As a card-carrying coward with a well-developed fear of storms at sea, I have long taken a deep interest in accounts of heavy weather at sea, and particularly stories of storm damage and abandonment.
While reading these accounts always scares the crap out of me, I still do so on the theory that the more I know about bad stuff that happens to other sailors offshore in heavy weather, the more likely it is that Phyllis and I can equip ourselves with the knowledge and gear to avoid the same fate.
This has been a learning project that has covered some fifty years, starting with reading the first edition of Heavy Weather Sailing, on through Miles and Beryl Smeaton’s account of two roll-overs while attempting to round Cape Horn, to the present day, where the internet makes educating (and scaring) myself ever easier.
A Common Theme
One thing that really jumps out at me from all this reading is that the vast majority of these storm disaster accounts have the following in common:
- The boat was rolled over or pitch-poled.
- Said roll-over almost always results in abandonment, particularly these days when calling for help is far easier than it once was.
- Pretty much every crew stated afterward that everything seemed under control, often for many hours or even days of heavy weather, until a “rogue wave” caused disaster.
A Core Problem
It’s this last point that I’m going to write about in this chapter, since I think the key to avoiding the same fate lies there.
John-
I very much appreciate your thoughts on this- I find your rational, conservative approach to be calming when considering a storm at sea, and inspires confidence in my future-self’s ability to skipper a boat offshore…someday. It’s articles like these that keep me coming back to AAC, keep up the good work!
Hi Chris,
Thanks for the kind words. I think the key to feeling confident is having recognized reality and then planned to deal with it, so glad the piece worked that way for you.
Hi John,
Very nice article thank you for that.
So if you are offshore, and it blows gale force 8 steady for a day or two, you would deploy JSD, sit and relax?
Thank you!
Hey John,
Interesting article with lots of sage advice. But I wanted to mention there are two types of extreme wave events. First, are the big waves described statistically by the edges of probability distributions and the second is a true rogue/freak wave not described statistically. You are completely correct in describing the statistical expectation of waves that are bigger than a given Hsig. But this statistical approach to describing a given wave state depends on the usually justified assumption that the waves are growing from wind growth only with minimal wave-wave interaction. In the open ocean, with relatively flat bathymetry, and small current gradients, the underlying assumptions of this statistical wave description are well justified. You also correctly describe the chance of encountering one of these statistically expected larger waves.
The second type of extremely large waves, are the more accurately described “rogue/freak waves”. These are waves that occur that are not described by the typical probability distribution that you summarize well (like the 1:1000 waves). These occur in locations with un-even bathymetry (like sandbars or sea-mounts), geometrical wave-focusing in basins, or when current gradients exist.
In these areas, the waves interact less nicely (technically non-linearly). These unusual situations are believed to lead to cases where waves constructively interfere (add together) to create a very large wave, and appear to remain in this newly-constructed shape. This is of course different than the statistically described large waves where wave-trains pass through each other without exchanging energy. These waves are not comprehensively understood, as we have very few ocean measurements of them, but there are laboratory tests that have been able to replicate the formation of very large waves in frequencies that can not be described statistically (i.e., exactly these freak waves). I will try to pull up a paper to help summarize modern “freak” wave research.
But one semi-side-note, the ocean is dispersive. This means that the waves of different wavelengths travel at different speeds. The speed of a wave crest increases linearly with wavelength, therefore the largest waves that avoid breaking from being too steep, will have a longer wavelength, and therefore travel faster than the other waves. This is likely why when a large, statistically-expected wave is experienced, they affect the vessel so much more: more velocity, and therefore more imparted momentum. Dispersion also explains why the first noticeable effect of a distant hurricane is the presence swells; swells out-run the other smaller waves, arriving first.
But this does not impact your article much, as you (likely correctly) describe that sailors may be wise to consider switching to a capsize-resistant storm method early on, and not to try to analyze the storm for big wave and therefore capsize probability. A freak wave, can not develop from benign conditions: they are created during stormy conditions where already large waves meet, in locations where they are constrained or modified by some factor, and become even bigger.
Cheers
Conor (PhD, Marine Physics, University of Miami)
Conor, I’ve read a few of the papers you’re talking about, and now I need to go track them down again. Good reading, for a physicist.
I’m reasonably confident in saying that:
1. “Rogue” waves (i.e. waves that do not nicely obey the usual 2nd-order partial differential equations, but instead invoke more complex nonlinear behaviours such as exchanging energy between interfering systems so as to become phase-locked for some time) do exist, they have been observed in the wild, and they have been numerically & empirically simulated in labs.
And
2. The waves sailors are talking about when they say “it was all fine until the rogue wave hit and everything went to hell” are, in virtually all cases, *NOT* those waves. Rather, they are (as John described) the extreme tail of a statistical distribution describing perfectly ordinary waves and their constructive/destructive interactions, and are therefore a normal, expected thing that you will encounter in gale-force or worse conditions.
Bottom line, I think John’s right that fretting about (or blaming) the “rogue” wave is unproductive in this context. Understanding what “significant wave height” means, with respect to the probability of encountering larger or smaller stuff, is important. Understanding the conditions that make it appropriate to switch strategies, and recognizing when that point is approaching before you actually cross it, is important.
Hi Matt and Connor,
Interesting about waves outside the statistical norms. I did mention bottom contour and current and can verify from experience that both will produce some truly fearsome waves in even benign conditions.
Anyway, as long as I got over the point that most yacht capsizes could have been avoided with the right gear deployed soon enough, all is good. So glad that worked for both of you.
Hey John/Matt
Yes, I think the article is pretty justified in saying that it is better to prepare for waves that are bigger than the waves one is currently experiencing. If it was me, I would probably not say “There are no rogue waves”, but I get the point that likely there are many stories of people who incorrectly claim a freak wave him them, instead of saying a large, expected wave him them. As usual, another great AAC article!
cheers
Conor
Forgot to link this:
It is an article by a captain that I did an atlantic crossing with that describes a rollover in a westsail 32 south of Australia.
http://www.westsail.org/Resources/Documents/Articles/Mike%20JohnsDismasting.pdf
and a 2nd-cup-of-coffee reading on rogue waves:
https://www.dropbox.com/sh/rp51j080dy0kxz9/AACaag6iCuZebTCTpN3CPx88a?dl=0
Hi Conor,
Interesting article on the Westsail 32 roll over. Lots of wisdom, although that said I would caution readers from taking too much of it aboard since much of it is based on the understandable, but fundamentally flawed, thinking of the time. Or to put it another way. I would near guarantee that if they had had a JSD deployed or had been truly heaved to, they would not have been rolled. The writer talks of heaving-to with a storm jib. That’s not being truly heaved to, which almost always requires sail area aft of the mast, but rather fore reaching.
More here” https://www.morganscloud.com/2013/06/01/when-heaving-to-is-dangerous/
And what to do about it here: https://www.morganscloud.com/2013/06/01/stopping-wave-strikes-while-heaved-to/
Hi Conor,
My use of “No Rogue Waves” was a device to make the point, rather than any statement of scientific fact or opinion.
And thanks for the kind words.
Hi John.
I can’t add anything here, but I can give my view on a couple of issues. You say “As a card carrying coward with a well-developed fear of storms at sea…”. This is partly humour, of course. It’s also a simple and interesting topic. Someone who is about to jump out of a plane should be to some extent frightened, no matter how many times it has been repeated. Some degree of fear sharpens our awareness and gives us the ability to make it a lot safer. The fact is that jumping out of a plane will always be lethally dangerous. We still do it because we accept the statistical risk of death, and more importantly, because we have the illusion that our personal skills and attentiveness is so good that our personal risk is way lower. The latter part is silly, but more important: Not being frightened isn’t brave, it’s stupid.
When cruising the oceans, the risk of lethal danger is extremely much lower than when jumping out of a plane, and the most probable lethal danger isn’t storms but falling overboard in normal weather, even close to shore. Still, a sailor who has experienced extreme weather will always fear it deeply. Again, any other attitude is just stupid.
About the “rogue wave” topic, I’ve often thought that it sounds like a bad excuse for lacking awareness or just accepting a risk. A digression to illustrate a different type of attitude: My friend Are Wiig who recently retired from third place the Golden Globe Race after being rolled over in the roaring forties and loosing his mast says nothing about “rogue wave”. He just said that he’d been having really bad weather for three days and that it had calmed down a lot to just 40ish knots, so he found it worth a try to stop to repair his wind steering, again, as he was exhausted after so long time hand steering with no sleep. While working on it an “especially big wave” lifted the boat, turned it upside down and dropped it free falling many meters. He knew that these waves were around, but had to hope it didn’t hit. It still did. He didn’t have a JSD…. he didn’t complain and he didn’t ask for help, but closed the holes and cracks in the boat, tended to his wounds (he cracked the main hatch with his head), rigged a jury rig and sailed to Cape Town. He also wants to participate next time…
Especially big waves, predictable or not, hurricanes, and similar should be seen as dangers similar to ground getting closer at an alarming speed. If we know we are falling, we can’t pretend that it doesn’t matter so much because the ground might miss us. If we’re at sea, those dangers do mostly miss us, but when they don’t, they have the same effect.
As mentioned in other contexts, when the consequences are not acceptable, like death, our risk tolerance must move way down. 1% risk of rain means I won’t bring an umbrella. I can tolerate being a bit wet. If I point an imaginary gun at my head and know that 99 out of its 100 bullet chambers are empty, I’m gonna be extremely scared!
Hi Stein,
I followed Wiig’s situation as it unfolded. As you say, he took a risk he understood but his luck was out. He didn’t make excuses or whine, he just dealt with it. Truly admirable.
And I totally agree with your thoughts on fear. Show me a person who is not afraid of the sea and I will show you a damned fool who is a menace to themselves and the people that go to sea with them.
Hello
an interesting article, but you allude to your preparation strategies without spelling out how you prepare. I think many readers would like hear your take on specific anti-capsize preparation.
thanks>
DB//
Hi db,
We have a whole online book on that, of which this is just one chapter: https://www.morganscloud.com/category/storm-tactics/online-book-heavy-weather/
Jordan gives a good account of people in capsizes believing everything is O.K. until it happened and the resulting belief in a “rogue wave”. He says pretty much the same thing you state. The waves are steep enough that a boat can’t sail down them but rather falls off them generating huge forces that can roll or flatten the boat (from a fall on its side). The only solution is to cause the boat to slow down and best to use a mechanism that spans a few wave lengths so it can’t get pulled out of the water and can continue to act as a break – hence his design for the Jordan Series Drogue (JSD).
Having spent a nail biting watch helming a 53′ 18 ton boat accelerating from 9 to 14 knots in seconds surfing down 20′ waves in a Force 8 gale, I have an appreciation for how one of these could do significant damage if the boat were to turn or dig in its nose. In this instance, we were going down the east coast parallel to the Gulf Stream but in a southbound eddy with the winds on our tail and under bare poles except for about 2 square metres of unfurled Genoa to keep the boat tracking downwind (and on course). We were moving (perpendicularly) through a shipping lane at the time or we’d have heaved to or deployed the JSD (which we would have if it got any worse (winds were forecast to moderate back down to force 6 in the am)). The boat handled it beautifully and tracked in full control but it was clear that we all felt a hell of a lot better knowing we could deploy the JSD if things got any worse.
Hi brent,
A lot of this article came from Jordan’s work.
Interesting story about helming down wind in very heavy weather. I too have done this, most notably in an old tiller steered one toner (class not weight) in the gulf steam in storm force winds some 35 years ago. We had a full race crew of skilled helmspersons aboard, so we pulled it off, but one helming mistake could have ended very badly. As it was we put the spreaders in the water at least once.
Point being that although skilled helming can make running off work in surprisingly nasty weather, it’s a high risk strategy and totally dependant on the skill of the drivers and the steering gear holding together.
Interesting thoughts and thanks for them. Having spent many years at sea as skipper on trawlers and tugs, it was “easy” enough to ride out bad weather by ‘dodge and lay’, not least as we always had a great big diesel engine to keep us straight into the waves, ahead or astern [less so in the latter]. Having moved to sailing, I would appreciate your view on the multitude of opinions on drogues v streaming warps. In a recent online piece related to the Golden Globe, RKJ was adamantly in favour of streaming warps rather than a drogue, not least due to the difficulties, dangers and time needed to retrieve one. I wasn’t sure whether he was advocating streaming heavy warps with anything attached as singles or in a loop?? Many thanks. Jeremy
Hi Jeremy,
You will find my thoughts on strategies and several survival accounts, in detail, in the rest of this online book: https://www.morganscloud.com/category/storm-tactics/online-book-heavy-weather/
As to trailing warps. While I have huge respect for RKJ, the science does not support his opinion. Bottom line, warps will not exert enough drag to prevent disaster in a truly huge breaking wave.
Or to put it another way, if it’s too easy to retrieve, it does not exert enough drag to do the job properly.
The science is pretty solid on that: http://www.jordanseriesdrogue.com/pdf/droguecoastguardreport.pdf
That said, I’m sure warps will work most of the time, so I guess it comes down to your risk tolerance. Me? I have a JSD.
Also, I don’t think RKJ has tried a JSD. Therefore I’m more comfortable with Trevor Robinson’s opinion on the matter: https://www.morganscloud.com/2017/05/19/battle-testing-a-jordan-designed-series-drogue/
There are ways to make retrieval easier: https://www.morganscloud.com/2013/06/01/jordan-series-drogue-retrieval/
Another excellent article, breaking down hundreds of years of sailors lore into a rational approach.
Hi Richard,
Thanks very much. Makes it all worth while.
Wow, great article and great comments!
As a new to off-shore sailor, I need to hear this. It sounds like my reefing strategy. If I think I should put in a reef, (or my wife does), put it in before things get stupid. So putting in a 3rd reef around 30 kts should be a clue to drop a JSD! More to learn from Colin in the spring!
I have a question – you reference the wave height as a percentage of the boats length (as does the article you referenced) – but the article also points out that the risk of end-over pitch poling is much less and the risk is mostly associated with being hit beam on.
My question is then why is the boat length relevant? Why not beam width? Is it because the average length to beam ratios are relatively similar?
It certainly makes much more sense thinking width rather than length. The idea that my 30ft boat could be rolled by a 10ft wave, and most certainly rolled by a 20ft breaking wave seems more intuitive given she’s only 12ft wide.
Hi Mark,
Good question. If memory serves, when the original work was done at the Wolfson Unit they did quote beam, not length. I guess they changed just to simplify things.
In 2002 I was returning from Hobart to Sydney and after a stop at Eden , headed north with a forecast of 25 knts. Around 12 we were getting 35 and it looked like getting worse, so we avoided the foul ground between Montague Island and the coast by going further out to sea.
This put us into a 5 knot adverse current and the Southerly built into an East Cost low which stayed over the 50 knots the B&G max. I was steering my 45 ft 20 t steel cruising yacht
Delta Wing which was an excellent sea boat.
By now the seas were extremely steep and I worried about falling off a wave.
Suddenly a wave came at right angle to the wave train and it picked up the yacht and threw it about 20 ft.
As it landed the pressure on my hands on the wheel became so painful I had to let go the wheel and she slewed to port as the next wave in the normal train picked her up sideways and I looked down around 30 ft and it was almost straight down.ie the wave was close to dumping. Having studied the excellent books on the 98 Hobart I headed back towards shore and once out of the current they were merely very large swells.
Had I stayed out in the current I would have either fallen off a wave or it would have dumped on the deck.
I would not have liked to be sitting there with a drogue .
The Hobart books show conclusively that the best tactic for the yachts was to continue sailing into the storm. This meant that they were out of the storm earlier whereas the yachts that ran with it stayed in the storm longer, as it worsened.
Hi Bill,
Thanks for an excellent analysis, and I totally agree that the best tactic was to get out of the current ASAP. A 5 knot current against 50 knots is a boat killer no matter what you do in the way of drogues.
That said, do keep in mind that the recommendation to keep sailing was situation specific to the S to H race and assumed a full on race crew with expert helmspeople aboard. Most AAC readers are short handed cruisers, who would not be able physically to keep sailing for long:
https://www.morganscloud.com/2013/06/01/heavy-weather-strategy-goals/
So for us cruisers, as I say in the post, the key strategy is not to enter an area of adverse currents when the wind could get over 25 knots. A much easier goal to achieve today with more accurate weather forecast and reasonable priced sat phone data, than it was in 2002.
Hi John,
You make a very good point that almost all of these incidents are likely not due to rogue waves and simply waves that should be expected with any real length of exposure. To me, this lines up reasonably well with casual observation too. When you are out on a sporty day where it is still fun, you get the bigger waves where you are glad that isn’t the norm but you also get an occasional one which makes you go yikes. Another eye-opening experience is to deal with the wind over tide at a bar crossing where in 100′, you can go from scary breaking waves to a pleasant day by simply ducking in and out of the current, it really shows just how important it is which I often don’t appreciate offshore.
I am also a wimp and enjoy reading about different accounts of survival and disaster. Most of my offshore work was done when I was an invincible age but I increasingly look at the incredible spread of conditions where boats have gotten in trouble and think yikes. Some of it is clearly the boat, some the crew, some probability but also there is definitely an element of windspeed and less-so wave height being poor indicators of actually how bad conditions are. Thankfully I don’t have the experience of ever being in a situation where survival was a real question but the occasional worse wave, helming mistake or similar has made me realize how much closer we were than I realized.
It also seems to me that our use of terms like gale has become problematic in some places. For example, tonight’s forecast where I am is 15-20 gusts to 35 knots (cold front coming through) and there is a gale warning up with the synopsis stating that there will be a period of “pre-frontal gale force winds”. To me, that either suggests that the forecast should be higher or that the definition of sustained winds versus gusts has changed.
Eric
Hi Eric,
Lots of good points highlighting how important it is to really think about the conditions and our reaction to them.
And I too have noticed that both the weather forecasts and general usage these days seem to be throwing terms like gale and storm around when in fact all that is really happening is a short lived cold front with a bit of gusting.
I have written about this several times in the last few years:
https://www.morganscloud.com/2015/07/11/dont-abuse-admiral-beaufort/
https://www.morganscloud.com/2009/02/01/radio-fear/
Hi John, I think of the readers/contributors of AAC to be in three categories: 1) Experienced sailors who can speak from VAST experience, 2) Sailors who know exactly what you are talking about but haven’t had their lives flash before their eyes, and, 3), me.
I am for intents and purposes, someone who has not been out of the mouth of the mighty Columbia River, but is someone who has not only dreams, but has a mind and strength of will to fulfill his dream to become the sailor who fits 1) aforementioned above.
With the disclaimer that my experience is limited to reading books and AAC, I want to pose the simple question: Does the Pardey bridle system make all of this a potentially non-issue as the slick will, in theory of course, eliminate the breaking waves (and thus the configuration of the wave becomes irrelevant)?
I have timidly brought up the Pardey bridle/slick in prior posts and would really, really love to hear the voice of experience resound again. Please advise, you sailors of the seven seas.
Steve Broom
Hi Steve,
I have written on the Pardy Bridle and our variation on the idea here: https://www.morganscloud.com/2013/06/01/stopping-wave-strikes-while-heaved-to/
That said, the point of this article is that having a storm strategy and gear only works if we deploy it in time. Which storm strategy to use is a different discussion, and a complex one, that we have a whole online book on: https://www.morganscloud.com/category/storm-tactics/online-book-heavy-weather/
The underling issue is today’s fixed keel sailboats and their propensity to trip over their own keels. I sail a one hundred year old design by Ralph Middleton Munroe, his Presto 36, a true centerboarder, with no stub keel. With its board raised she simply doesn’t have a problem with knockdown from breaking waves, Even with the board partially raised, a side strike from a breaking wave simply pushes her sideways, like the surf dories of old.
Hi Nelms,
While I agree that a lifting keel can provide a lot of safety in just the way you say, once waves get really big and breaking it’s not, I think, a no capsize guarantee. Here’s an example:https://www.morganscloud.com/2014/05/22/loss-of-yacht-tao/. I also know of an Ovni that was capsized near Panama.
As I say in the above piece, does this conclusively prove that a lifting keel boat can be capsized by a breaking wave? No. But given the research on breaking wave capsize with the conclusion that any boat can be capsized, I, for one, would carry a JSD.
Hi John,
There is the overall safety which you emphasize, but I would imagine (and I feel lucky to just imagine) that there is something to be said for the comfort level a JSD might achieve. It seems likely that a boat without much of a keel, would slip and slide around in a manner which could be quite fatiguing over time, perhaps even a danger to those inside the vessel.
My best, Dick Stevenson, s/v Alchemy
Hi Dick,
While I can see that one could reasonable assume that, generally lifting keel internal ballasted boats like the Ovni and Boreal are actually more comfortable in a wave train, not less, than deeper keeled boats. The reasons are complex, and probably beyond my ability to explain scientifically, but none the less it’s true.
I have personal experience of this with a shallow draft centre board boat, albeit with a stub keel, that I did a lot of ocean racing on. Pull the board up, and she got a lot more comfortable.
And there are few things more uncomfortable than a very heavily ballasted deep keel racing boat (personal experience again).
That said, I do think that a JSD might make lifting keel boats even more comfortable, and certainly safer.
I would have believed the no rogue wave idea except that during Hurricane Florence I was watching the live stream from the camera at the Frying Pan Shoals and twice in less than an hour I very clearly saw waves much larger than the current wave train moving at right angles to it. Do the people who say there are no rogue waves just lack observational data?
Hi Marcus,
The title was only to make the point that being rolled by one of these is not just bad luck.
You will find in the article that I have clearly stated that very large waves are out there and that we should plan for them.
In regards to heavy weather sailing it seems to me that what we have is this:
what we’ve read,
what we’ve heard and
what we’ve experienced regarding anything in life and heavy weather sailing.
My experience with Huge seas took place in May of 2016 sailing from New Zealand to Fiji. I had found a Belgian girl to crew who was not a sailor but could cook, and didn’t get seasick!
It was a difficult and tiresome 8day sail as we were on a beam reach almost the whole way. On the 7th day the wind and waves kept building. It was a mostly clear and sunny day and since we were getting close to Fiji the water and air temperatures were warming. I was sailing with a double reefed main only on my Rhumb line at about 60 degrees to wind and waves, in about 25-35knts of wind. The autopilot had quit several days before and the boat was being steered flawlessly by my backup Hydrovane which works best in high winds. It is called a Crush or Crunch Zone. The waves continued to get bigger and having sailed up and over these waves I sensed tha I needed more speed so I turned on my Yanmar diesel and was motor sailing at 6.5 Knots up and over these waves which keep getting bigger and bigger, finally reaching 10-12 meters. As an aside, I decided at this time that instead of panicking, I thought these waves were beautiful! Magnificent slow moving and mostly well behaved monsters! It was my incredible luck that my 60 degree angle to the waves was PERFECT! My Catalina 42 would work its way up a wave and I could look over the Lee side into a canyon! I realized that by moving forward at 6.5 knots, the momentum carried me up and over and prevented me from rolling down these waves!
At the top, I could see for miles and noticed several “Rogue” waves in the distance, which I am convinced are waves within the statistical variation of the waves I was experiencing. Two of these waves that I sailed up and over had breaking heads, which I would say felt and looked like a four foot wave at the beach. One of them broke over my Bimini and cascaded through the cockpit. My reaction was to lay down flat and allow the wave to roll through. These waves lasted about 2-3 hours before diminishing, my Belgian crewmate slept through the whole ordeal! We reached Suva the next day.
My take aways:
ORIENTATION TO THE WAVES IS CRITICAL!!!
Sailing down wind during these huge seas may have resulted in broaching (loss of control of steering) or pitchpoling! Which seems to lead to most calamities!
Sailing on the beam is asking for a knockdown regardless of boat speed!
Sailing or motoring directly into the waves is equally foolish as the possibility of falling back down a huge wave is unimaginable!
SAILING OR MOTORING AT AN OBLIQUE ANGLE TO THE WAVES IS THE BEST OPTION! 70-40 degrees to wind and waves seems optimal!
You can sail upwind or downwind, depending on your Rhumbline but upwind seems to be safer as the back sides of waves are less steep.
And don’t forget the that you must have boat speed! 5-7knots minimum if possible!
In waves like I experienced, heaving to or lying to a paranchor or drogue seems dangerous and foolish, considering the forces involved on line and tackle!
Keep the boat moving and under control is the best option from what I learned.
I was very lucky that day!
Since that day I have sailed to New Calidonia, Australia and circumnavigated Tasmania. My beloved boat is moored in Bay of Islands, New Zealand and I am joining her soon!
I’m sure there are many of you armchair or dockbound sailors that may find fault with my story and reasoning, but if I can add an idea or option to this woefully monstrous, irrational and scary topic, I will be glad.
Fair Winds,
Capn Michael
Hi Michael,
I certainly agree that fore-reaching (what you were doing) can work well. In fact I survived the worst storm I have experienced in just the same way: https://www.morganscloud.com/2013/06/01/lee-shores/
That said, experience and science has shown that you would also have been just fine with a series drogue as designed by Don Jordan. And the advantage of that option is you would not have had to steer or be reliant on you engine, rig, and steering gear holding together. Also, given that you were holding a double reefed main, what you were experiencing was probably around gale Force 8 at most. While there’s no way to know for sure, I think, and experience has shown, that if the wind had built to storm force or above, you would have been far safer with a series drogue.
More here: https://www.morganscloud.com/2018/10/13/just-get-a-series-drogue-designed-by-don-jordan-dammit/
The chunk of water that can pick you up and drop you down is not a rogue wave but a freak incident caused by counter acting forces in that specific location in a certain timeframe.
For those of us who have been in the situation where we look around us in awe and comment, “whew, glad we weren’t over there”, active avoidance comes into play.
If the conditions have rendered the crew incapable of active, alert sailing I would chose to set the boat up to sheer off the wind in the direction of diminishing pressure and rest in the cockpit with half an ear open. Most often there is a forewarning.
Rogue waves are not bad luck, getting caught by one is…
“Don’t tie me down.”
Following the condensed action in the GGR has brought to light some interesting reflections concerning the multiple dismastings. Looking forward to hearing the skippers renditions.
Hi Rikki,
While there are many that share your thoughts, I’m not one of them. See the next chapter for why, including a story of when active avoidance did not go well for me: https://www.morganscloud.com/2018/10/13/just-get-a-series-drogue-designed-by-don-jordan-dammit/
I also see the track record in the Golden Globe rather differently: I would call it a graphic demonstration of the failure of strategies other than the series drogue. Again, see the above linked chapter.
There is a new study (Dec 2018) publish in Journal of Fluid Mechanic’s, sharing the results of their study to replicate the Draupner Wave. This wave was laser measured at 25.6M in a 12M significant wave height conditions from an oil rig in the North Sea. At 2.13x SWH, it is on the upper edge of the maximum expected wave size. But as I understand it, what was really unique about this wave was not the height, but how steep the face was. Traditional thinking would have predicted a wave that steep could not exist, it would have broken and collapsed at a much lower height. Using a specialized wave tank they were able to replicate the wave for the first time by varying crossing angles (they recreated it at 120 degree cross). A summary of their conclusions from the abstract is:
“Using this capability, we recreate a wave of equal and greater steepness to the Draupner event with an equivalent surface elevation time series and demonstrate the directional conditions necessary for it to exist. In doing so, we also show that the breaking mechanism can be fundamentally altered in crossing seas: breaking no longer acts to limit amplitude in the same way, but results in upward, jet-like behaviour. We thus propose an additional fundamental process to be taken into account when seeking explanation of rogue waves in highly directional seas such as at Draupner: directional breaking for crossing seas.”
Link to the abstract and a free download of full paper can be found here:
https://www.cambridge.org/core/journals/journal-of-fluid-mechanics/article/laboratory-recreation-of-the-draupner-wave-and-the-role-of-breaking-in-crossing-seas/65EA3294DAFD97A50C8046140B45F759
The paper is quite technical. I don’t have a solid enough understanding of wave science to understand all the details, but find it interesting none the less, and thought others may as well.
Doesn’t change your overall conclusions of prepare early, but it is a new quantitative data set, accurately measured from a real world “rogue wave”, with laboratory confirmation of those measurements, and conclusions around the mechanic’s that lead to the formation, all conducted by expert wave scientists in a controlled environment. It provides a new perspective on what might be happening out there at any given moment of time that you aren’t expecting, and in fact was previously believed to be impossible. All the more reason to prepare early.
Hi Robert,
Thanks very much for what sounds like a very interesting and useful heads up about a change the understanding of large waves. I will take a look, although I suspect that the science will be more than a bit beyond me.
Hi Robert.
Interesting text. I’m also not competent enough to interpret the scientific language properly, but I already knew about the wave incidence since it was observed and measured from a Norwegian oil platform 24 years ago. Marintech at the university of technology in Trondheim did a much discussed study on it, without finding anything that could be used to understand it, but crossing wave trains were mentioned.
Some issues I find interesting in this report:
– The “wave-averaged free surface” goes down under a wave train, while with a crossing wave train, it goes up, increasing the measured wave top elevation, making it able to reach higher relative to a fixed installation like an oil platform, but not so with a boat.
– “The structural loads on the Draupner platform were much smaller than would be expected for such a large (non-crossing) wave.” This tells me that the wave itself probably didn’t move fast or far but was rather the momentary manifestation of wave interference/collision.
– “Breaking no longer acts to limit amplitude in the same way, but results in upward, jet-like behaviour.“ This confirms the impression of the previous point. This isn’t really a wave but a localised happening.
– “ A combination of a large winter depression and short duration ‘Arctic bomb’.” The arctic Atlantic (Southern Norway, but in the winter definitely arctic) has weather that is close to impossible most places on the planet. (As a side note: Very cold air is much heavier, thus contains accordingly much more energy. That makes a gale into an entirely (!) different beast. Yes, I’ve been shaken, and stirred. 🙂 Not recommendable…)
My not competent evaluations would be:
This wave seems to fit exactly what I observed in much smaller scale, wading and swimming at the north tip of Denmark 45ish years ago. (Described in a long post further up here.) These mini “Freak waves” seemed 3 or 4 times the height of the normal waves, but were not going anywhere. They just jumped straight up and disappeared. Apparently no power. I see it as the collision between two energy pulses. They cancel each other into not much energy, but some of it isn’t aligned and makes a splash, kinda like throwing a water balloon on a wall…
A 26 meter version of this type of wave would probably not be a nice thing to encounter, but its destructive force might be way less than it seems. More importantly, its seems very unlikely that normal long distance cruisers sail in conditions where a this type of wave on this scale is likely to appear.
So, my conclusion: I can’t see that I need to prepare for or fear this type of wave. I will, however, hope not to encounter one in real life….
Hi Stein,
Not that I’m qualified to judge, but your analysis make sense to me.
I particularly agree with your last point that those of us that treat the seasons with respect in our sailing, and are sensible about getting and analyzing weather forecasts, should not let the possible existence of such a wave generated by extreme circumstances bother us over much.
This site includes a video of the wave they created.
https://arstechnica.com/science/2019/01/oxford-scientists-successfully-recreated-a-famous-rogue-wave-in-the-lab/
The sea is getting wilder, which gives import to this discussion.
“Extreme ocean winds and wave heights are increasing around the globe”*
Is it length or displacement that effects capsize resistance?
E.g. do you think that two 36 footers of 9 and 12 tonnes (loaded cruising weight) would be equally susceptible to capsize?
Would both be improved by stretching to 42′ (with commensurately reduced beam and hull-draft)? Thus stretched, would the heavier boat have the advantage?
*https://www.sciencedaily.com/releases/2019/04/190425143540.htm
Hi PD,
My understanding is that size is the primary variable that affects capsize resistance, but there are a lot of variables here, including mast weight, so I think that attempting to parse things to that level is probably beyond what the science will support. The bottom line is that, as I say in the article, it does not take a huge storm to produce a wave that can capsize any of the boats you mention, so better to have a JSD and deploy it in time than even worry about variables that small.
Hi PD,
I agree with Johns thoughts, but since I’m a nerdy nit pick, I have a couple of additional detail notions:
As I understand your post, I would like to split your questions up a bit into these:
1. Will a boat be less vulnerable to capsize if it is lengthened while keeping all other proportions unchanged. Thus, a longer but relatively narrower boat, that is probably a bit heavier, but relative to its length, is lighter and floats higher.
2. Will a given boat be less vulnerable to capsize if its weight was increased without changing any other parameter?
I can’t answer these questions with indisputable facts, but my strong conviction is that question 1 must be answered by a clear “Yes!” If the boat was not only lengthened, but evenly scaled up to a bigger boat, with the weight also scaled up, the improvement would most likely be even greater.
For question 2, I need to split it into two scenarios, to give an answer I think is true: If the boat just gets heavier in a uniform manner, so it floats deeper but the stability is the same, the answer must be “NO!” Such a change would in my opinion make the boat clearly more vulnerable to capsize.
If all the weight increase was in the keel, thus increasing the boat stability, the answer is probably “yes”, it would have a bit more resistance to capsize by waves, but perhaps not always and not with any level of weight increase. A certain boat design fits a certain weight. Some designs are fairly tolerant to weight changes, others quickly get major problems.
Designers put a lot of attention to where the waterline is. The hull is shaped with that line as one of the most important factors. In general, changing a boat in its fundamental properties, like weight, is not a straight forward issue. However, improving stability by removing weight aloft, like changing to a carbon mast and getting rid of rubbish in the rigging, has far superior effect compared to adding weight to the keel.
When I say “rubbish in the rigging”, that’s harsh words to get the attention towards all the stuff we put up there and how much it influences our boats’ properties. Just weigh one of the halyards you have. Do you really use all of them? That stainless steel antenna platform at the mast head, have you checked what it does to your stability? I can promise that if you get a qualified engineer to look at it, you won’t like the answers.
An example: In the eighties, the Norwegian King was making a serious effort for the IOR One Ton World Championship, which at the time was only second to The Americas Cup in competitive big boat racing. They were looking at every little detail of every aspect. Two of the crew were people I sailed with often, so I got much interesting knowledge there. One detail that caught public attention was that they decided to sail without the wind sensors at the mast head. The reason was that the unit and bracket was about 400 grams and the cable was almost 2 kilos. To compensate for the stability loss, they needed to add 21 kilos in the keel. Both of these would mean lots of lost speed in pitching motion. So, nothing at the mast head but a super light old fashioned Windex. The campaign resulted in victory. Obviously not only because of this choice, but the numbers are interesting…
One more rant: In the conditions when capsize is an issue, windage aloft is also a major issue. The mentioned “rubbish” plus several furled headsails make for a problem the original GGR sailors didn’t have. I know that furling headsails are very practical, but I still have a love/hate relationship with them. I think many cruising boats would be far better with fewer of them.
Hi Stein,
Interesting thoughts, but I have to say that in my view the summary is “it depends”. For example, yes making the rig lighter increases static stability, but it also decreases dynamic stability and so actually increases the chances of capsize in some scenarios.
But to me the key thing is that if we put every factor that could increase capsize resistance into a say a 40′ boat what do we get? Probably a boat that might be able to withstand a wave without capsize that is say one or two meters bigger than a boat that was not so optimized. So sure, we have made the boat safer, but we have not, in any way, solved the problem and we still need to carry a JSD and deploy it in time.
So, for this reason, I get nervous when I hear debates about how to make a boat more capsize resistance because very often the fundamental fact that all boats will be capsized by the wrong breaking wave gets lost in the discussion.
All of that said, as you know I’m all for clean rigs and sea worthy stable boats.
Hi John,
Again, I agree with every word.
My post above was initially meant to address an idea I’ve frequently heard, that a heavier boat is safer, just as a function of its weight, which I feel is usually quite the opposite.
I then went on to discuss details of the issues in a way that might indicate that I believe in optimising the boat to avoid big wave capsize. I don’t. I really think most boats can be improved quite dramatically by looking at the right details. That’s fascinating and can be great for everyday boating life, but those improvements are almost irrelevant to avoiding capsize by waves. Sorry for the distraction. My theoretical detail focus does indeed risk removing the attention from the real issue:
Any boat, no matter how well designed, prepared and handled, can be capsized by the right circumstances. We all need a strategy suited for the boat, crew and situation to overcome that problem. For any realistic long distance cruiser scenario, the core of that strategy should be a JSD.
Looks like the waves are getting bigger with time:
https://tinyurl.com/yyjqnfl8
“Their study found that the largest rises have occurred in the Southern Ocean and also that the magnitude of extreme wind and wave events (those in the 90th percentile) have increased significantly.” and
“Extreme wind and waves
Their work reveals that these waves, and the winds that generate them, are increasing in magnitude and have been doing so for the last 30 years on a global scale. Furthermore, the study shows that extreme wave conditions are increasing even more rapidly – with the largest increases occurring in the Southern Ocean. Indeed, extreme winds in the Southern Ocean have increased by approximately 5.4 km/h or 8% over the past 30 years. Extreme waves in this region have increased in height by 30 cm or 5%. In general, the study found that winds are increasing at a faster rate than wave height.”
Hi Colin,
Thanks for the link. Yes, I read that too. Very sobering. There is no question in my mind that the ocean is becoming even less forgiving than it used to be.
https://www.quantamagazine.org/the-grand-unified-theory-of-rogue-waves-20200205/?utm_source=pocket-newtab
Very interesting. Some people are surprised when I comment that my high school math and physics course have found application in sailing, and math and physics continue to contribute to our knowledge of the sea.
Hi John,
Terrific analysis. I recall reading something that discussed the treachery of cross-seas causing enormous unexpected energies. Cross seas causing potential for highly irregular and large seas that must be planned for and accommodated. I would guess these are experienced in the High Latitudes as the low pressure systems rotate around. This would make the backside of low pressure systems particularly dangerous, just when skipper and crew are tired, of course? I wonder if it makes sense to weave this concept into the chapter somehow?
Whitall
Hi John,
That’s a whole different, although valuable, discussion and is really more about heavy weather avoidance. My purpose with this chapter was just to make the point that very large waves that will capsize a boat without a JSD do occur often and that claiming bad luck when it happens is simple wrong so I don’t think I want to dilute that by adding a whole bunch of stuff about cross-seas, at least here. Point being that a full gale that has been blowing for a day can produce a wave big enough to capsize the average yacht even without a wind shift. Also, there is some debate about the real affects of cross seas in deep water. For example Don Jordan was not a fan of that theory.
Hi John
I just returned this week from a passage from Nova Scotia to Portugal aboard a well-found 56 ft boat, following a great circle route that took us up near Newfoundland, across the southeast corner of the Grand Banks and well north of the Azores. All went well due in large measure to good weather information from Predict Wind. About half way between Newfoundland and the Azores, well out in very deep waters, we had more than a day’s worth of east setting current running as much as two knots with patches of chattering little waves, small whitecaps and very distinct transition lines just like you see in inshore tidal currents. This was no doubt a far reaching branch of the Gulf Stream. The wind was light and the favourable lift was welcome, but a moderate easterly gale against that current would have set up a fearsome sea with “rogue waves” a distinct possibility. This reinforces your message that potentially dangerous wind against current situations can be encountered in unexpected times and places, not just in the Gulf Stream and similar well known risk areas. Be prepared for surprises!
Hi Wilson,
A very good point. The ocean races I did as navigator have left me with a lifelong interest in ocean currents so we have always had a calibrated speedo (log) and accurate swung compass. Using that combination to compare against the GPS has shown us that most of the ocean has at least some current and a lot of places have a lot more than one would expect. I fear that these days many cruisers are just blindly following the GPS and so have no idea how much current they are in.
Hello John, all,
Thank you for this nice article and the nice discussions that followed.
There is a current article in Physical Review Letters (PRL 132, 154101) which describes the departure from a gaussian distribution for waves, in other words, rogue waves. The summary article is open access: https://physics.aps.org/articles/v17/61 and the pre-print is also open access: https://arxiv.org/abs/2310.01841. The article is a bit technical. I should also note that it seems these data were collected during mildly stormy conditions (no actual windspeed given, but significant wave height was ~4m), so if there is a dependence on severity of the storm it would not be registered here.
I found it interesting that they actually observe the non linear behavior of the waves. What they found was that this predominantly occurred in what they named “young waves”, that were still being actively driven by the wind, while the “old waves” showed a very gaussian behavior.
So in an actively wind driven sea, the occurrence of extra large waves is higher than statistically expected from a gaussian model. It seems a good reason to be extra careful deploying the storm tactics early rather than waiting it out?
Cheers,
Maurik
Also see an article in The Maritime Executive ‘Rogue Waves are Much More Common Than Anyone Thought’; https://maritime-executive.com/editorials/rogue-waves-are-much-more-common-than-anyone-thought . The same content with additional explanation. Shows that I need more practice in recognizing how front patterns and their evolution, influence what I will see locally. After reading (again) the book here Online Book: Weather Reception and Analysis, I am now trying to predict what I see in the marina, with what the Ocean Prediction Center puts out every 6 hours. Using my new found Barometer tool for the iPad, Marine Barograph, described at https://www.starpath.com/marinebarometer/about.htm. Pretty amazing that I now have a view of what’s coming up with just these simple tools, and only takes moments. Off to also start gathering wave data to see if I can correlate front movement out in the Eastern Pacific with wave height.
Hi Glenn,
Good to hear you are taking a proactive approach to this. That said, while correlating forecasts with what we see is a very good idea I think that, even today, we must remain aware that the conditions capable of capsizing a yacht can be local to quite small areas that likely won’t show on forecast products. For example a current of as little as .25 of a knot running against the wind and wave train can tip the balance between safe and dangerous.
So we must remain committed to being aware of the actual conditions and be willing to deploy a JSD even if synoptic and forecast models don’t support the decision.
Hi Maurik,
Your conclusion makes sense to me and agrees with what I have observed out there over the years and the point of the above article: very large waves that can capsize a yacht can happen in conditions that don’t seem that bad. And yes, as I say in the article above, the rule should be deploy if there is any doubt at all about the conditions, and sooner than the uninformed think, particularly if running off.
Good to see that we are getting more and more science to support that.
That said, I still think we should move away from using the term “rogue wave” because it implies rarity which enables bad choices and claims of bad luck when things go wrong.
I will try and break some time loose to read the article.