Locating and using wind telltales?

Good post!

I use the telltales all the time - I have added a wind direction streamer to the top of my mast(s) but this can get wrapped around the mast due to roller furling/unfurling, especially if I have dipped it in the drink when putting the mast up. It is just a simple piece of recording tape pulled out of an old audio cassette and tied on - easy, cheap, floats in the breeze well and I have loads more where that came from if & when it wears out.

As to the telltails on the sail - I have two sorts on my two sails - one type are woollen thread streamers, the others are like ribbons. I have added a second set of woollen ones to that sail because the original ones were set higher up on the sail and had a tendency to catch on the panel seam and hang up.

Either way I have noticed two particular things about the telltales - one is that the wind is almost never particularly consistent from the perspective of these little boats; in other words it is rare to be able to maintain the same course and heeling angle and apparent wind direction for more than short periods at a time so the telltails will be constantly shifting and telling a different story. This is fine - it is all part of the challenge of sailing these boats - but it does mean you need to be very responsive to the wind and boat to be able to optimise the sailing performance of the sail as indicatred by the telltails. As a a result, when I am sailing I am constantly tweaking the sheet and rudder and my weight to try to keep the telltales streaming in the right direction.

The second thing is that the excessive (if I can call it that) bending of the standard mast really plays havoc with sail shape and consequently the way that the telltales 'indicate'. Recently I 'upgraded' to a carbon fibre mast that I put together using two tubes bought from a local fishing rod manufacturer; this is much stiffer than the standard alu mast and seems to have made a significant difference to the performance of the sail and the telltales are far more consistent in their readings. I have no basis for testing this theory (because I have nobody to sail 'against') but I believe that the sail delivers better performance on the carbon fibre mast than on the stock mast simply becase the foil shape is so much better - it certainly the boat is a lot more twitchy in terms of heeling which I put down to there being less flex in the mast to absorb/spill gusts and the sail shape looks a whole lot better in stronger breezes/gusts.

Personally I am happy to try to keep both telltails streaming aft in the 'approved' fashion - I am sure that in bigger/higher performance boats with fancier sails and over longer distances this probably makes a significant difference but for my part I am usually happy enough to be enjoying the sailing experience (as opposed to pedalling/paddling) rather than worrying too much about whether or not I have really tweaked my sail to the optimum.

A 'thread' out of one of those woven poly tarps also works well and it lasts a bit longer too...

Tell Tails are used for a variety of wind indications.

Up high on the top of the mast or on a support stay (shrouds, forestays and bridles on catamarans), would be free to indicate apparent wind direction and undisturbed by the sails.

In the body of the sail indicate air flow over the sail surface.

On the leech of the sail help to indicate under or over sheeting as well as sail twist.

We simply place the basic sail body ones as a starter. These are the most common used in sailing. I like the leech tails and always have a free swinging wind indicator if I'm racing. I have a couple of diagrams that might help. Designed for Catamarans, but really similar.

How to place them:



How to use them:


The basics are to try and get both standard tells flowing. I would rather see the windward one stall than the lee side. Sheet out or change course until they flow. Then sheet in a bit.

The upper 3rd of the sail is a good location for "leech" tell tails. If you sheet too hard the tell tail will wrap to the lee side. Not sheeting hard enough and the tell tail flows straight aft. The right sheet tension typically causes the tell tails to flow aft then wrap to lee and repeat... alternating. Very difficult to get it all flowing correctly on a Kayak sail due to the limited tension and sheeting controls and no traveler. Catamarans have battens, downhaul, outhaul, and travelers on the sheeting systems... all work together to trim properly for different points of sail (directions you are sailing compared to the wind).

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

Both of my diagrams are only on the weather side. Does not indicate the lee side.

Love the gif versions you posted. Nice.

I think you want the lee side less stable. Disregarding the tell tails, you sheet out until the sail luffs and sheet back in until that stops. Then use tell tails for finer adjustments.

Proper settings create a vacuum on the lee side, so makes sense its flow is less stable.

_________________
Matt Miller
Former - Director of Parts and Accessory Sales
Warranty and Technical Support
Hobie Cat USA
(Retired 11/7/2022)

I have never really understood the leech tell tails before... now I do! Thanks Matt