Rigging Question

[Tedd]

I've been fooling around with Sailaway, a sailing simulator, and I noticed a rigging element that I'm not familiar with. It's a line that runs from what looks like a self-tacking jib track up to, near as I can tell, some point on the mast near the first spreader. What is this? When I use the auto trim feature of the simulation it sometimes adjusts this thing, so the software thinks it's something, not just a random visual element.

 

[JamesG161]

My guess is a self adjusting Mast Stay rigging.
Look at its position on different tacks.
If my guess is correct it should be on the opposite side of the Jib.
Jim...

 

[Tedd]

If my guess is correct it should be on the opposite side of the Jib.

It does seem to be always on the opposite side of the jib. What does a self adjusting mast stay to? Is it to fine tune the upwind stays for different wind conditions?

 

[Joe]

"Self adjusting mast stay system" what in the heck? First of all, what kind of boat is in the simulator and what type rig, masthead or fractional. When you set the game on manual trim operation, as opposed to automatic trim operation, is there a label somewhere for all those lines led aft on the deck? or for the line itself? Though the picture is very dark it appears the line connects a foot or two below the spreaders.... which would be be likely for the topping lift... that is used with a spinnaker pole. At first I was thinking "baby stay" which is a forward facing, adjustable wire used to control mast bend. But... the connection would be much lower, 3 or 4 feet above the deck and it would be very robust... sometimes with a mechanical or pneumatic adjuster. Oh well, I honestly wouldn't lose any sleep with this mystery.... but I'm wondering why there's not a "Sailaway" fan forum you could pose this question towards.

 

[Tedd]

First of all, what kind of boat is in the simulator and what type rig, masthead or fractional.

It's a 38-foot Bermuda rigged fractional sloop. I'm not sure if it's meant to be a specific make and model or just a generic boat of that type, but I suspect the latter.

When you set the game on manual trim operation, as opposed to automatic trim operation, is there a label somewhere for all those lines led aft on the deck? or for the line itself?
...but I'm wondering why there's not a "Sailaway" fan forum you could pose this question towards.

No, that line doesn't seem to be labelled, hence my question. There is a Steam forum for the game but you have to buy the game to post there. Also, being a gaming forum not a sailing forum, I suspect it's more likely that somebody here will provide useful and interesting information.

Oh well, I honestly wouldn't lose any sleep with this mystery....

No sleep lost yet, but thanks for the good wishes! It occurred to me that it might just be something that whoever created the graphics thought looked good, and doesn't mean anything. But it does actually move on the track, which suggests that it's supposed to do something.

 

[JamesG161]

What does a self adjusting mast stay to[do]?

It opposes the Jib Forces put on the mast.
Again logically guessing...
1) Spreads the Mast wind load to more that just a Mast Compression Post
2) Maintains the boat's Center of Forces to more neutral
3) Reduces Mast bending and improves the weather gauge.

Jim...

PS: The reason it moves is from the Mast bending force.

 

[Simon Sexton]

@Tedd ,

Good morning! The rig in question seems to be some variant of a "running back". Running backs were found on fractional race boats up until the early 1980s. The mast on fractional rigs usually accumulate a lot of pressure near the attachment point of the forestay, so the running backs were used to minimize that sideways pressure on port/starboard. Although this looks a bit different and I could be wrong, it looks like it serves the same purpose. Very interesting!

 

[DArcy]

I have seen a self tacking jib sheet run somewhat like that, high up the mast. I believe the idea was to allow a consistent lead length while tacking. It should be run from the jib car however, not the opposite end of the jib car track. The animation may not be accurate however so who knows.
Can you see the jib sheet lead and determine where it runs to?

 

[Tedd]

Can you see the jib sheet lead and determine where it runs to?

I was able to get some better screen shots now that the light is better. (The game only gives you the current "real time" conditions.) As you can see, some of the lines are more representational than accurate, so it might not be possible to conclusively determine what this line is supposed to do. But the line of interest is the one where the bottom and top attachments are circled, in the second image.

 

[JamesG161]

Looks like the simulator was done with RL sailboat architects or advice.

I did a good job of guessing.
Jim...