Telltales

[Don Guillette]

As anyone who follows this forum knows I feel telltales are the most important sail trimming devise a mate can put on his boat. I don’t know how sailors trim their sails without them. I can’t and I know what I’m looking for.Let’s test your knowledge of telltales:.What causes the jib telltales to stall (wind is not the answer!)?The optimum jib telltale setup is to have both telltales streaming. If you wanted to “push it” slightly more for that last bit of power from your sail what would you be looking for with your telltales?If the windward telltale flips more often than the leeward telltale, what is happening?If the windward telltale NEVER flips, what is happening?Which set of jib telltales are the most important?What should you do if the leeward jib telltale stop streaming?Which telltale on the mainsail is the most important and why?What is the initial setting for the mainsail top telltale?When the outside jib telltale flips or dances, what is your first and simplest reaction with the jib sheet?When the inside telltale flips, what is your first and simplest reaction with the jib sheet?

 

[Joseph Shirley]

Oh Boy, a test with trick questions

1/ Turbulence or back-winding eddies.2/ If you were looking for power I would like to see the leeward telltales lifting occasionally, like once every 5 to 10 seconds. If however I was trying to work to weather of someone I would like to see the windward telltale occasionally lifting.3/ You are working to weather, sailing as high as you can, and then falling off just a tad as the windward telltale lifts.4/You are sailing bare (further off the wind than you should). You should steer a pinch higher.5/Presuming the jib is basically trimmed, the most important telltales are the steering telltales, about 1/3rd of the way up. If you are sailing in waves and have twist cranked in but are sailing on the whole sail, I would look a little higher like in the middle. And if you have twist cranked in to spill air from the head to ease the amount of heel I would be sailing on the lower telltales.6/ Fall off or sail a little fuller, you're pinching.7/I like the 2nd batten (from the top) for this answer. It reflects the condition across the upper middle of the main, especially with an angle of heel. 8/ streaming aft with a slight rise.9/ If going close hauled to weather I would leave it alone and correct by coming up with the rudder. If sailing full and bye I would ease the sheet.10/ If full and bye I would trim the sheet in a bit. If close hauled I would fall off a pinch.OK Don let me have it.Joe S

 

[Don Guillette]

Quiz

Joe S> Thank you for taking a shot at the at the questions. When I saw 19 responses to another telltale question recently I thought this thread would bring a better response. There are no trick questions - just straight forward situations any sailor would encounter any day sailing closehauled in about 10 knots of wind. I hate trick questions. Some folks use them to make people look silly. That is not my bag. I don't want mates going through what I had to go through to learn how to sail a silly sailboat, so I keep it simple.On the "on the water" seminars I conducted in So Ca, crew members had to know the answers to these telltale questions and after about the second hour of the session they were making the adjustments - along with a million other adjustemnts - on their own before I even got the words out of my mouth. Most importantly, they were able to tell me WHY they making the adjustment. The WHY is everything. If they can't tell me why they did something then we go over it again until the lights go on in their heads. They got so good at adjusting the sail trim controls that they could look at neighboring boats and tell me what adjsutments that sailor should make to his sails. There is nothing complicated about sail trim. It is really very simple. Unfortuantely folks make it harder than it is.

 

[Joseph Shirley]

Don, I think most of us ordinary sailors (myself included) think we

know quite a bit more than nothing, and seeing a test proposed on an expert forum, fear that we will be shown to know far less than we do.Now me , I'm a little different. Because in spite of sailing and racing for over 50 years and believing that I know (almost) it all. I can still expose myself to new ideas and learn some new things. Some times I'm a little hard headed about, and don't believe what I hear, or am told, and I can enter into a spirited debate. Oh and you now say --- just straight forward situations any sailor would encounter any day sailing close-hauled in about 10 knots of wind -- But you didn't say that before, so I was trying to accommodate other situations, Thats why I said Trick questions. Either way however I continue to learn new things and would accept your comments (maybe).Some others may be a little more timid.Good Sailing.Joe S

 

[Stephen K]

..another test taker

Good refresher questions Don. I don't have near the experience as Joe S. ...but am willing to give it a go. Don't know if I'm brave or stupid...1. uneven air flow...turbulence2. for max power, have the leeward telltale lift occasionaly3. pointing well, causing some turbulence on the leeward side some of the time4. heading lower than necessary or sail not trimmed hard enough5. middle jib tell tales are the most important6. ease the jib sheet...7. top telltale on the main is most important cause thats where the wind is the strongest8. initial set is the top batten parallel to the boom..or close to it to hpoefully get the telltale streaming aft9. let it out a little10. trim it in slightly...although I would do nothing until it is flipping every couple seconds.

 

[Ken Juul]

Test

1. improper trim causing poor flow past the sail.2. Inside telltale streaming, outside occasionally flipping up3. Trimmed too tight4. Windward is good, adjust trim to make leeward stream also5. middle6. flow is separated, loosen trim slightly7. Top, shows when twist is proper8. just starting to stream, flipping ok, adjust twist to get streaming most of the time.9. Tighten slightly10. Loosen slightlyReviewing the other replies looks like I got 9 & 10 reversed. Hard to visualize sitting at a computer, so much easier on the boat!

 

[Pete]

I'm just your average sailor....

and the only telltales I pay much attention to are the ones on the shrouds. They, and the Windex, tell where the wind is coming from. I hardly ever feel the need to read, heed, or otherwise try to come to hard conclusions about what the telltales on my main and headsail are doing. I'm not a serious racer and so getting the last 1/10th of knot of boatspeed is not important to me. Yet I like to sail as fast and hard as conditions allow. Trimming my sails is easy: I simply let the main out until it begins to luff, then trim it in a bit. Then I do the same thing with the headsail. Then I look at the knotmeter or speed on the GPS. Since I know the max speed my boat will do is about 6.5 - 7 kts, if I'm in that range I know the sails are trimmed pretty well. If I then happend to look at the sail telltales, they are probably streaming, and that's great. If they do not, that's also ok.Making myself, and my passengers crazy by constantly moving headsails cars fore or aft, moving the traveler up or down, or just constantly playing with sail trim, luff and leech controls, or whatever is not what sailing is about -- to me. I realize this is an unconventional view and that I could probably urge the boat to got marginally fster, but to what end? The idea is to have fun....

 

[Alan]

I can understand why Pete doesn't use telltales.Having to move passengers every time sail trim is needed must be a huge inconvenience so the obvious thing to do is ignore it.However, for those that are interested in correct sail trim telltales are about the only way to 'see' how the air is moving across the sails. Shroud telltales are OK but do not demonstrate the wind pattern across the surface of the sail. Without telltales on the sail it is just guess work. Correct sail trim is far more than just that last 1/10 of a knot. Particularly in light air it is the difference between having to motor to get home or the ability to sail home. Given the choice I would much prefer to sail.

 

[Ross]

I guess that if you were fanatical you could sew pieces

of yarn into the sail on 6x6 centers as they do on wing surfaces in a wind tunnel. With a vang, and a cunningham and sheet cars and outhaul maybe you could get all of those yarns streaming properly.

 

[Alan]

Pieces of yarn

..or nylon strips or cassette tape all work but I would hardly call that "fanatical"!!Like I said there is no other method to trim sails that I'm aware of.

 

[George M.]

For Alan and others....

I think Pete mentioned a pretty fair way to trim sails in his post. It sounds to me that he is using the luff of the main and headsail as the "telltales" they are rather than something else attached to the sail. And as to whether you need to use your telltales in order to sail home or motor, that just sounds bizarre. In the final analysis, I think Pete's method of sail trim will work in any wind condition strong enough to move a boat. Once you get to the point of near windelessness that results in constant sail trimming, slatting of sails, and so forth, I much prefer to turn on the motor and turn off the agony. Finally, strict adherence to trying to constantly trim your sails by reading your telltales correctly assumes (1) that your heading is perfectly constant, (2) that the windspeed is perfectly constant, and (3) that the wind direction is perfectly constant. How often does that happen? Get out there and sail your boat as best you can and enjoy it.

 

[Ross]

Alan ,My point was why stop with just a few teltales?

That will only tell you that the trim is correct right there but six feet away it may be all wrong. So festoon your sail with many teltales and know what is happening on every square foot of the surface. (and make yourself crazy). ;D

 

[Alan]

Ross

That's just not necessary. The important telltales to have on your main are leech telltales which I'm quite sure you already know. Of course, you can choose not to have them or ignore them but I prefer to keep my sailing skills at their best and the only way to do that is like everything else, practice.

 

[Ross]

Alan, Of course I know that ! You use the tools that

work. I am also sure that if the sail was "Blown" the field of telltales would start to show that before you could see it. I use very old sails and am just happy to be able to get out there and enjoy my boat. Maybe with a new suit of sails we would enjoy it a little more but for now I am satisfied.

 

[Don Guillette]

Telltales - Readers Digest Version

Telltales show “attached flow”. Aerodynamicist call it “stagnation streamline”. What it means is if the leading edges of the mainsail and jib are aimed directly into the wind the telltales will stream aft. It is like smoke in a wind tunnel. You want the flow of air on both sails to be SMOOTH and NOT TURBULENT. The telltales are telling you if the flow is smooth or turbulent. If the flow is smooth or ATTACHED (the condition you want) then the telltales will stream aft. If the flow is turbulent or NOT ATTACHED (condition you don’t want) then the telltales will jump up and down. If the telltale on one side just hang down what is that telling you? The answer is obvious – there is no flow of air on that side of the sail.You need LIFT to power the boat. If the windward telltale is just flipping you are at the highest point in the lift/drag curve. When both telltales are streaming lift is at its highest but so is drag. That is why you want them to flip a bit like once every 2 to 3 seconds.You could probably answer most of the questions with the info I just gave you.What caused the jib telltale to stall? The flow of wind became detached from the sail.The optimum setup is both jib telltales streaming but you want to PUSH it a bit and your looking for the telltales to flip a little as I explained above.If the windward telltale flips more often than the leeward what is happening? Your sailing too high and are PINCHING.If the windward jib telltale never flips, what is happening? Your sailing too low and are FOOTING.Which set of jib telltales are the most important? The middle ones.What do you do if the leeward telltale stops streaming? You should head up and sail closer to the wind because your sail is stalled.Which telltale on the main is the most important? The top one as it is your twist indicator.What is the initial setting for the mainsail top telltale? Flowing with an occasional stall.When the outside jib telltale flips or dances, what is the simplest reaction? Ease out the jib sheet.When the inside telltale flips or dances, what is the simplest reaction? Trim the jib sheet in.Here is an easy to remember tip – when the OUTSIDE telltale flips, ease the sheet OUT. When the INSIDE telltale flips. Trim the sheet IN.The above is just the basics of telltales. In my book THE SAIL TRIM USERS GUIDE I devote over 6 pages to reading telltales because they are ABSOLUTELY THE MOST IMPORTANT SAIL TRIM INDICATOR ON THE BOAT. How sailors can sail without them is beyond me.