I sailed my Stealth for the second time last Sunday. The first time I sailed I had issues with trimming the main so I added two sets of telltales to help me figuring out what was wrong: 25 cms from the luff, one on the bottom third of the sail, one at the top third.

So in 10-12 knots of wind going upwind and trapezing I can get the lower telltales to fly just fine, as well as the top leeward one. But the top windward telltale is never flying straight. If I bear away to get it to fly I'm doing square tacks and I'm not longer beating to the mark, worse my bottom leeward telltale starts to act.

For me this indicates that I'm not sheeting enough, and I should tension the leech to reduce the twist, but if I sheet in more my leech hooks and the boat stops (it's impressive how this thing can stop. Coming from a 5.2 it was easier to keep it plowing forward on its own momentum, not the instant punishment I get with the Stealth!).

So, anything I can do to get a flow all over and not just the bottom of my sail? Any other string to pull to get this to work better? How is the downhaul having effect up there?

Note: I have an oldish Stealth main, not a newfangled square top F16 main, if it makes a difference...

In 12 kts I would be starting to add a fair bit of downhaul as I would be well overpowered upwind. Maybe you need more downhaul, so you can sheet in harder and so less drag of a twisted off sail.

Hi Pepin,

although I have a different boat I have the some problem as you. I posted the question some time ago, but I am too stupid to find it anymore. There were some good replies and a lot of pictures of trimmed sails.
Unfortunately there was no agreed opinion about what to do. If I apply more downhaul, the boat feels a bit depowered. My personal conclusion is that I have to accept some non optimum flow at the sail...

However if you apply more main sheet and you want stop hooking the main, you have to apply more downhaul as well to open the sail again... that's at least the theory.

I will try to find this posting again.

Cheers,

Klaus

Could it be that the battens in the top aren't stiff enough? Or not stiff enough anymore?

Gill

Well I am not too stupid to find this old posting...
Here is it (at let see if I amange to attache a proper link...)
http://www.catsailor.com/forums/sho...;amp;page=0&fpart=2&vc=1
or
Posting about sail trim
Have a nice reading.

Cheers,

Klaus

Nobody should sheet F16 sails on teh feel of power, only on the feel of speed.

In quite a few instances my own boat goes faster when the rig feels less powered up. When I trim the draft back in I lift easier but also slow down. On a friends boat it is the same. We did a upwind check against a well sailed Infusion F18 just a few weeks ago and it was light winds. At first we could point with it. Pulling on the downhaul was the last things on our minds as we felt that we were looking for more power not less. Finally, we tried downhaul as in the past we had learned that when all else fails its the downhaul that need retrimming. And what do you know, the bota immediately pointed with the Infusion at the same speed. The rig looked flat and open in the top and felt slightly less powered BUT is was faster and pointed better.

F16 sails want to stream, not work.

They are different to many other boats.

Wouter

I gave up on my windward tales a long time ago. Sailing uni, if I wanted the windward tales to fly I would have been way overpowered with the trav midline or the trav too far out and then footing too much. Dunno... maybe it is me.. probably is, but I fought that fight for a while. The leeward tales shoudl definately be streamed the whole time. I sail with the trav down about 3-4 inches with good (not max) mainsheet tension with moderate downhaul in average winds and that is when the boat feels best. Sheet in anymore and the boat slows and feels sluggish.
Of course, I haven't had much opportunity to sail against other F16s but I have done well against an 18HT sailed by a very good sailor. I don't generally point as high as he does (solo on the HT) but I think my VMG is as good if not better.

Good call from Gill on the batten suggestion. The second batten from the top was not set properly into its batten pocket on the mast side. I noticed it today and reset it into its proper position. Hopefully that will cure the problem!