A friend of mine tried doing this once, last time he ever saw that sail.
I imagine it is still lying at the bottom of our lake somewhere.

IMHO the best thing to do is to avoid really bad weather or be on the beach somewhere before it gets really bad.

we got ours down in a nasty weather event at Hogsbreath. Pointed into the wind, rolled up the jib and launched the drouge from the bows. Kept us pointed into the wind enough to get the main unhooked at which time we both sat on as much as possible as we pulled it down to keep it from goig overboard.

That wasn't this year, was it, Jay?

not this year. a few years ago when I actually had a boat to sail...

Would like to try that new format for the Keys run... 80 miles off the wind sounds kind of fun as long as you're not the guy holding the spin sheet.

whats a "drouge "? sea anchor?

Pardon my bringing this subject back up, but I was mulling over rigging options the other night when trying to get to sleep, and a related thought came to mind:

1. Is mast bend a function solely of bolt-rope (a.k.a. downhaul) tension, or
2. is it a function of mast compression?

It seems to me that the answer is "2".

Let's take the following thought experiment. Imagine pinning the mainsail head to the top of the mast. Pull downwards on the downhaul (attached to the mast base) with 100 pounds of force. Measure the mast bend.

Next, imagine that you pinned the head and tack of the mainsail to fixed locations on the mast. Then fasten a giant C-clamp on the length of the mast (from the mast base to the head) and apply 100 pounds of compression. Would you get the same mast bend?

Third, imagine running a halyard from the head of the mainsail, around a turning block at the top of the mast, down to a cleat at the mast base. Pull downwards on the downhaul (again, attached to the mast base) with 50 pounds of force. This induces 100 pounds of compression on the mast. Is the mast bend the same again?

I think it would be. If so, then it means that a halyard isn't necessarily bad. In actual use it doesn't double mast compression. Instead, it halves downhaul force. You only pull on the downhaul until you reach the desired mast bend. The system is, in essence a 2:1 cascade, just hooked up on the opposite end of the sail.

Thoughts?

Eric

wouldn't that clamp cause lots of windage? (kidding)

It is not 200 lbs of compression in the above example. It is still only 100 lbs even though there are two different lines (bolt rope and halyard) being pulled on with a 100lb force. Only adding a purchase in the equation would increase this force.

A halyard at the bottom would double compression but the downhaul also stretches the mainsail...so yes and no.

Wanna blow your mind? Think about the extra compression of sailors on the wire. Then think about the side forces generated from the drive of the sail plan. When you get a gust, it tries to pull the middle of the mast to the side. The diamond wires provide a truss to resist this motion...but most spreaders are raked so the diamond wires are no longer in column with the mast. Side force on the mast, when resisted by the raked spreaders, will also push the middle of the mast further forward and bend the mast more. This is why the rake of the spreaders is a tuning item. Heavier teams want less rake in the spreaders as the pressure response to the sideloading is lessened. Lighter teams want more spreader rake as the bend of the mast is enhanced with more sideloading.

Very heavy..... and the position of the sailor on the hull. Angles of pressure change, "To every action there is always opposed and equal reaction" Newton (n.d.)
and or, the mutual actions of two bodies upon each other are always equal, and directed to contrary parts.

I think no. A halyard to the bottom does not double compression. It halves downhaul tension. After all, you do not pull the downhaul to a specified tension - you pull it until you achieve the desired sail shape (i.e. mast bend). If you have a halyard instead of a hook, you reach that shape with half the downhaul force.

That's after taking the slack out of the sail. When sewing a mainsail, one prestretches the bolt rope, and then lets some of it retract into the luff tape before sewing the ends in place. That way, the first couple inches of pull on the downhaul put tension on the fabric along the luff, causing the sail to take the desired shape. You don't, however, want the sailcloth to take too much load (outside its elastic range) and permanently stretch or tear the material. The process above causes the bolt-rope to take up the strain at this point, and more downhaul will induce mast bend. The bolt-rope will have some small stretch, but no so much as to damage the sail.


Now we're entering the realm of dynamic analysis, which is much more complex. However, crew weight, side forces, spreader rake, and tension are the same whether you have a halyard or not, so they don't affect the outcome. What does matter, is rig behavior in a big gust. With no halyard, the sailcloth and boltrope stretch a little, and the mast bends some more under the additional pressure. Hopefully, the extra mast bend is greater than the sail stretch, and causes the sail to flatten and depower (or at least not to power up) in the gust. With a halyard, the sailcloth, boltrope, and halyard all stretch in a puff. The mast also bends, but not as much. You don't get as large or as consistent a depowering tendency. How big this effect is, and how much one sails in big gusts determine whether or not a halyard is a significant consideration.

My boat can be rigged either way (halyard or hook). The vast majority use a hook. It lets us get away with a lighter and stretchier (i.e. cheaper) halyard.

Regards,
Eric