# Definition of Knockdown?



## CapnSantiago (Jul 17, 2007)

I've read/heard of knock downs but never experienced one...unless: 

I was sailing Lake Texoma on my Islander 30 this weekend (as usual) which had some quirky winds from the east/southeast. Heading north hugging the east shore where the channel is I was on a starboard fore-beam reach with winds about 15 (less than 20 as there were no whitecaps) a gust almost dipped the rail but not quite and I instictively headed up to take advantage of the blow with full main and genoa flying. The wind strengthened and dipped the rail to the enthusiasm of my First Mate Barbara (we had only buried the rail once before on this boat...unlike the regular routine on the J24 we used to sail). The boat then dipped further and white water on the rail turned to green water on the rail to white water over the coaming and into the cockpit dowsing my aft portside stern mounted speaker. Vanishing Point got a little squirrely feeling momentarily as though she was trying to spin on her side to starboard as everything starboard side in the cabin crashed accross the cabin sole. This lasted all of 5 seconds or less as I corrected to port and she stood back up and sailed on as if nothing had happened on a steady beam. As Barb and I continued to feel our quickened pulses and laugh in amazement listening to the garbled water soaked speaker we noted the bottom 12" of foresail was also wet and had obviously dipped.

So, does this qualify as a knockdown? I've heard a knockdown is when the mast hits the water (though I'm not sure if this is meant literally) and I know the spreaders didn't touch. Also, was the side spin feeling the start of what I've heard as a broach? I want to put this one in the log book, especially if it qualifies as a knockdown (not something you're suppose to strive for I suppose...but worthy of documentation).


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## scottyt (Jul 19, 2008)

to me a knock down is at least a spreader getting wet.

a broach is rudder out of the water, and boat turning up real hard and fast, often getting the spreaders wet again


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## AllThumbs (Jul 12, 2008)

I always thought a broach is where the bow digs in and the stern passes the keel. I believe it includes a knockdown, but doesn't always start with one.


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## CapnSantiago (Jul 17, 2007)

Thanks...I guess I'll have to settle for green water over the rail and white water over the coaming...neither of which that I care to experience again anytime soon. I can't imagine being over far enough the spreaders or mast touch the water. I could foresee people in the water with that experience.

Looking forward to more input/definitions regarding a broach...


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## johnshasteen (Aug 9, 2002)

You're right, that's a green water thriller. Paloma has never been completely knocked down - the closest we've ever come was at the begining of a Force 10 storm in Gulf. When the storm hit us full abeam (according to the Coast Guard a cold from moving at 35mph, packing internal winds of 50-60), it knocked us from a 10-15 degree heel to port, through a huge arch all the way over to burying the starboard handrails in the water and filling the sails with water, filling the cockpit with water and drenching the interior. She quickly rounded up into the wind, shaking hundreds of gallons of water over the entire boat. But, even that wasn't a true knock down - just the begining of a 36 hour adventure.


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## Siamese (May 9, 2007)

I wonder if there's an official definition. My personal definition would require the top of the mast to get wet, but I guess I'd settle for the spreaders.


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## smackdaddy (Aug 13, 2008)

Santiago - I'd call that a sweet BFS. Stolen and catalogued.


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## Faster (Sep 13, 2005)

I'd define a knockdown as any time the boat gets rolled to near 90deg heel - whether by a gust or wind or a large sea, or as the aftermath of a broach when sailing downwind. Generally by then your fins are nearly out or out of the water, no longer effective and, indeed, the spreaders may well be wet.

I'd call a broach the result of a spinnaker overpowering the boat, causing the rudder to cavitate resulting in a severe round up, with a resulting knockdown if the wind is still in the kite. "Thumb's" definition of a broach sounds closer to a pitchpole to me....

Any of which ought to qualify for a BFS!!


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## smackdaddy (Aug 13, 2008)

Faster said:


> Any of which ought to qualify for a BFS!!


Only if you get her back up and keep going with the racing pulse, huge guffaw, and rebel yell.

Otherwise it's an SAR. And those suck.


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## Boasun (Feb 10, 2007)

AllThumbs said:


> I always thought a broach is where the bow digs in and the stern passes the keel. I believe it includes a knockdown, but doesn't always start with one.


That is pitch poling. A broach is when you have boarding seas coming over your broadside.

Have had a knockdown in a Catalina 25. The spreader was soaked royally in the water. But she came back up. One of the reasons I don't drink on a boat anymore.


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## sailortjk1 (Dec 20, 2005)

Knockdown = Mast parallel with the water; Also known as a Knockaroach 
(I make stuff up as I go)


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## Omatako (Sep 14, 2003)

We had two knock-downs on our trip from the US to New Zealand in 2007, both in the same storm.

The first we were lying a-hull at 3:00am and were hit beam-on by a broken wave. The force was enough to knock cabinetry off the walls down below. My wife went into freefall across our cabin and landed in the join between the deck and the hull so we figure that we went to at least a horizontal mast.

The second was in the following dawn when we were motoring out of the storm and we drove up the side of a wave at an angle and the top of the wave broke against the side of the boat when we were about half way up.

In this event the mast went well below horizontal because we were in the cockpit and the mast was in the trough of the wave with the wind anemometer underwater. I watched that happen and it was confirmed by the wind indicator being stuck on 74 knots when the boat stood up (don't know why) and it only worked for another few days before packing it in altogether.

So I guess a knock-down for me is a roll-over that get's arrested at the last moment and the boat stands up again. I don't know why we didn't role the second time but I know that I was ready to take a really deep breath. 

When I was young and foolish and raced boats, we had many spinnaker broaches and to me they don't qualify as a knock-down. I guess everyone has a different view and none are actually wrong - it's what it means to you that counts.


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## chandlerman (Apr 26, 2008)

I don't have a copy handy, but I want to say that in the post-race survey of the 1979 Fastnet Race, they defined a knock-down as "mast past 90 degrees."

I've also done the microburst broach like the OP describes where a strong gust off a thunderstorm knocked us over to where the rudder was out of the water and we took water into the cockpit. It behaved pretty much like a spinnaker broach except that it seemed to go on longer since the jib didn't collapse as quickly. 

I think that wind-driven knock-downs are also not in a class with wave-driven knockdowns just due to the difference in force--the top of a wave weighs tens of thousands of pounds and transfers momentum much more effectively than air.

Having grown up in Dallas and experienced the local weather, though, I can definitely believe that you'd get those sorts of gusts off a storm on Texhoma--I know that I've had my share of gust-induced (as opposed to young-and-stupid-induced) knockdowns and turtling with sunfish, dinghies and hobie cats on Texhoma, Possum Kingdom, and various other lakes in that part of the world.


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## CapnSantiago (Jul 17, 2007)

Thanks for the responses/input/stories. It was just this last Sunday so I'm still feeling the experience. 

OK, BFS I believe to be Big Frickin Sail...COOL...I had the racing pulse and the guffaw, but kept the Rebel Yell internal to myself (our wide eyed look at each other said it all though) we looked around and there was only one sailboat in proximity to us. We wondered if they saw it and what they were thinking/saying if they did. But SAR?


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## smackdaddy (Aug 13, 2008)

Omatako - I have tee'd up BFS for you. That sounds like a great story that needs to be told!!!

Santi - SAR is search and rescue. Never a good day.


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## RanAweigh (Jan 16, 2009)

Boasun said:


> One of the reasons I don't drink on a boat anymore.


cuz ya spilled it?


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## Boasun (Feb 10, 2007)

RanAweigh said:


> cuz ya spilled it?


No spilling of the Hot Buttered Rum in a thermos. 
But the three of us on board saw a spinnaker wrap on another boat and that should screamed wind shift. But we were celebrating a race win and laughed at the spinnaker wrap... Then that wind shift hit us. Over we went and the spreader touched the water.
this happened when most of you were mere twinkles in your daddy's eye. 
So when you are out there sailing and you see a spinnaker wrap or a Genny on another boat that is a bit up wind of you, then you should be prepared for that wind shift. We were close hauled and the shift put the wind broadside to us. Over we went.
Note: pay attention to the weather because wind sheers will do the same.

That HBR sure was good that fine Saturday afternoon in the summer of 1976


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## smackdaddy (Aug 13, 2008)

Here's to booze in sippy cups and twinkling in your daddy's eye! (That's got to be a toast.)


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## AllThumbs (Jul 12, 2008)

The closest I have come to knockdown is about 45 degrees. Plenty to upset everything in the cabin, but not enough to fill the cockpit with water. I have only sailed 1.5 seasons mind you. I find at 45 degrees, you are standing on the side of the lee side cockpit seating. I don't need to go past that, but I am sure I will.

Eric


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## Cruisingdad (Jul 21, 2006)

My definition is at or about 90 degrees. 

- CD


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## Valiente (Jun 16, 2006)

Yes, I would agree with that. Control surfaces like keel and rudder have to be clear of the water...you can't help yourself much until the righting kicks in. It needn't be 90 degrees, but it's a lot more than the 45 degrees you see in a broach.

Broach=skid
Knockdown=falling over
Capsize=tumbling
Pitchpole=tumbling end over end.

It's the last one that really scares me. Reading what happened to the Smeatons on _Tzu Hang _in the '50s very nearly put me off ocean sailing.


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## smackdaddy (Aug 13, 2008)

Wow Val, I'd never read about the Smeetons and the Tzu Hang before. Holy crap!!!

Gotta drop a brief write up I found into the BFS thread. Thanks for the heads-up.


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## imagine2frolic (Aug 7, 2008)

The Smeatons, not once, but twice in nearly the same location. No EPIRB in those days, so a sailor patched their boat up, and sailed for port with what ever sail they could get up.......*i2f*


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## Valiente (Jun 16, 2006)

And Beryl swam back to the boat (now without a coach house or, I believe, masts, with a broken arm!

Basically, reading about these two is like reading that the two toughest people in the world met and fell in love.


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## Faster (Sep 13, 2005)

Valiente said:


> And Beryl swam back to the boat (now without a coach house or, I believe, masts, with a broken arm!
> 
> Basically, reading about these two is like reading that the two toughest people in the world met and fell in love.


Absolutely... for anyone into "ocean survival" tales, their books are required reading. Of interest, too, is that John Guzzwell (of Trekka fame) was along for the ride on one of those trips.


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## imagine2frolic (Aug 7, 2008)

For me this is what is done when the sh&% hits the fan. You pick yourself up, and get to work. Isabelle Autissier rolled, and came up with a stump of a mast in the Southern Ocean. She rigged the boat, and sailed onto Australia turning down rescue. Intestinal fortitude against the odds that just has to be admired........*i2f*


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## EO32 (Jan 7, 2008)

When sailing my SolCat 18, flying a hull and getting knocked down is part of the sport. I have avoided pitchpoleing which is not very fun.


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## painkiller (Dec 20, 2006)

My first broach occurred on my friend's boat soon after I learned how to sail. We had the spinnaker up in a building breeze. I don't know if the masthead touched the water or not because I was too busy hanging vertically from the windward winch. When we finally popped back up, we noticed that we were the only boat out.


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## smackdaddy (Aug 13, 2008)

The only boat out - AND flying your spin. Yeah baby!


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## freddyray (Aug 11, 2008)

sold a day sailor about two weeks or so ago. The couple who bought it were very new to sailing and my wife and I took them for a test sail. We were in 18-20 mph winds sailing along with already a good heel all four of us sitting windward. My wife and I saw the gust coming and grabbed ahold of something. They did not and slid down both of them to the leeward side. He was rather a big chap so his extra weight and the fact we were in a gust dipped the rail and we started taking it water. I had dumped the main, but in his slide down to reach for something he had grabbed the main so it would not release. All the while I am hollering for him to let go of the main. He finally did and she righted herself with about 6 inches of water in the cockpit. This was right after he had asked me how many times had I turned it over and I had told him never. Well they laughed about it and bought the boat. Closest I want to come to it.


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## CharlieCobra (May 23, 2006)

I've put Oh Joy's sticks in the water once, once was enough.


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## railsunderinca (Nov 20, 2006)

*Pitch pole* - ass over tea kettle "Endo" summersault. Usually the result of following seas and winds. Trimarans are notorious for this maneuver due to the fact they don't broach well. They will either pitch pole or cartwheel.

*Broach* - bow digs in swinging boat to right or left depending on angle of approach and what side wind is hitting you, which, if you're coming down off a wave or swell, will often result in a knockdown due to momentum of boat, wind and swell coming from behind.

"V" shape of bow mandates that boat WILL swing hard left or right depending on initial angle of attack as bow begins to dig in. (yeah, yeah, port/starboard for you nautical term freaks). Like putting your hand out the window of the family car when you were a kid and tilting it to go up or down. In the boat's case, left or right.

*Knockdown* - can be full (mast slap) or partial (boom dip with water over center skylight, hatch, cabin, etc.)

*Tutrle* - Boat goes belly's up. Not good. Good point for swing, vs. fixed keel folks.

Rails awash are fun. Lifelines awash are exciting. Cabin awash is pucker factor "extreme". E-ticket ride guaranteed to put smile on your face should boat regain its composure and you survive.

Play safe


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