Survival tactics..

OK. Down wind in heavy+ winds, can you sheet tight and travel in to reduce attack angle?

Yep.

yes - but watch for a chinese gybe that will overpower the rudders in a split second. With wind come shifts.

And you want to be as close to DDW without risking the unintentional gybes as Jake mentioned.

So, how do you get there? Do you sheet/travel in first, then turn down, or turn down then try to sheet/travel in, or do you sheet first, head down then travel in, or something else altogether?

Personally, I've never even tried this, but there have been times when I wished that I had.

Obviously, this is all assuming sloop or uni with no chute...

Mike

If it is really heavy plus survival, you may come to a ddw course where you can sheet in, but you will never come out of it. Don't ask why I know...
The survival mode is head in the wind, take boards and rudders up, sit on the bow (hold tight) and sheet in. YOu can any time go back and sail upwind. Works also in surf.

Cheers,

Klaus

Go upwind, releae the sheet, but not the traveller and turn quickly the sterns into the wind. Sheet quickly in. The crew can take the boards up, if she/he dares to go forward. Be careful on the tiller, the leech is now the luff, like Laser sailing. As I said, the problem is changing the course again. In opposition to a Laser or windsurfer, your sail swings only to the shrouds.

Survival? I all depends on the circumstances. One of the possible option in survival conditions is to turtle the boat on purpose, it is far more stable pointy end down. It's also going to slow it drifting giving you more time to think and/or call for help.

Or go head to wind and get the main down. Roll it tight, and attach it solidly. If it it windy you'd be surprised how well you can point or the speed you can reach DDW with just the mast!

So this is a Chinese gybe? Yip!

The equipment-related chinese gype at about 2 minutes.

Actually, that probably isn't gybe. The bow looks to be knocked around by a big wave and a hard tack was the result. Chinese tack?

That, as they say, is NOT fast...

The real stunner for me was the guy saying (repeatedly, even) "Get me a knife." Why everyone doesn't have one attached to themselves at all times on something like this amazes me.

Mike

no joke. why wouldn't they have knives

Are Russians allowed to carry knives?

I was waiting to see the main come flying across, that is what I would be afraid of.

The reason for the post is... I once sailed from Miami to Key Largo and the wind unexpectedly built to about 30+ from the North as we were more than half way down the bay heading south.
We were traveled out so far that the battens were bending to fore against the shrouds. At that point we were "pointing the boat" not sailing it.

I think it was the '05 steeplechase that started out that way. It took us three attempts to bear away coming out of Angelfish Creek...once we did make the turn, there wasn't much sense of relief as we were not very much in control dead downwind with main and jib.

So how many people have installed reefing points on the mainsail to depower the rig and give you speed rather than abundant heeling force. Most monos can do it quickly and easily on and off the wind, why are reefing points not standard on cat main sails?

To depower a sail you can make it smaller (reef), or flatten it. Modern high performance beachcats focus on flattening it - by application of high main sheet and cunningham tension. In addition, the top of the mast will tend to bend off to leeward which 'spills' pressure when the apparent wind is forward. The combined main sheet and cunnigham tension place a reasonably large load on the head of the sail. This is why most beachcat main sails latch to the top of the mast - as that is a robust anchor to resist those forces rather than it all being on the halyard.

Older designs with lower sheet / cunningham tension (such as the Hobie 16) did have the ability to reef the main. In those cases, the main halyard is loaded and typically has a wire section with a slug that is trapped in a V on the front of the mast. A couple of slugs are placed on the wire section for the full and reefed sail positions.

When I have seen those older designs reefed the mains do not look very flat to me - which means they still develop a lot of power reaching or going upwind. In a 'survival' mode sailing downwind the reduction in sail area would probably be useful. It seems to me that the window where a reefed main would provide advantage is narrow. Above a certain point you'd better turtle the boat or take down the sails (difficult in big wind/wave state).

Hobie Tiger mains have been supplied with small reef point grommits - but not reinforced at those locations. I think they were included to comply with a class rule rather than for real world use. Smythe put reef points on one 18HT sail I've seen - but I never saw it sailed with the reef in.

Chris.

In addition to providing a solid anchor point with the hook at the top of the mast, it also reduces compression on the mast by 50% over having a halyard carry the sail loads back down to the foot of the mast (again).

…” the main halyard is loaded”…

Not on the H16s from the early 80s. Like you said, the slugs in the halyard clipped into the fitting atop the front of the mast just like the current design. So, the only part of the halyard that had any load was from the shackle to this fitting. Not sure about older (70s) models.

The main reasons that I’ve heard for Hobie discontinuing the reef setup was the introduction of the Comptip (and requirement for the metal part of the halyard to not come down to where people could come in contact), and the market feedback that no one really used it. Matt Miller might have more info if he’s reading this.



I’m trying to wrap my head around this concept, but it’s not working for me. The load with the main attached to the top of the mast is the same as if it’s brought back down to the bottom. If you take away the purchase, you don’t take away half of the load, all of it transfers to the bolt rope, which extends the length of the mast.

In other words, you reduce the load on the bolt rope by fastening the hayard at the bottom of the mast, but the load on the mast is the same either way. What am I missing here?

Mike

Nope the compression load is 2:1 on the top the mast if the halyard is cleated at the base. It's 1:1 if it utilizes a halyard hook.

OK, so you're repeating Jake. Can either of you explain? Especially since it loops over the top of the mast (H16 doesn't hook behind the mast like other cats).

I'm feeling so confused... :-0

Mike

If the hooked sail is pulled down via the downhaul the mast is going to present a nice curve, flattening the sail. If you have a halyard created at the bottom of the mast instead when you pull the downhaul the result will not be the same as the pressure on the front of the mast, where the descending halyard line is, will be getting on the way of the mast bending. Routing the halyard inside the mast track doesn't solve the issue either as now the under tension descending halyard need to follow the bend of the mast which is it going to do only by pressing on the sail rope. That's one reason we use hooks.

Now the second reason is compression. When you have a hook and pull on the downhaul the tension applies only on one side of the mast. If your halyard is cleated at the bottom of the mast the pressure applies up *and* down the mast, doubling the amount of compression the mast has to sustain for the same downhaul amount.

And a third reason is drag. Having the halyard hidden in the mast track reduce drag, and you can't put an under tension halyard inside the track.

If the sail is hooked at the top of the mast and you pull down with 100 lbs of force, you have 100 lbs of tension on the mainsail luff and 100 lbs of compression that the mast has to resist.

If you have a halyard that turns around a sheave at the top of the mast and is cleated at the bottom (i.e., the halyard cleat at the bottom of the mast is what keeps the sail from falling down) and you apply the same 100lbs to the tack of the mainsail, you have 100 lbs of tension on the mainsail luff and 100 lbs of tension on the halyard. You now have two 100lb tensions that the mast has to resist equaling 200 lbs of compression on the mast.

ahhh, good times with the tall rig...

If I recall correctly, the wind was switching around and we still had a chinese gybe when we had it sheeted in a bit. It was at that point we "let her fly".

Gotcha, makes sense. No purchase until you get past 2:1, even then, it wouldn't help if tied to the bottom of the mast. Hard to wrap my head around this today for some reason. Way too much blood in my alcohol system (and yes, I'm Irish)...

Mike

Actually, sheeting and/or traveling in increases the angle of attack. The goal being to increase the angle of attack to the point that the flow separates from the lee side of the sail and causing it to stall- resulting in a large decrease in power. The problem with this technique is that if the wind direction moves forward or the boat heads up to the point that the flow "re-connects" you will experience a large, rapid power increase.

If you bear off too far, the airflow will switch to clew first- i.e. sailing by the lee. It's doable, but not stable, so the potential for a flying gybe is pretty high.

After all depowering that can be done through tuning is done, reducing sail area is the safest and most effective next step towards depowering.

sm

Flattening certainly extends the usable range of a sail plan, but there always exists a wind speed where reefing becomes the only solution to keep sailing. Boats capsize with their crews in the wire, sails feathered and flattened.

I like the self-standing telescoping mast that Rob Denney devised. The mast top lowers with the sail, leaving no draggy mast tip up. The retracted mast also becomes stiffer, though, like in any telescope.

Not that I'm an expert, but if you were pointing into the breeze, couldn't you also drop the main?

What type of boat are you sailing.

I sailed in a Tornado regatta that blew 36 average, gusting 42 (confirmed). We ran very deep under kite, keeping both hulls in the water, crew on trap as far back as possible and myself leaning over the rear beam. Kite was eased a long way, main was sheeted reasonably tight with only a slight twist.

Gybes were ugly though. Only moving a few degrees through them and battling to keep the windward hull down after the gybes.

When you talk about depowering, I assume you mean, as far as the main is concerned, maximum downhaul and minimum outhaul. How about mastrotation - fully in? Reducing sail area is on modern F18s not an option since we don't have self-furlings jibs anymore ...

bingo! Ballistic guidance... good thing we never ran out of water.

I have the answer on how to handle survival conditions -- go out on a Wave and enjoy the hell out of it.
I remember a while back we were racing Waves in gusts to 45 mph at Lake Eustis. Downwind I was wishing for a longer bow.

Normally downwind you aim the Wave for the leeward mark. But, in those conditions you tacked downwind, sail all the way out. When a big puff hit, instead of heading down, like in a high-tech cat, you headed up to dump the air entirely. And when jibing, try to wait of a lull, and after coming about, instead of heading down for stability, do the same thing by heading up and dumping all the wind.
Upwind was just plain fun.
Rick

Yes, tension the sail to be as flat as possible- max outhaul & downhaul. In a true survival situation, drop the main and go downwind under jib alone. I saw one of the top H16 sailors in our area do this once a few years ago. We had to get to a tiny beach dead downwind that was situated in an area surrounded by pilings, bulkheads, and docks. Downwind under jib alone is no big deal. Its only when you have to try to go back upwind that it is an issue.

sm

when the wind was too strong for the first day of midwinters last weekend in pensacola we did some round robins on the waves Kirk had on his beach. Crazy fun. Wish I had the knowledge to tack a little downwind (I confirmed with Kirk beforehand about the DDW approach). I clocked 11kn downwind. I tried to get forward once but was soon corrected by the bows. Upwind it was fun- had to stay on top of things. You should have seen the waves on a downwind start in a 35kn puff!

I respectfully disagree with this analysis. Unless the combined force of the halyard and the cunningham are additively greater than cunningham alone, the compressive force on the mast proper seems identical. However, the distribution of the load is across *both* the halyard and bolt rope/luff rather than the luff/bolt rope alone (i.e. Cunningham and hook). The consequence of having a halyard distributing a portion the load would be probable loss of mast curvature and consequent increased chord on the main. (i.e. force distributed along the main halyard and the mainsail luff, vs only mainsail). Additionally, given the impressive shaping curvature of modern cat masts, the main halyard force could wedge the halyard into the boltrope channel, possibly jamming the bolt rope and placing an uneven load on the mast near its maximal point of flex. (I'm thinking that would be a bad thing in a big breeze.)

My advice? Make sure your hook works easily, Take down the main (if you can), roll it, stow it, and sail with your jib and your mast. I have found that in a 35kt breeze an infusion mast is a respectable storm sail...

The original analysis is correct- the compression on the mast doubles if you support your mainsail by using a halyard that runs up the mast and is then secured at the bottom. Instead of thinking of the halyard and luff of the main independently, think of them as one continuous line. Negating the friction of the sheave at the mast head, the tension in the line would be equal throughout the length of the line. So, since the line travels up the mast and back down, there are essentially two falls. Pull on the downhaul with 400lb and that equates to 800lb of force on the axle of the mast head sheeve compressing the mast.

It is the same as having a block and tackle with a 2:1 purchase.

sm

That makes more sense to me now. Thanks.

So, in truly tough conditions, is it best to round up, drop the main, and then continue w jib vs trying to manage the mainsail?

Not as much fun though and not nearly as fast!

Here is some stuff I wrote here a while back. If you use the 'search feature" you will find more. Bon Chance. Chris

Have you ever seen a plane fly backwards? or stalled?
Sailing stalled out (falling in an airplane) with managed projected area (twist or travel) is the key to reducing the excess of wind power you are experiencing. Every notice how slow it is when the crew oversheets the jib, he is depowering/STALLING the sails.
Have you ever seen a plane fly backwards? Sailing stalled out with managed projected area is the key to reducing the excess of wind power you are experiencing.

I addition to getting your weight back, pull your main traveller (& jib) near the center of the boat with minimal twist(sheet in tight), steering ALMOST Dead Down Wind. The closer the mainsail is to the centerline the smaller the projected sail area to the wind reducing wind force and pitchpoling. This sail configuration puts the sail in a STALL, like an airplane falling through the air NEGATING lift.

For steering DDW try using the following (3)three indicators,
that kind of 'check and balance' each other.
First, the bow wind indicator.
Second, pay attention to the feel on helm.
You can maintain a very slight weather to neutral helm with the sails stalled out.
If the helm goes a lee you WILL eventually jibe,
so push the helm away from you to get back to neutral helm.
If the weather helm helm increases pull the stick to get back/close to neutral helm.
Finally, with the jib strapped in (stalled) watch which side the jib FAVORS, as it oscillates
back and forth (how it behaves) out of the corner of your eye, and react accordingly.
This is useful when it is raining so hard you can not see the bridal fly.

Looking behind you, often helps, as you can sheet in before the puff (dark water)
hits you. Its fun watching the other boats go over next to you, as they let OUT their sails.

when the sail stalls and the effective shape looks like a big fat wedge whose lee side isn't bending the wind near as much as you'd like, so the lift (component of the force at right angles to the apparent wind) is much less and the drag (component of the force parallel to the apparent wind) is excessive. The combination of the two is smaller and points aft, robbing the boat of the drive.

The above has kept me upright in registered 40kn wind in the "Round the Island" Florida race on a H20.

**************************************
So downwind try sheeting in the jib in the puffs to stall out.
To depower more travel in the main to reduce projected sail.
To depower more and stall out reduce twist(sheet in)
and enter the 'Stalled Out Zone'.
(CAUTION sailing stalled in winds under 20nt is SLOW)
**************************************

All the above goes out the window with nuclear, gusting shifting winds which arbo was talking about. The winds were very unpredictable because they were shifting so much. We traveled in but had a surprise gybe which nearly took us down. If your wind is from a constant direction, it would work but not when you have gusty shifty winds.

Our situation was also made worse because we had the tall rig (6' taller than stock). With the buoyant bows of the Supercat, I was more concerned about unexpected gybes than pitchpoling which we came really close to once. While the strategy worked with my boat does not mean it would work with every boat. Part of sailing is to know the characteristics of the vessel you are sailing. Our strategy worked because we made it to Key Largo with no flips, failures or broken parts.

Exactly, when the wind is blowing steadily from the same direction with a constant speed - more or less like the relative wind speed in an airplane - it becomes feasible to manage a larger sail area.

About mast compression, just see the picture:

Did anybody manage to retrieve the main sail on the water in heavy wind? I imagine it being very difficult to keep the boat head to the wind (heavy wind = high waves) sufficently. We can't furl the jib and the crew will be too busy to get the main down to hold the jib backwards.

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