of overfalls.

I have been forward in similar conditions and it's not a pleasant experience at all. I made the call not to put skipper or crew at risk as we could simply return to the shelter of lee behind the islands in the south end of the bay and reef there. Once clear of the overfalls life seemed to return to normal and we were fine again.

I take your point, but I think we made the right decision at the time.
 
Hi sir
Fit another windex, you are getting a tad too technical if you are using a dumped gps track etc. the boat should point equally, or there abouts using windex, on a dumped track the effects of current tide etc are there with no way of knowing realistically.
Start simple, the post on when to reef is valid, but I know exactly what you mean, we have all bin there so to speak.

There are so many external variables, but the humble windex works well, far better than the ensign etc.

Hope you get it sorted and happy sailing.
Joe /forums/images/graemlins/smile.gif
 
It also sometimes happens that the waves are not lined up with the wind direction and you are forced to sail a bit freer on one tack.
 
I haven't got my book to hand, but I think that motoring round in circles calibrates the linearity of the display but that there is a separate calibration to centre it which involves motoring directly into the wind. Like you, I've never got round to doing it.
 
I have been trying to recruit a suitbly sized "deck monkey" to send up the mast, but so far they all run a mile at the suggestion!

Btw, the Irish have a great saying that I've always adhered to
"Please don't call me Sir, I work for a living!" /forums/images/graemlins/wink.gif
 
I had exactly the same on my previous boat, a Jaguar 27. When ashore one winter I noticed the keel was not vertical by about 3-4º - and from then on I always assumed this was the reason.
 
In bays the seas dont al;lways run in line with the wind as they curl around the head lands .Possibly the effect of the sea pushing you more from the beam on port tack was increasing your leeway?

Before you start altering the rigging you need to check it on a reasonably flat sea.

Measuring your track across the ground is no help as even a weak tide will affect the angles.If no wind instruments (Personally I think they are a waste of time on a cruising boat)then use your tell tales and the compass.Point her head to wind note the heading then pay off uintil sailing close hauled on each tack noting the compass heading again.If she is tacking through about 45° each side of the wind thats about as good as you will get.
 
I generally go dutch rather than speak it /forums/images/graemlins/grin.gif

Although, I know three phrases in Dutch;
Hello,
two beers if you please
Bye.

You'd know we only got a short time for shore leave in Den Helder /forums/images/graemlins/laugh.gif
 
Apart from all the good advice that has been written above, I suggest that, after checking your rigging for symmetry, do some more observations when the genoa is <u>completely unfurled</u>. Having it partly rolled will throw a bias on one tack, enough to make the set - and the efficiency - markedly different from the opposite tack. The flow over the leading edge will be smoother on the convex side according to whether the sail is rolled to port or to starboard.
At the end of the day, like all things on a boat, reach a compromise and learn to live with it. /forums/images/graemlins/wink.gif
 
I have set up my leisure 23 rig very carefully to be vertical, with the right tension, etc. It sails better on one tack, rather than the other, especially in stronger winds. I know it's not the rig, so I put it down to roller reefing/tidal currents/wave direction/the idiot on the helm/pixies. Maybe not the last one....
 
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