Tell tales

[chrisfsi]

Upwind, I am managing to keep the tell tales above the window flying straight back on both sides, which I believe is good... But I struggle to get the top tell tale (towards the top of the sail, about 6 inches from the luff) to do anything other than fly either round and round, or upwards.

My feeling is that I can improve things by adjusting either the downhaul or the vang. Is this correct, and if so which? Or is the top tell tale less relevant?

Thanks..

 

[49208]

6 inches from the luff is still fairly turbulent air off the mast - try moving them back to at least 12" - 15"

How far back are the lower telltales ?

 

[chrisfsi]

The bottom ones are above the window - about 6-9 inches - , with the front one slightly forward of the front edge of the window..

 

[Chainsaw]

Upwind, I am managing to keep the tell tales above the window flying straight back on both sides, which I believe is good...

Depends enitrely on the wind strength and angle. More wind, tails more stable. Change the angle and strength and tails flying at 45 degrees or so upwards is fine. When in doubt, keep the leeward tail flying.

But I struggle to get the top tell tale (towards the top of the sail, about 6 inches from the luff) to do anything other than fly either round and round, or upwards.

Could be too much vang. Try pulling on more cunningham, then if that doesn't work, less vang. That section of sail may be too flat. Could be too close to luff - turbulence. The only way to check that is to put a few more tails up there and go out and experiment. Then take off the ones that aren't telling you anything.

My other theory is that the standard top laser batten is too stiff. Anyone heard about more flexible battens being ok for that top pocket?

My feeling is that I can improve things by adjusting either the downhaul or the vang. Is this correct, and if so which? Or is the top tell tale less relevant?

Thanks..

Experiment. As your sail ages, or if it is already old, that will have an effect on the "recommended" position of the tails too. The placement of tails on the laser sail is a little different to say, a 10metre keeler. I've found that there isn't much point having tails in the last 1/2 to 2/3 of the sail and instead rely on the leech tails just below each batten position.