[casey1999]

Sometimes when sailing in very light air on a nearly flat sea I am moving along at 4-5 knots. Everything is balanced and trimed well. So then I go to tack and I can never get back up to the same 4-5 knots (more like 2 now). The boat still seems well trimed and it should be going faster. It does seem like the wind has died.

So the question, what is happening? It almost is like the boat is creating its own wind, and when I go to tack, I disrupt the process and never get back to the original speed.

Normally when the above happens, the wind is very light and varialble. Can anyone explain what is happening?

 

[Rhys05]

Is your mast square to the boat? Tensions on the shrouds all equal (and correct)? Jib cars in the same place on both sides? Traveler centered?

 

[casey1999]

Is your mast square to the boat? Tensions on the shrouds all equal (and correct)? Jib cars in the same place on both sides? Traveler centered?

Yes to all.

 

[tempest]

Casey.... does it occur on a particular tack...port or starboard? The fact that you can't seems to get it back up to speed might/could indicate that the rig needs tuning? Is the main centered or in the same position..?

The boat does create it's own wind. It may mean that you need to fall off the wind a bit more to a close reach..until you generate some speed through the water and then you can work your way back up slowly. Also how quickly are you moving the helm over? ..the rudder will act as a break. Have you tried a slower more fluid tack..?

Edit..ignore the 1st questions asked and answered already

 

[casey1999]

Casey.... does it occur on a particular tack...port or starboard? The fact that you can't seems to get it back up to speed might/could indicate that the rig needs tuning? Is the main centered or in the same position..?

The boat does create it's own wind. It may mean that you need to fall off the wind a bit more to a close reach..until you generate some speed through the water and then you can work your way back up slowly. Also how quickly are you moving the helm over? ..the rudder will act as a break. Have you tried a slower more fluid tack..?

Edit..ignore the 1st questions asked and answered already

Does not occur on one particular tack. I tuned the rig, maybe it is not optimum, but all wires are tensioned to best specs I could find. The mast straight port to starboard with about a 2 inch rake to aft. The main is centered. The loss of speed would happen when close hauled. When the wind is light, I use a slow rudder movement.

 

[nolatom]

Is it possible your main is over-trimmed and still in "high gear" from the previous tack? Some boats need eased sails to get started (low gear) then we click them in as we accelerate. But I figure you already know this well.

You mentioned flat water, so that's when we can get a lot of apparent wind out of just our boatspeed. so the difference between flat blades and high gear and billowy blades and low gear may be a lot.

If that isn't it, and it probably isn't, then I too am lost. If your hull, rig, and sails are symmetrical, jib leads similar, then I just dunno.

 

[capt vimes]

If everything is the same on each tack (including ballast in form of tanks) then the "error" must be with the helmsman...
On a tack you loose speed... So the apparent wind is suddenly different... Steering by the compass does not help...
Get a feeling of the boat on the new tack, and once she is on speed again, check out where she is going with that same trim...
Tempest said it in different words, but he is absolutely correct...

 

[smurphny]

Maybe the next time out you can compile some polars for different tack angles. That will force you to keep a close eye on heading and apparent wind. It's handy to have the polars in any case. If current is 0, the traveler is centered, you are on same headings relative to the apparent wind, and the wind remains steady, it would seem that the boat should achieve approx. the same speed once it's set on the new tack.

 

[casey1999]

Is it possible your main is over-trimmed and still in "high gear" from the previous tack? Some boats need eased sails to get started (low gear) then we click them in as we accelerate. But I figure you already know this well.

You mentioned flat water, so that's when we can get a lot of apparent wind out of just our boatspeed. so the difference between flat blades and high gear and billowy blades and low gear may be a lot.

If that isn't it, and it probably isn't, then I too am lost. If your hull, rig, and sails are symmetrical, jib leads similar, then I just dunno.

I think you are all on to somthing. When I tack close hauled (in light winds), I normally keep the main sheeted in tight. Maybe I should ease it a bit and sheet in as I build up some boat speed. Then the true wind combined with apparent wind would make the tight main sheet the correct trim. Sounds like you are right, I am oversheeted for the boat speed and just stalling the sail and going slow.

 

[wikiwiki]

Come out of tack slightly powered up ( ease mainsheet a hair )

Little rudder

 

[tempest]

Casey, That would do it.

FWIW in the light winds, flat water that you described, I'll ease my outhaul a little and also make sure there's a slight curve at the foot of the genoa ( not sheeted in too tight)

 

[jimrafford]

Your sails are stalled. Soften the trim til your speed starts to climb.
One Bermuda race I was on helm in really light conditions at nite. When I started my watch our boat speed was terrible and every one going off watch was frustrated. Once they were below I asked my team to let the sheets out til the sails started to luff then bring them in a little. Immediately the boat speed started to climb. As the speed climbed we trimmed in. Within 1/2 hour we were doing 5 kts. We continued this thru the rest of our watch.
When the previous watch came back up, ( it's still dark ) I advised them of the last 4 hours and what we had done. They said the sails don't look rite and started trimming in and flattened them. Our boat speed dropped quickly back to under 2 kts.
I said "idiots" and went to sleep.
Needless to say we were last that year.
Jim

 

[christian.hess]

when in doubt let it out

you are pinching...classic symptom is after a tack

like jim says above luff em to hell...and haul in till it barely luffs, then go in once more and leave it be...

 

[christian.hess]

Ill bet you gain even more by letting the mainsheet out and get a nice shape to the sail, letting outhaul and downhaul slack a bit...

remeber when tacking its not just a slow tack that will make your turn more efficient...remember the shape you are wanting or the track you are aiming to set...

you head down a bit gain speed slack off a bit turn over...then after gaining speed again over on the next tack you tighten up again...only after gaining speed and correct angle again

try hauling in the jib after tacking first...then in a nice slow motion tighten up main...after setting the job correctly...I bet you will feel the difference

focus on the jib and efficiently tacking it over then main...

if you just tack over without even easing the main you are asking to stall...

 

[MarkofSeaLife]

Before you tack you know about where you will be headed on the next tack... About, say, 90 degrees from where you are heading now... But instead of doing a 90 d tack do a 110 deg tack, so you are tacking to 60 degrees to the wind instead of 45. Then as the boat speed picks up you can come up harder on the wind.

The others are right too about easing sheets a bit till you get speed back. Your airfoil wants a nice big curve in it in light winds.

 

[Chas H]

I posted the video link below in another thread. It may be helpful here.

Tacking the windward traveller

I also do not trim the jib tight until gaining headway on the new tack.

 

[smurphny]

Of course the most important element in the procedure is to maintain speed through the tack. I've always found that when I've screwed up a tack and needed to gain a lot of speed, it was because I did not round up with enough speed to carry through to the next heading. It's a great feeling to really nail a tack, even in light wind. To me it's mostly getting wind in the the sails asap on the new side before the boat loses much speed. It's all about timing. As Mark indicated, falling off a bit on the new tack will get wind into the sails. Ready to come about----hard alee!

 

[tommays]

My 150 has several small round windows with very visible tell tails

I trim the sail to distance X off the spreader and helm to the tell tails ignoring the windex and get very repeatable speeds

 

[christian.hess]

you should learn to tack without the use of any aids or instruments...after that get into the nitty gritty

 

[tdw]

I'm wondering if she is in daysail/club race mode or cruising mode ? She's an S&S 34 so pretty moderate in design, no you beaut racer.

To my mind then, and given our previous boat was somewhat similar, the go is to drop off a few points and ease off your sheets as you approach the turning point giving yourself as much power as possible going through the tack.

Theoretically that means more speed as you exit and prepare to harden up.