Broaching - where is the edge?

[cwyckham]

Originally Posted by OldFrog75

No but I have obviously confused broaching with capsizing or knock downs. Thanks to everyone who has responded here and additional reading on my own I now understand that broaching does not necessarily result in capsizing.

In hindsight my original question probably should have been more along the lines of "how much heeling can a typical fin keel boat under 32' tolerate on a beam reach or close reach without capsizing (or knock downs?)."

I get it that broaching while running with the wind or on a broad reach is a more serious question and I greatly appreciate all the wonderful feedback I've gotten here.

I believe you also earlier said not in big seas. I would therefore say that the answer is dependent only pin your definition of knockdown. If knockdown means mast in the water, I think you'd need very violent and unusual wind changes to ever have that happen close reaching.

A others have explained, your weather helm well become so high at about 45 degrees of heel that the boat will take matters into its own hands and round up. You well have lost control, but the result is benign.

You should be reefing way before that anyways. Once the weather helm gets heavy, you've got the speed brake on. Reef to go faster with less stress on boat and crew

[cal40john]

Originally Posted by OldFrog75

In hindsight my original question probably should have been more along the lines of "how much heeling can a typical fin keel boat under 32' tolerate on a beam reach or close reach without capsizing (or knock downs?)."

Knockdown is more or less mast parallel to water.
Capsizing for a keelboat is tipping it over till the point where it will go inverted.

Most regular keelboats are not going to capsize until they are somewhere around 110 to 150 degrees (depending on design) rolled over, mast underwater. This does not happen just due to wind, you can only go to 90 degrees, knockdown, then the wind is no longer in the sails and the boat will start to right.

Keelboats have a lot of lead in the keel, the more you tip it the more the boat wants to come upright. Once you go past 90 degrees the lead starts becoming less effective as it comes in line on top of the boat. A boat with form stability will be stiffer at lower angles of heel, then becomes less effective. So once you are over closer to 90 degrees righting force will only be due to the keel.

So the answer your question, your boat will tolerate heeling right up to a knockdown and beyond . Most boats will become unbalanced and/or the rudder comes out of the water to the point that the boat will steer itself upwind and luff the sails long before you reach a knockdown. Long before any of these points the boat sails inefficiently and slower.

I used to crew on raceboats and have had broaches and knockdowns. Nothing broke, nothing bad happened. Cabin was a mess with everything thrown around. Everybody has to hang on and avoid getting hit by flailing boat parts. Broaches, especially with the spinnaker up can break lots of expensive stuff.

Someone I know broaching on a jibe in heavy wind with chute up, at around 3 minutes in. At around 5:20 they get overpowered and boat rounds up and luffs long before a complete knockdown:

https://www.youtube.com/watch?v=9vdoOdaBD4I

These guys said they had a knockdown at 2:48. As you can see they were nowhere near a knockdown and the boat was rounding up on its own:

https://www.youtube.com/watch?v=fwty14RIlbw

[denverd0n]

Originally Posted by daddle

Yet another reason it is wise for a sailor to bash about in small boats to learn about sailing. Can broach ten times a day and never upset the galley.

Exactly. If you really want to understand what it feels like when you're on the edge, then you have to spend some time sailing on the edge. Get a little sailing dinghy where half the fun is tipping it over, then go out and sail the heck out of it.

You will soon realize that in the bigger cruising boats you are talking about, you don't even get close to the edge in normal conditions.

[boatman61]

Originally Posted by cwyckham

I believe you also earlier said not in big seas. I would therefore say that the answer is dependent only pin your definition of knockdown. If knockdown means mast in the water, I think you'd need very violent and unusual wind changes to ever have that happen close reaching.

Newbies get caught out in places like the Canaries where you can be sailing along in bliss when the wind shifts and your suddenly in the acceleration zone with too much sail up...
those high volcanic islands do put the wind up the unwary first time there..

[Blue Crab]

Originally Posted by daddle

Yet another reason it is wise for a sailor to bash about in small boats to learn about sailing. Can broach ten times a day and never upset the galley.

This ought to be a sticky. This is how you learn to sail.

[cal40john]

Originally Posted by denverd0n

Exactly. If you really want to understand what it feels like when you're on the edge, then you have to spend some time sailing on the edge. Get a little sailing dinghy where half the fun is tipping it over, then go out and sail the heck out of it.

You will soon realize that in the bigger cruising boats you are talking about, you don't even get close to the edge in normal conditions.

While I agree that dinghy sailing is good for learning, I don't think it helps with the OP's question. I'm not sure what he thinks is going to go wrong with a keelboat when it leans way over, but it isn't lose stability before 90 degrees then eventually turn turtle unless you do something to prevent it.

What is the "edge" for a keelboat? Is it when the boat rounds ups? Is it when the angle of vanishing stability is reached? I'll give you broaching with a spinnaker up. You don't have to be over 90 degrees when the spin takes over and the spinnaker pole stuffs in the water and you're looking to see if/when the rig is coming down.

And dinghy sailing is more than for just learning, I do more dinghy, beach cat, windsurfing sailing than I do keelboat sailing.

Reminds me of a conversation I had with an instructor years ago. He was teaching MOB drills wrong for dinghies, insisted they pick up MOB on the leeward side. As person in charge of the teaching program I had to fix the problem. As a wet behind the ears college student in a college club run by students, I had to tell this guy with decades of experience he was doing it wrong. He explained to me that he was teaching it correctly for when they stopped sailing toys (dinghies) and moved on to real boats (keelboats). This was in a club with around 50 boats, only 2 of them keelboats.

I'm still sailing toys and I like it.

John

[daddle]

Dinghy sailing in heavy air will quickly teach a sailor about rudder effectiveness. Where the edge is. Where and why the rudder ceases to control and what happens next. Why the boat is actually being steered by the sail trim. Doing this in a cruising boat, intentionally, is silly.

To the point: the edge is where the unstabilizing forces from over trimmed sails exceeds the corrective forces obtainable from the foils.

[mrohr]

Originally Posted by goboatingnow

I would argue the opposite. Modern underwater designs are more hydrodynamically stable and spade rudders provide more control. Modern designs can surf without loosing control and broaching.

Dave

A little knowledge can be a dangerous thing. The OP is asking :where is the edge? I submit that any cruiser who is doing what is suggested above in the big steep seas I mentioned is truly on the knife edge. Yeah, those top racing gorillas with their professional helmsmen surf their sleds in these conditions but even these well funded daredevils would not not argue that this endeavor is not without great peril to both man and machine.

[OldFrog75]

Originally Posted by cal40john

Knockdown is more or less mast parallel to water.

Someone I know broaching on a jibe in heavy wind with chute up, at around 3 minutes in. At around 5:20 they get overpowered and boat rounds up and luffs long before a complete knockdown:

These guys said they had a knockdown at 2:48. As you can see they were nowhere near a knockdown and the boat was rounding up on its own:

Any idea what the wind speed was in these two videos?

[rtbates]

Originally Posted by Ocean Girl

I had a boat that had the ships bell mounted so perfectly, the bell would chime when it was time to reef.
In calmseas and steady winds your boat will probably head up into the wind before the broach. Plus her weather helm will get too much. Remember, at a certsin degree heel, the boat will just start dumping the wind and you will slow down.
My husband loves to try to touch the spreaders to the water.. me, I like a cool 20 degrees.

A racer would be the best at this question, they always are pushing a boat to her limits.

Erika

Funny you mention a bell. Our Cape Dory's bell, mounted on the port interior bulkhead will ring when the lee rail is under and we get a puff..Just about right...Our narrow beam full keel CD sails best with the lee rail JUST under. Close hauled, of course!

[ozskipper]

Originally Posted by OldFrog75

Any idea what the wind speed was in these two videos?

In video two the Skipper mentions something about 45 knots. Given that it is a very kicka$$ day and video never truly represents a seas state. He could be right.

[ozskipper]

Originally Posted by OldFrog75

I believe it when I hear the greatest fear of new sailors is broaching and everyone needs to know how to avoid it. But heeling in a steady wind can be fun and exillerating if the crew and helmsman can tolerate the excitement. Question is, where is the edge and what is the point of no return?

When I was a lot younger and much more stupid the only way to find out how fast you could go through a turn without the rear tires breaking loose was to go faster and faster until the rear tires did in fact break loose. But I'm older now and I don't want to test the limits of heeling without broaching by utilizing empirical evidence.

I understand all boats are different and generalizations are hard but generally speaking in steady winds with relatively calm seas less than 2 feet, how much heeling can a modern fin keel sailboat (circa 2000 or later) under 32' tolerate without broaching? Is it 45 degrees? Is it safe to sail with the leeward rail in the water? If the leeward rail is in the water is it safe to head up to depower the sails or is easing the traveller and/or main the only best option?

Don't get me wrong. I don't intend to take it to the edge but if I know where the edge is, then it is easier to stay calm if/when things get dicey.

This question is in the context of recreational cruising - not racing.

Broaching is far from my biggest fear. 99% of broaches are harmless and do nothing more than stir up a lot of adrenaline. Start talking accidental jibes, Dragging anchors with a lee shore, hitting a container, MOB, Hatch diving- now your talking about my fears :- D

[goboatingnow]

Originally Posted by mrohr

A little knowledge can be a dangerous thing. The OP is asking :where is the edge? I submit that any cruiser who is doing what is suggested above in the big steep seas I mentioned is truly on the knife edge. Yeah, those top racing gorillas with their professional helmsmen surf their sleds in these conditions but even these well funded daredevils would not not argue that this endeavor is not without great peril to both man and machine.

Many production boats surf just fine

[Jd1]

Originally Posted by Capt Phil

it was all fun and we didn't lose anyone important overboard.

How many unimportant crew did you loose overboard ?

[goboatingnow]

Originally Posted by ozskipper

Broaching is far from my biggest fear. 99% of broaches are harmless and do nothing more than stir up a lot of adrenaline. Start talking accidental jibes, Dragging anchors with a lee shore, hitting a container, MOB, Hatch diving- now your talking about my fears :- D

Accidental gybes even , the other are things your wife does to you when she's not thinking.