Schooner type sails, yards and masts.

[admin]

We are moving to the finalization of the sailing model that will properly recreate the behavior of various sail types (standing sails, spankers, square sails). In this matter we have a question

 

What would be the major differences in behavior at various angles to the wind ? Including backward wind pressure and yard positions for 1 and 2.

[Thomas Blackwell]

This is more of a question than an answer, but will Bermuda and gaff rigged vessels be able to sail closer to the wind with less penalty to speed than ship rigged vessels? I'm hoping this is a sailing quality you can add into the game as it will give these kinds of ships their place among pirates, smugglers and captains like me who love these ships.

 

(cough* Yarr! cough*)

[maturin]

Sails 1 and 2? So we're talking gaff rig. AFAIK the gaff rig is just a larger and more flexible ancestor of the bermuda/marconi sail that you see on just about every single modern yacht.

 

Like all fore-and-aft rigs (gaff, bermuda, lug, sprit, lanteen), the gaff is more efficient upwind than a square sail. Schooners can lie closer to the wind. Still, none of the traditional sails are as efficient as the modern bermuda rig. At the end of the day, the gaff is optimized for beam reach. Tacking a schooner is very easy.

 

Not surprisingly, it's harder to go downwind in a fore-and-aft-rigged vessel. It's not just slower, but difficult to make the sails keep their shape. In light winds they can just collapse or wave around uselessly. One way to optimize downwind performance is to move the yards out to opposite sides so that they don't blanket each other. Going 'wing and wing.' However, this only works when going nearly dead downwind. Otherwise, one of the yards will simply swing back into it's old position. http://www.photoseed.com/blog/2012/02/05/reverie/

 

The biggest single difference for yard control is that there are no braces (correct me if I'm wrong): only sheets. So you can't swing the boom around at will; you can only choose to let the wind take it out, or pull it in tight. This also means that backing is not very effective. The most you can do is manually drag the boom over a few feet, as far as the rail. So this isn't something you can do for a long period, without a lot of effort, or in a strong wind. So far as I know, sailing backwards is something that only square riggers could do well. You could probably sail a schooner backwards, but only awkwardly when you are pointing upwind.

 

Furthermore, such vessels have to worry about gybing. That's like the opposite of a tack, where the wind crosses the stern instead of the bow. That is, steering from 170 degrees to 190 degrees. The boom can swing violently across the deck and put stresses on the gear. I'm not too sure about the particulars, as the boat I've done 90% of my sailing on gybed very gently. But on some boats it's a big problem. I'm not sure what aspects of this would need to be modeled in a game.

 

The main thing to keep in mind is that a fore-and-aft rig gives the player much less to do. So control of the headsails is likely necessary to keep him entertained. They behave the same way as a gaff rig, except they can be backed a bit more effectively in order to control rotation. In general, their main purpose in terms of game control would be for aiding turns.

 

 

To go off topic for a moment, headsails are important. USS Chesapeake lost to HMS Shannon because the first broadside shredded Chesapeake's wheel and headsails. With no headsails and no wheel to counteract the new rig balance,  Chesapeake spun up into the wind and presented her stern to her foe.

[Johny Reb]

Maturin's write up is accurate to my experiences sailing a homebuilt schooner made for a lake not the OS. Gybing is very dangerous on my boat if done improperly as the mast is at head level. It becomes less of an issue if you sheet the boom in as you go through and then let it out gently on the new heading. Backing is done by manually pushing the booms out with your hands and that is enough to get you out of irons. The headsails arn't that important on my boat. Usually I set and forget. Rarely do I have motivated hands on board so I have to accept the poor trim. Otherwise I'm yelling at people all day. These are the directions I follow for tacking:

 

The scooner needs decisive handling to tack well. Once you've got it right, she'll never miss stays. Until you do, she'll demonstrate backward sailing happily.

Until the crew is familiar with the vessel, we've found it most useful to do the full Hornblower trick. For people who have dinghy experience, the usual "ready about" etc is an incitement to start shifting, which leads to wet people and an untacked boat.

Here's our procedure. It doesn't feel embarrassing after the first couple of times, at least not if there are no others around, or at least not if you whisper it, or at least...;.

Ready to go about: No-one moves, but is prepared and not watching the scenery.

Let go foresail sheet: The foresail sheet is released to snap back along the boom. With the pressure reduced here, the main starts turning the boat.

Mainsail haul: The sheet holder pulls the boom in, holds it in, and the boat starts spinning into the wind.

Helm's a-lee or lee-oh: Helm is put hard down. Hard down means the end of the tiller, as designed, is above the lee gunwale. This will use the momentum of the boat and add to the spin from the mainsail to pass the boat through the wind. This is also the signal for everyone to start dodging booms as they come across.

Let go main: As the boat comes through the wind, the main sheet must be let go or she'll start weathercocking.

The boat is allowed to fall off a bit if necessary (in this case, a bit like a catamaran) to pick up speed, then brought to the wind again. This whole procedure can be done very slickly, without significant loss of speed.

 

And Gybing:

Scooners can be pretty spectacular gybing - it's that big mainsail. In strong winds, we've found it's less exciting if one gybes from a wing-and-wing position. Bring the boat almost square, sheet the main in very slightly and the fore will swing across to the other side. ("Goosewinging", although strictly a goosewing is when one sail is totally messed up with the gaff out one side and the boom the other). Then you only have the main to worry about as you pass the boat through the wind. The key is control: controlled sheeting in as you start turning and controlled release of the sheet on the new course.

 

Heaving to:

Before heaving to, you should be sailing to windward normally. The end of the foreboom is secured in position--an occy strap or shockcord to the staysail ring on the sidedeck works fine--so that it is not free to swing to the other side. If you don't do this, the boat will end up tacking herself out of the hove-to position.

Once the foresheet is secured, start a normal tack with the helm well down. The boat will come to the wind and the secured foresail will be taken aback, which is what you want. Keep the helm down (tied with another occy strap if necessary) and the mainsail will be in reach for reefing. Pressure on the foresail will tend to push the boat off the wind, and the down helm will tend to bring her up to the wind. She'll gill and fill like this, not forever, but until the slow forward motion this imparts runs you into something. She'll also behave better if you get the jib in rapidly.

 

I don't know if this helps at all since it is for a small schooner but hopefully it will

[maturin]

Great writeup.

 

I doubt we'll see any vessels that are small enough to knock the crew over the head with the boom. But gybing is still somehow significant, isn't it? How could it be represented in-game?

 

 

I'll return to that point about gaff-rig yard control. I don't think that the Q/E and Z/C control scheme is appropriate for it. You don't move the boom freely in either direction, you just let it in and out. That means that the wind direction decides what the maximum boom angle is.

 

So you could do something like this:

Hold C: Haul in the mainsheet to bring the boom (yard) parallel to the keel.

Shift-C: Ease up on the mainsheet to let the wind drag the boom. If you are going downwind, this means that the boom swings out as far as it can possibly go. If you are close-hauled, then the wind carries the boom only forty degrees or so. Basically, the wind wants the boom to be parallel to the wind direction. Essentially, manual skipper on a schooner requires the same sort of code as auto skipper, because the wind has the power to move the boom. If you have the let the boom all the way out when going downwind, and then turn upwind, the boom will change position in an out-of-control fashion. If anything here sounds confusing, it's not. Because we are talking about sailing 101, with zero experience in traditional sail necessary. All this works just the same in any tiny recreational sailboat.

 

In this example, Z and Shift-Z would control the foresail. Then you still have Q/E to control a possibly square-rigged topsail. Or you could use Q/E for the headsails, which behave the same as a gaff rig.

 

So theoretically, we could control every single sail on a schooner without a significant increase in complexity. The problem with the above suggestion is that a square topsail schooner would have to sacrifice control of its headsails, unless we found more key bindings.

[Ryan21]

Just to clarify for the game devs, especially for named controls in game, Yards are the spars only used for square sails, on schooners the lower spar is called a boom, and the smaller upper spar of the same sail a gaff, so for tacking in game sheeting the main amidships should push you head to weather quicker, and easing the headsails, also the square fore topsail will work the exact same way in a tack that it will on a square rigger, it will back and assist pushing the vessels head through the eye, and when the sail will fill you let go and haul and brace the yards onto the new tack.

[maturin]

Do gaff-rigged vessels have any running rigging that control the gaff (upper spar) except halyard and topping lifts?

[Johny Reb]

Only thing I've ever read about and thought about trying on my boat are "vangs" Vangs can be used to pull the gaff in line, or closer in line, with the boom to reduce twist in the sail.

 

First thumbnail is my boat second is a picture of the vang setup I'm referring to

[Ned Loe]

This looks interesting:

 

Forces on sails

 

http://en.wikipedia.org/wiki/Forces_on_sails

[Ryan21]

Yes, all the traditional fore and aft schooners I have seen and sailed on have Gaff Vangs.  For the game I think the simplest way to go about it would be to, instead of yard control, have the main yard controls labelled as and controlling the main sheet, and what would be the foreyard controls controlling the headsail easing and sheeting.  Plus two buttons for fore yard control on square topsail schooners.

[maturin]

Doesn't that leave out the gaff foresail?

 

I keep trying to think of different configurations for smaller vessels, and they always come out feeling rather unergonomic.

[Otakar]

This is how a schooner should run:

Ineffective? Would be nice to see implemented ingame.

*Jib sail would be trimmed like that of aft rig

[Johny Reb]

But the game needs to represent the fact that the schooner can only sheet in. Only the wind can sheet out, so to configure "wing and wing" than the Captain must properly sail the boat in order to get the sails to behave properly. See my description above.

 

BTW, I realized I didn't give credit where it was due in that post. The directions given for the maneuvers were copy and pasted from www.lightschooner.com.

 

I think it would be great if the sails could goosewing when handled improperly. This could happen quite easily when attempting to put the boat in a wing and wing configuration.

[Otakar]

http://www.shpountz.com/gb/navigation.php?procedure=11&

This site has a lot of good information and helpful pictures