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Drogues on Trimarans

D/T-9 Trimaran, Shuttleworth

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SHUTLWTHD/T-9

Trimaran, Shuttleworth

60' x 40' x 10 Tons

12 Knotted Warps (300' each)

Force 12 Conditions

 

File D/T-9, derived from an article by Richard B. Wilson, appearing in the October 1991 issue of SAIL MAGAZINE - Vessel name Great American (ex-Livery Dole IV, ex-Travacrest Seaway) hailing port Boston, MA, maxi ocean racing trimaran designed by John Shuttleworth, LOA 60' x Beam 40' x Draft 11' (3' board up) x 10 Tons - Drags: 12 knotted warps, 300' each (3/4" and 5/8" nylon) - Deployed in a 940 milibar storm in deep water 400 miles west of Cape Horn with sustained winds of 70 knots and breaking seas of 50' - Vessel capsized on 22 November 1990 despite the 12 long warps - Crew of two were rescued by the M/V New Zealand Pacific.

On 22 October 1990 Rich Wilson and Cape Horn veteran Steve Pettengill set sail on the 60-ft. maxi ocean racing trimaran Great American determined to break the 76-day San Francisco to Boston record set in 1853 by the clipper Northern Light. Apart from wanting to beat the record, it was also Rich Wilson's goal to heighten public awareness of the activities of the American Lung Association and to prove the viability of corporate sponsorship in sailing. Wilson is a severe asthmatic.

Sailing out of San Francisco Bay Wilson and Pettengill put "pedal to the metal" and tried to imagine their opponent, Northern Light, beginning to trail behind. Having records of Northern Light's daily runs, they had their imaginary opponent in view, so to speak, trailing behind all the way down the coast of California and then Mexico. In skirting hurricanes Trudy and Vance off Mexico, however, the lead changed hands a few times as the ghost of the 200-ft., three-masted clipper ship would overtake the trimaran, only to be later overtaken herself. Once past the equator, Wilson and Pettengill began bashing full bore into the southeast trade winds. The going was rough and took a heavy toll in equipment failures. After passing Pitcairn Island they began to line up their approach to Cape Horn - and "the mother of all storms."

It began as a low system that "exploded" (to quote the words of meteorologist Bob Rice) into a 940 milibar storm, with Great American's number written all over it. Approximately 600 miles from Cape Horn the storm said hello to Wilson and Pettengill when the trimaran broached, tripped on her big daggerboard, and Wilson was thrown violently out of his bunk. The two dazed men found that they had to raise Great American's huge daggerboard all the way up to improve steering and avoid tripping on it.

Steve Pettengill then let out five knotted warps, 300' each, slowing the boat down a little. On the next day the boat broached again with the five warps in tow. But she side-slipped smoothly - raising the board had definitely helped. Pettengill added three more 300' long knotted warps. On Wednesday morning, 21 November, the boat's barograph tracer hit rock bottom. Four additional knotted warps were then added, making a total of twelve (12) to bring the speed back down to 9 knots in 70-knot winds and 50-foot seas.

On Thanksgiving morning, some 400 miles west of Cape Horn, a graybeard swept over the entire boat (this trimaran is 60 feet long and 40 feet wide!) carrying away the two wind generators. Great American then rushed down another steep mountain. The combined drag of the twelve knotted warps were not enough to keep her properly aligned. She slewed to starboard, probably dug the port ama, heeled, and capsized. The two men, fortunately OK, immediately donned their immersion suits, activated the 406 MHz EPIRB, and resigned themselves to the business of survival. As they were sorting out the debris in the inverted main hull, "the grandfather of all waves wrenched the water-laden trimaran out of the water, spun her, and slammed her violently back down, upright again." (Quoting from Wilson's article in SAIL).

So, Great American was right side up again! But the mast and the rigging were in pieces on deck and trailing in the water. The cockpit was awash and the main hull looked like a submarine, with the winches at sea level. Everything was in shambles. Everything had broken free down below. They wondered whether they would have been better off if they had remained upside down. Somehow, in the freezing cold, they managed to sort things out and get a little hot nourishment. Meanwhile, Scott Air Force Base in Illinois had received a "hit" from the EPIRB. Additionally the ARGOS, which had gone off when the second wave righted the boat, had alerted a base in France, which alerted Atlantic Rescue. AMVER (automated merchant vessel emergency routing) then found the nearest ship to be the New Zealand Pacific. In a feat of brilliant maneuvering, Captain Dave Watt brought his 62,000 ton ship - the world's largest refrigerated container carrier - alongside the awash Great American at 3:30 am in the dark. With the 815-foot ship rolling severely, Captain Watt coordinated the throttles and bow thrusters with such precision that Rich Wilson and Steve Pettengill were able to step onto the rope ladders hung down from the cliff-like side of the ship. They were then taken inside, cared for, and taken to Vlissingen, Holland.

Three years later, Rich Wilson and his new crew mate, Bill Biewenga, set out again from San Francisco. This time Wilson accomplished his goal. On April 7, 1993, Great American II finally arrived in Boston, 69 days and 20 hours out of San Francisco, beating Northern Light's record by six days. Wilson is currently head of Ocean Challenge, an educational institution dedicated to linking classrooms all over the world with ongoing adventures. Ocean Challenge has an interesting web site that readers may wish to explore: www.sitesalive.com

Drogues on Monohulls

D/M-5 Monohull, Tayana

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HUDYD/M-5

Monohull, Tayana

37' x 11 Tons, Full Keel & Cutaway Forefoot

Warps, Submerged Dinghy, Etc.

Force 11-12 Conditions

 

File D/M-5, obtained from Patton S. King, Houston, TX. - Vessel name Hudie, hailing port Houston, monohull, Tayana, designed by Robert Perry, LOA 37' x LWL 31' x Beam 11' 6" x Draft 5' 8" x 11 Tons - Full keel & cutaway forefoot - Drogue: Four warps, 250' each, with various items attached, including buckets, tarp, sail bags and submerged 8-ft. fiberglass dinghy - Deployed in hurricane Juan (October '85) in 100 fathoms of water about 130 miles SE of Galveston, with winds of 90 knots and seas of 30 ft. - Vessel yawed 40° and was eventually rolled full circle by a rogue wave, necessitating abandonment.

 

Hudie, a seakindly, canoe-stern Tayana 37 designed by Robert Perry, was on her way to Key West from Galveston in October 1985. To the east, a tropical depression had formed, which soon matured into a tropical storm, and was later upgraded to a full-fledged hurricane, named Juan by the National Hurricane Center in Miami. In the language of meteorologists, the term re-curvature refers to the shift in direction of the path of a hurricane, from a westerly to an easterly component of movement. Trying to predict when and where a hurricane is going to re-curve is the sort of thing that gives the men and women of the National Hurricane Center migraine headaches. Juan wasn't about to make things any easier. It was "all over the place," stalling and moving about erratically - playing a game of hide and seek with the forecasters.

Juan was only category 1 in stature, weak in so far as hurricanes go. In terms of damage, however, it would soon prove itself to be one of the worst storms in history. On October 28th, for instance, it forced 80 oil workers on 2 offshore rigs to take to life boats. On the 29th it sank an oil barge with 3 crewmen on board. On the 30th it was lashing the Louisiana coast for a second day, causing an estimated fifty deaths and one billion dollars damage. Governor Edwin Edwards said that Juan had done more damage to the state than any storm in history, and President Reagan had to declare the state of Louisiana a disaster area on November 2nd.

Meanwhile, back on Friday October 25th, Hudie was down to her last reef points, with the storm jib pulling like a bulldozer. The seas continued to build rapidly and on Saturday night she found herself engulfed within Juan's spiraling arms. Wind: Force 11-12. Hudie was running before 30-ft. seas now, averaging 6 knots on bare poles. With options narrowing the owner, Patton S. King, deployed a 9-ft. diameter BUORD on the fly, believing that it would stop the boat and pull the bow around, or at least partially around. No swivel was used. The rode consisted of 200 feet of 5/8" diameter nylon three strand, leading out of the port bow chock. The shock of the opening parachute was noted, along with extremely high tension in the rode. The boat's speed decreased from 6 knots to 3 knots. But Hudie did not round up into the wind. She didn't even come beam to the seas, but instead assumed a heading still downwind, with the seas on her quarter and with the rode leading off the bow, bent under the keel and trailing out astern.

We should digress briefly and ask the question as to why the 9-ft. diameter BUORD failed to exert some sort of a pull on the bow - make the boat stop, turn around and begin facing into the wind and seas. There are several possible answers.

In the first place, with nearly six feet of draft, a full keel and the forefoot cutaway, the Tayana 37's CE (center of wind effort) is well forward of her CLR (center of lateral resistance). A yacht like this won't even lie a-hull in hurricane force winds. Rather, she will tend to point downwind. For a sea anchor to countermand this tendency and actually pull the bow all the way around it would have to be larger - in the order of 15-18 feet in diameter.

In the second place, there is the matter of the torque associated with three strand rope under extreme dynamic loading. The chute was set on the fly, resulting in a significant shock when it opened. No swivel was used (not that it would have been able to rotate, initially) and extremely high tension was noted in the line. What happens to three strand rope when it is subjected to this sort of extreme loading? It torques. In trying to unlay, it will stiffens and rotate like an engine shaft, twisting the parachute shroud lines together into a thick lay and reducing the diameter at the mouth of the parachute. The sea anchor was too small to begin with, and with its mouth choked shut it could not possibly have pulled the bow of Hudie around into the seas.

At any rate, twenty minutes later the rode parted from chafe under the keel, and the boat resumed its 6-knot run down streaked mountains of water. Four warps, 250 ft. each, were then trailed over the stern, with various items attached, including buckets, 2 tarps, sail bags, an igloo ice box (full of ice and pop) and a submerged, 8 foot fiberglass dinghy. The combined drag was enough to slow Hudie down to 3 knots again. In fact, from 10 p.m. on Saturday, until 6 a.m. Sunday, the makeshift drogues improved the behavior of the boat to such an extent that in subsequent telephone conversations with Victor Shane, Patton S. King said that he could not have been happier with the way things were going.

At approximately 6 a.m. Sunday, however, it is thought that a rogue wave picked up Hudie, carried her sideways, broke and rolled her through 360° in about twelve seconds. Instantly cans, bottles, tables, utensils, floor boards and people were rolling around in total shambles inside - with broken glass everywhere. There was much evidence of roof damage, with extensive damage to the rigging, mast and spreaders. All the crew had sustained injuries, fortunately nothing major. They could not raise the Coast Guard, but a call to "any vessel" was soon answered by a couple of tugs and a commercial fishing boat. In the meantime they cut away all warps, started the engine, brought the bow around and began jogging into it.

By 3.30 p.m. Sunday afternoon the situation had become altogether untenable - all pumps clogged or broken, engine rapidly overheating and the boat being hammered by 25-ft. seas. When the F/V Gulf King appeared and agreed to take the crew aboard the decision was made to abandon ship. Soon all were safely aboard the Gulf King. Their last view of Hudie was seeing her get knocked down in the distance.

Drogues on Monohulls

D/M-2 Monohull, Bermuda Ketch

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JOSHUAD/M-2

Monohull, Bermuda Ketch

39' 6" x 13.4 Tons, Full Keel

Warps, Net and Pig Iron Drags

Force 10 Conditions


File D/M-2, derived from the writings of Bernard Moitessier - Vessel name Joshua, monohull, canoe-stern, center cockpit Bermuda Ketch build of steel, LOA 39' 6" x LWL 33' 9" x Beam 12' x Draft 5' 3' x 13.4 Tons - Full keel - Drogue: assorted drags used in concert, including 22 fathoms 4.5" hemp rope weighed down by 3 pigs of iron 40 lbs. each; 16 fathoms 3" hemp rope weighed down by two pigs of iron 40 lbs. each; 32 fathoms of 1.5" nylon rope trailing freely - Deployed while running before a mature storm in the high latitudes of the Southern Ocean with sustained winds of 50 knots and seas of 30 ft. - Joshua came near to pitchpoling several times and Moitessier elected to cut away all the drags.

 

Bernard Moitessier is undoubtedly one of the most extraordinary seamen that has ever lived. Fortunately he is an extraordinary writer as well. The critic Jonathan Raban once said, "I'd sooner read Moitessier than any other nautical writer alive." Indeed one never tires of reading Moitessier. He holds the imagination captive, from the first page to the last. Born in French Indo-China, Bernard's first odyssey was aboard his dilapidated junk, Marie Therese, which ran aground after a fifteen round - eighty five day - battle with a monsoon in the Indian Ocean. He then spent three years on the island of Mauritius, building Marie Therese II, which ran aground in the Antilles, after a long lonely Atlantic crossing. A few years later the resilient Moitessier had finished his book, Vagabond des Mers du Sud, and was in Chauffailles, France, getting married to "a little slip of a woman called Francoise" and overseeing the building of his new 39-ft. steel boat Joshua. In October 1963 he took Francoise "for a sail" on Joshua - across the Atlantic, through the Panama Canal, to the Galapagos and the South Pacific. The couple spent two happy, carefree years in Polynesia. In the winter of 1965 they "went sailing" again - Tahiti to Spain non-stop, via Cape Horn, 14,216 miles in 126 days.

It was on 13 December 1965 that Joshua ran into a heavy storm in the high latitudes of the Southern Ocean, mid-way between Tahiti and Cape Horn. Mindful of the experiences of Smeeton and Robinson, Moitessier deployed an array of drags to slow Joshua down - all told some 900 feet of heavy ropes weighed down by five 40-lb. iron pigs and a large heavy net used to load ships. Despite all the drag devices in tow Joshua came very close to sharing the fate of Tzu Hang - going end over end. As he struggled with the helm, Moitessier began to take stock of his situation and compare it with the experiences of other "Cape Horners," among them the renowned Argentinean singlehander Vito Dumas.

In the famous episode that followed we find Moitessier engaging the ghost of the Dumas in a debate, as it were. "But what was your secret, Vito Dumas.... You did it... and Legh II was a small boat... you carried sail, I believe you... but you couldn't have carried any sail in this kind of seas, don't spin me that yarn, for if you had carried any sail in these seas you would have been pitchpoled like Tzu Hang... and like Joshua, almost.... And yet, you covered the three oceans...." (Cape Horn, The Logical Route, Grafton Books, London 1987, by permission).

Moitessier then writes that he doesn't believe in ghosts, but could have sworn that he heard a voice - that of Dumas - telling him the answer. Once he had the answer he was aft, cutting away all drags and warps, allowing Joshua to run unimpeded on bare poles. He noticed an enormous change in her: "She had no longer anything in common with the wretched boat of the night before which had made me think of the little hunter trying to parry the blows of a gorilla, with his feet caught in the undergrowth." (Ibid.) Thereafter Moitessier adopted the technique of "putting down the helm," and Joshua began taking the seas more safely on the quarter. Later on in the storm, as they are sitting in the inside steering station, he explains the technique to his wife Francoise:

 

I'm running dead before the wind to keep the maximum speed on the boat and make sure that she answers on the helm when she has to. Now watch carefully, you see that wave coming up [behind]... I am still dead before... and just before the stern lifts I turn the wheel right down... You see... she heels over and veers to the right as she ought to... she is pushed forward and a little sideways... the moment the stern settles down again, just after the wave has passed I turn the wheel right over in the opposite direction to bring her back again stern on; this is the best moment because the rudder is deep in the water and very effective... you see... we are back dead before the wind, and the business starts all over again. (Ibid.)

Remarkably, Moitessier seems to be using his instincts to avoid pitchpole (see image in previous file). It must have been instinct because the phenomenon of orbital rotation was not well known at the time - nowhere in his writings does Moitessier refer to the orbital rotation of waves. Indeed, one can only infer that Moitessier must have been directed by some rare and spontaneous instinct peculiar to extraordinary seamen. By that, or by the ghost of Vito Dumas.

To fly dead straight down a wave face would have placed Joshua in the same head-over-heels predicament as Tzu Hang - the bow impaling itself in the approaching "current" in the trough as the stern was being hurled downwind by the motion at the crest. So, in maneuvering across the face of a wave (like a skier zig-zagging down a slope), Moitessier is in effect trying to cheat the pitchpole demon - trying to keep the bow from burying itself in the adjacent trough. To some extent the same principle is used by a surfer when he puts down his heel to "spin out" and disengage from the wave. Needless to say in order to execute this maneuver with precision over and over again in a storm, the helmsman of a sailboat would require the reflexes, the skill and the stamina of a Grand Prix driver, attributes that Moitessier no doubt possessed at that time, but hardly common to all sailors. Bear in mind also that Joshua was made of steel, had a canoe stern, a center cockpit, and an inside steering station where the helmsmen could concentrate on what he was doing, unaffected by the cold and the wet. It is interesting to note what the late Miles Smeeton had to say about this technique:

When Bernard Moitessier, that fine seaman, offers an opinion, it should be well considered, because he has twice sailed Joshua round Cape Horn... but his answer is not necessarily the right one for all yachts, any more than mine is, and it requires a superman to steer accurately like this through a dark night.... Even if his theory is correct for other yachts, tired men and irregular waves are apt to defy it. (Because The Horn Is There, Granada Publishing, London, 1984 & 1985, Appendix, by permission).

In 1982 Joshua was anchored in Cabo San Lucas, Mexico, when a tropical storm swept over the crowded anchorage. A large motorboat dragged down on Joshua, forcing her up on the beach, where numerous other yachts ended their careers as well. When the fiasco was over nothing remained of the famous boat other than her bare steel hull. Two brothers from Port Townsend, Washington bought the hull for $20 and spent two years rebuilding her, later selling her to a Seattle woman. The woman's dream of sailing Joshua around the world was rudely shattered by the indiscretion of her sailing partner - he turned out to be married. The French newspaper Voiles & Voliers heard about the affair and sent a photographer to Seattle. After the article - showing magnificent photographs of Joshua under sail - was published, a number of famous sailors banded together to form the Joshua Foundation. The French Maritime Museum then purchased the dear old boat, put it on a ship and took it to La Rochelle France, where she is on display today.

Drogues on Monohulls

D/M-1 Monohull, Bermuda Ketch

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HANGD/M-1

Monohull, Bermuda Ketch

46' x 12 Tons, Full Keel

Warp, 60 Fathoms 3" Hawser

Force 10 Conditions

 

File D/M-1, derived from the writings of Miles Smeeton - Vessel name Tzu Hang, hailing port Victoria, B.C., monohull, Bermuda Ketch, built in Hong Kong in 1938, LOA 46' x LWL 36' x Beam 11' 6" x Draft 7' x 12 Tons - Full keel - Drogue: Warp consisting of 360' x 3-inch manila hawser - Deployed while running before a storm in the high latitudes of the Southern Ocean with winds of 50 knots and seas of 30-40 ft. - The warp had little effect in preventing the pitchpole of Tzu Hang about 1000 miles from Cape Horn on 14 February 1957 - The yacht was sailed under jury rig to Chile, reaching Arauco Bay 36 days later.

 

This is probably the classic pitchpole in all of yachting history. All the major works on the subject of heavy weather tactics make mention of it. Adlard Coles refers to the 1957 pitchpole of Tzu Hang six times in Heavy Weather Sailing. In her two celebrated attempts to round Cape Horn, Tzu Hang was pitchpoled the first time and rolled the second. On the first attempt she was manned by a crew of three, owner Miles Smeeton, his wife Beryl, and the renowned singlehander John Guzzwell of Trekka fame, (Trekka Around The World, John Guzzwell, 1963).

Tzu Hang had been running before mature seas in the high latitudes (50° South) of the Southern Ocean, trailing 60 fathoms of 3-inch manila hawser. Unlike nylon, manila has the sponge-like quality of soaking up water and was at one time considered to be ideal for use as warps. In this case it was not very effective, for Miles Smeeton writes, "I watched the sixty fathoms of 3-inch hawser streaming behind. It didn't seem to be making a damn of difference, although I suppose that it was helping to keep her stern on to the seas. Sometimes I could see the end being carried forward in a big bight on the top of a wave." (Once Is Enough, Granada Publishing, London, 1984, by permission).

As the boat continued to run before the storm, one breaking wave did come aboard, but Tzu Hang showed little tendency to broach. She seemed to be doing quite well in fact. "It was a dangerous sea I knew, but I had no doubt that she would carry us safely through, and as one great wave after another rushed past us, I grew more and more confident." (Ibid.) At the time of the incident Beryl had just relieved Miles at the helm, and was steering the boat when a great wall of water approached from the stern, so wide that she couldn't see its flanks, so high and so steep that she knew Tzu Hang could not ride over it. Water was cascading down its face, like a waterfall. Miles was down below, reading a book: "As I read, there was a sudden, sickening sense of disaster. I felt a great lurch and heel, and a thunder of sound filled my ears. I was conscious, in a terrified moment, of being driven into the front and side of my bunk with tremendous force. At the same time there was a tearing cracking sound, as if Tzu Hang was being ripped apart, and water burst solidly, raging into the cabin. There was darkness, black darkness, and pressure, and a feeling of being buried in a debris of boards, and I fought wildly to get out, thinking Tzu Hang had already gone down. Then suddenly I was standing again, waist deep in water, and floorboards and cushions, mattresses and books, were sloshing in wild confusion around me." (Ibid.)

Beryl had been catapulted out of the cockpit and into the sea, landing some 30 yards to leeward. Miraculously she was able to swim toward the trailing wreckage of the mizzen mast. Her shoulder was badly injured and it took the combined strength of the two dazed men to pull her back on board. But the situation was now critical. Tzu Hang had received a near death blow. Both masts were gone and there was a gaping - six foot square - hole where the doghouse had been. The weather was not getting any better and she was taking on great amounts of water. She would no doubt have gone down, had it not been for the tenacity and sheer will power of her crew.

From the onset Beryl, although in great pain, did her best to provoke, spur and cheer the two men on into life-saving action. She was the driving force that kept resignation and despair at bay. And John "Hurricane" Guzzwell would soon put his resolve, his backbone and his skills as a carpenter to keep Tzu Hang afloat. He patched the hole in the deck. He sawed and hammered, laminated and improvised, putting back together the pieces that would - thirty six days later - bring Tzu Hang safely into Arauco Bay, Chile. What transpired in those thirty six days on the wastes of the Southern Ocean should serve as an important lesson to all sailors regarding the mindset that is so often crucial to survival itself, the lesson being this: Never give up.

What exactly happened? There is much speculation about the exact movement of the boat during the mishap. Miles Smeeton is certain that it was a somersault: "When she pitchpoled a very high and exceptionally steep wave hit her, considerably higher than she was long. It must have broken as she assumed an almost vertical position on its face. The movement was extremely violent and quick. There was no sensation of being in a dangerous position with disaster threatening. Disaster was suddenly there. Whether she had been 20° to it or her stern directly presented to it, or whether she had been running at 2 or 7 knots could, in this case, have made no difference. Her stern came up and just went on going with no hesitation at all right over the bow." (Because The Horn Is There, Granada Publishing, London 1986, by permission).

The reader may wish to compare Smeeton's observations with the statement of Joan Casanova (File S/T-1), who survived a similar wave in the Southern Ocean: "It was the type of a wave which pitchpoles yachts in these oceans, the type which every voyager sailing in the high latitudes of the Southern Ocean fears.... We want to stress here that no vessel, multihull, monohull or freighter, could have survived such a sea unless tethered with a long line from a sea anchor...."

Formula for Disaster
Formula for Disaster

 

Whereas a rising tide will lift a boat vertically by a force equal to her displacement (usually many tons), a steep wave will "lift" the same boat horizontally with equal displacement force (DF) at wave speed. Speed of molecular rotation is already about 7 knots on the crest of a 40-ft. wave (A). The decaying crest hurls tons of water at a wave speed of 20 knots at her transom (B). Force of gravity (C) drives the bow down into the adjacent trough where it is briefly met with 7 knots of reciprocal rotation coming from the opposite direction (D). Result: The stern goes flying right over the bow without any hesitation at all.

Miles Smeeton later wrote a short Postscript which may be the key to our understanding of the dynamics of pitchpole. This Postscript can be found on the last pages of Once Is Enough and includes the following remarks:

Since I wrote this book I have had a number of letters - mostly from well informed sources - on the reasons for Tzu Hang's two mishaps... the major cause was probably due to the orbital velocity of a big wave. I had never heard of this theory which is that, although the mass of water in a seaway, seen as a whole, is static, each particle of water moves in an orbit around the place which it would occupy at rest. If we were to throw some rubbish overboard so that it represents a particle of water on the surface, we would see it drawn back towards the approaching swell, lifted up, carried forward, and dumped in approximately its original position again; seen from the side it would trace an orbit against the background of sea and sky.

The important thing is the speed at which the water moves in this orbit, and for a forty-foot wave with a ten second period the speed is approximately seven knots. With seven knots on the top of the wave with the wind, and seven knots against the wind at the bottom, a forty-foot ship on the point of a forty-foot wave is subjected roughly to a seven knot push one way at her stern and a seven knot push the other way at her bow, a formidable overturning couple. A longer ship is already overcoming the push at her bow by the time her stern is subjected to the maximum thrust. The answer seems to be to keep forty-foot ships out of forty-foot seas, but if forced to run before them to tow long enough lines so that there is an effective drag in spite of the forward movement of the water on the crest.... (Ibid.)