sailing closer than 90 degrees....

[groundhog]

Hello...
So I post to my boat owners forum about a furler, and mention that I can point quite well now that I have the furler.

This topic has come up before as I had judged my boats pointing ability using the windvane alone which has inaccuracies with apparent wind, leeway etc.

So I was repremanded and told to go use my GPS.

My comment before was that I just have experienced that the relative comparison between my old hank on headsail and the new 150 furled one are similar and that with the wind vane sneaking inside the 90 degree cone of .... whatever...no go.

So I came back in and mentioned that last summer, i did in fact use my GPS with the display trails enabled. I went as close to the wind as I could for awhile, then tacked. Then went the opposite way close to the wind and then checked the angle that I had drawn with my GPS. Sure enough, it was less than ninety degrees.

Now theoretically, i guess, i shouldn't have been able to do this? They are all laughing at the retarded man on my home forum. Great fun they are having....

There must be an explanation for what I did.
Any ideas?

[CalebD]

Dude,
Furlers are great things to have on your boat. They come with a cost though.
The leading edge of any furling mechanism is an impediment to the angle the wind can come in at which is why hank on sails for a jib usually provide a better angle of attack to the wind.
Your main sail may have a mast at the luff that is much wider then your furler but it all matters.
Hank on sails for really tight pointing angles do help as the extrusion from your furler messes with the wind direction more then just a fore stay. It is all about wind resistance.

[Livia]

I'm confused perhaps I'm not reading your post correctly.

Why do you think you can't point within 90 degrees of the other tack when close hauled? If you boat points high - say at 30-35 degrees - you would have a 60-70 degree "irons" not a 90.

[davidpm]

Originally Posted by groundhog

Hello...
Now theoretically, i guess, i shouldn't have been able to do this? They are all laughing at the retarded man on my home forum. Great fun they are having....

There must be an explanation for what I did.
Any ideas?

Yes popular wisdom would expect that the hank on would give you better pointing over the furler.
What else did you change?
New head sail?
Tighter for-stay or backstar?
In fact any change to the sail trim including the main trim could cause better behavior.
What is you boat? Fractional, masthead?
Have you checked your polar's?
If it got better with the furler we must assume you changed something that was out of whack.

[sailingdog]

Many boats can sail closer than 45˚ off the wind... However, many boats start to pinch when pointed too high and will make much better VMG by dropping off a few degrees.

Now a new roller furling headsail may indeed allow you to point higher than an older, blown out hanked-on headsail. The condition of the sail is far more important to how well it points than the attachment technology used.

[Faster]

Originally Posted by Livia

I'm confused perhaps I'm not reading your post correctly.

Why do you think you can't point within 90 degrees of the other tack when close hauled? If you boat points high - say at 30-35 degrees - you would have a 60-70 degree "irons" not a 90.

That '35 degrees' is APPARENT wind... the angle is influenced by boat speed, wind speed, and the pointing ability. The forward motion of the boat "pulls" the breeze forward.

Plotting your course over ground (in the absence of any current) will show the angles with respect to the true wind direction, and for most boats will be closer to 90 degrees than 70. In fact if indeed you have true 90 degrees between tacks you're doing pretty well in a non-race boat.

[groundhog]

Well, to clarify... if that is possible. This was not a controlled experiment.

Yes, my old hanked on sail was not in good shape, which is typical of a person switching out to a furler.

I had my sail fully furled out, so the headstay foil may have had minimum detrimental effect.

If I recall, the wind was very moderate. Not flat though. Running close to the wind, i did loose a bit of speed.

.........

Sailing dog is saying that many boats can sail closer than 90 degrees to wind...
What happened to me may not be out of the ordinary.

[sailingfool]

I don't think there is any impact on pointing ability from a furling system, I haven't seen a race boat without a headfoil system in 20 years, and many serious PHRF boats actually use a furler system because they want the minor (6 second a mile) adjustment that they can claim.

[JohnRPollard]

Originally Posted by sailingfool

I don't think there is any impact on pointing ability from a furling system, I haven't seen a race boat without a headfoil system in 20 years, and many serious PHRF boats actually use a furler system because they want the minor (6 second a mile) adjustment that they can claim.

Agree with above.

But I'm puzzled as to what the question is. Groundhog, are you saying that the folks on the other forum claim that when switching to a furling jib from a hank-on jib, you will no longer point as well?

If so, I would disagree. As Sailingfool mentions above, even racers use a headfoil system (e.g. Tuffluff) similar to a furler's extrusion to attach the luff of their headsails. These provide a very smooth, low turbulence entry along the entire luff length.

But, if they are saying that a properly sized hank-on jib will be more efficient than a partially furled (i.e., "roller reefed") genoa, then they would have a good argument.

And, as others point out, the biggest difference in pointing ability in your case is probably due to an old vs. new sail, regardless of the furling vs. hank-on aspects.

[Livia]

Originally Posted by Faster

That '35 degrees' is APPARENT wind... the angle is influenced by boat speed, wind speed, and the pointing ability. The forward motion of the boat "pulls" the breeze forward.

Plotting your course over ground (in the absence of any current) will show the angles with respect to the true wind direction, and for most boats will be closer to 90 degrees than 70. In fact if indeed you have true 90 degrees between tacks you're doing pretty well in a non-race boat.

Thanks for the explanation - of course!