Tell-tail windows in genoa

[Hayden Watson]

I am buying a new main and genoa this winter and am thinnking about adding one or two tell-tail windows to the genoa. For those of you who have them what are your thoughts? The bottom only? Bottom two? All tails? Or are they a waste of money?

What say you?

 

[garymalmgren]

I had a window on my old furling Genoa.
It was about 5 feet up from the deck and easy to see.
The sail was very old, ( at least 20 years old) but the clear plastic insert was not too faded or scratched, so they seem to be pretty robust.
The sail furled as usual, so the window didn't have any effect there.
Just had a new sail made last year and didn't fit a window.
I can see the opposite side telltail well enough through the sail.
My conclusion is that there are no real drawbacks and if you really want to keep tabs on your foresail trim, they are good.

As for how many to fit, on a 30 footer one well placed would be fine.
The sailmaker would be the one to consult about that.

gary

 

[shemandr]

I would say middle only. That I would consider that the average of twist. Top ones I can rarely see from the helm because they are often blocked by the main. The bottom aren't in as clean air. I think fewer are better.

 

[Davidasailor26]

We have 3 sets of tails, with a window for the lowest set. In our case the lowest set is the only one that’s especially easy to see when the dodger, connector, and Bimini are up. When racing we remove the connector so it’s easier to see all three. If I were getting a new sail I’d probably get the same arrangement. The only downside I’ve seen of the window is if it gets a loose thread on its stitching and the tale gets frayed the tale can snag and get stuck in place.

 

[dlochner]

I have never had telltale windows and never felt the need. Generally sail cloth is translucent enough for the shadow of the leeward telltale is visible and of the two the windward telltale is the more important and that is visible.

 

[jssailem]

Agree with @dlochner that the sail cloth is translucent and telltales made from red/green nylon are visible in all but the worst inclement weather conditions.

Only sails with windows, I have seen were on Genoa’s that were cut full as deck sweeper’s. The window was there to see other boats on opposing tacks.

Here is a recent image I received from a fellow SBO member. It illustrates the visibility comments about telltales.

 

[Hayden Watson]

@jssailem I agree that on a day like that photo was taken they are completely uneeded but when it is overcast or worse, you are sailing along an hilly tree covered hillside, it is almost impossible to see the leeward tail.
Fortunately, here in the PWN, it is always sunny, and the shoreline is flat, so the sail is always backlit with nice blue sky.

 

[dlochner]

I wonder if it is possible to have the inner tell tale streaming perfectly and the outer telltale not streaming correctly? I don't recall that typically being a sail trim problem. I have seen the opposite problem, outer tell tales streaming horizontally and inner ones too high or too low.

 

[jssailem]

Yes. It is possible. It’s all observed in the air flow regions External, Transitional, Laminar, Turbulence, air layers that are on the sail as you trim the sail in the constantly changing air currents.

I’d encourage exploration of the discussions and musings of Arvel Gentry
http://gentrysailing.com/pdf-theory/Aerodynamics-Of-Sail-Interaction.pdf

http://gentrysailing.com/pdf-theory/Boundary-Layer-Flow-and-the-Headsail.pdf

I had forgotten that Gentry did have small clear “windows“ on the sails. It is explained in this link.

http://gentrysailing.com/pdf-theory/Checking-Trim-on-the-Wind.pdf

 

[Sandy Stone]

It is certainly possible for the outside, leeward telltale to not stream properly while the inside one is, and that is when the jib is overtrimmed, or stalled. That is probably one of the most common beginner mistakes, and a definite speed robber. It is so important to avoid this, if you are doing any racing at all, that I would always insist on having telltale windows. Sure, you can make out the leeward telltales when the jib is backlit as in jssailem's picture, but they are impossible to see when the sun is shining on the near side of the sail.
The only downside to windows is the slight additional cost, but I feel they are well worth it.

 

[dlochner]

Thanks for the replies. I know the theory and why the tell tales should be streaming evenly and breaking evenly. It seems that I fiddle more with getting the inner ones streaming right and never seem to have a problem with the outer ones. We're going to make this easier next season. Santa came early.

 

[jssailem]

Sweet Dave... You must have been a good boy.... On the Nice List

 

[dlochner]

Sweet Dave... You must have been a good boy.... On the Nice List

Not for me. Second Star did a good job last year in our travels and deserves some new bling. But she complained bitterly about the almost correctly trimmed Genoa. Something about the skipper being too lazy to go up on the side deck and adjust the car leads.

This is the First Mate's present.

 

[jssailem]

Well there you go.
One reason to question the benefits of having a crew with critical thinking abilities.

 

[Joe]

I am buying a new main and genoa this winter and am thinnking about adding one or two tell-tail windows to the genoa. For those of you who have them what are your thoughts? The bottom only? Bottom two? All tails? Or are they a waste of money?

What say you?

Bottom only. You only need to see both sides at once when steering. The upper two sets are used for setting the lead blocks and sometimes the halyard tension. So once you get that set you are mainly concentrating on the lower tells. Uh, that's why the call them the steering tells. Usually the sailmaker includes tell tales with the sail, and usually a small lower window too. If you're ordering a large, low cut genoa they will usually offer an optional, much larger, window(at additional cost) in the forward corner where the first set of tells will be.... but that window is for visibility....rather than seeing the tells. A regular or high cut sail is pretty easy to see under, but large, low cut sails (often called "decksweepers") will obstruct the driver's view to leeward if he's sitting to windward. Very important to see what's to leeward when you're in a crowd, trying to round a mark, etc. Think about it.

 

[Hollyberry]

If the sun is hard on the windward sail surface it can be very difficult to see the leeward side.. I think a window helps - as long as it's in the sight line of your typical steering position.

One thing that drives me nuts is when a telltale hangs up on stitching - whether a window or a sail seam.. Try to ensure the telltale cannot reach a sewn seam...

 

[BarryL]

Hey,

what kind of sail are you buying? With a Dacron sail in a typically see through the sail well enough to see the outside tell tails. With a black racing sail you will definitely need a window. I would want at least 2 windows and preferably 3.

barry

 

[stickinthemud57]

Hey,

what kind of sail are you buying? With a Dacron sail in a typically see through the sail well enough to see the outside tell tails. With a black racing sail you will definitely need a window. I would want at least 2 windows and preferably 3.

barry

My experience - I went from white 5-oz main and 4-oz genoa - no problem seeing both port and starboard tels. I am very glad my jib has the two telltale windows it came with. The main doesn't need it as the tels at the leech suffice.

Tell us more about the sails, if you would.

 

[Hayden Watson]

Tell us more about the sails, if you would.

I am only looking at tell-tail windows for the genoa. The genny will be a bit larger than 135% and built with 6-7 once dacron. My current sail is about the same size out of Defender Supercruise Dacron and I have been very happy with it. The main will not have any windows and will probably be the same cloth. It will have two reefs and four full battens.

Not for me. Second Star did a good job last year in our travels and deserves some new bling. But she complained bitterly about the almost correctly trimmed Genoa. Something about the skipper being too lazy to go up on the side deck and adjust the car leads.

This is the First Mate's present.

View attachment 211547

I did that upgrade several years ago and @jssailem was one of the first beneficiaries of the warm cabin on a chilly early May morning. I am glad to see that you are installing the muffler right from the beginning. He can also tell you what it is like without the muffler. Sounded like a 707 run-up. With the muffler, the burner cannot be heard at all and the only way that I know it is running is by the quiet whine from the water pump. Best heat in the world. I designed and installed my own system. I have a summer loop that bypasses the fan coils and only goes to the domestic water heater. I also have values that interconnect it to the engine so that I can use the espar to heat the engine or the engine to heat the water heater. I filled the whole system with a pet-safe Propylene glycol antifreeze in the engine and the hydronic.

 

[Apex]

I am buying a new main and genoa this winter and am thinnking about adding one or two tell-tail windows to the genoa. For those of you who have them what are your thoughts? The bottom only? Bottom two? All tails? Or are they a waste of money?

What say you?

Typical from what I pbserged, is lower only. Personally I LIKE the idea, and required for carbon sails