Multihull Capsize Prevention <split>

Here's the thread http://www.boatdesign.net/forums/mu...n-methods-fwd-crossbeam-42500.html#post543432 your referencing Catbuilder, I believe that your misinterpreting what has been represented by Ad Hoc within it. Regards from Jeff.

 

Waikikin.

Indeed. Thank you for pointing out the gross misrepresentation, simply to look good in the eyes of the acolytes....seems some what sad to me.

This is sadly, the problem when someone is presented with facts or evidence to the contrary or anything really that goes against their belief system. They immediately see red, and rely on pure personal and ad hominem retorts. Subverting anecdotal evidence as fact is their rationale, assuming all will swallow it, as their fellow partners in crime and acolytes do. Don't question me, just trust me, believe me...i know better attitude....why..because you say so??!!

Luckily for the rest of the world, it engages in sound science and engineering rigour that is constantly being critiqued by many to ensure that no stone is left unturned in the pursuit and quest for knowledge and furthering our knowledge and understanding in all things around us.

Misquoting is a classic example of: why let facts get in the way of a good story!

Those that rely on anecdotes are the same type you meet in a pub propping up the bar.

 

20 knots. I rest my case. Thank's for being honest.

 

Again vitriol and personal attacks. It would have been so nice to talk about Multihulls rather than constantly using diatribe. All you are doing is avoiding any discussion. The reasoning you have presented so far is "you are wrong because I'm right". The rest of your posts are like you posted here; hot air.

And who's claiming that their education makes them superior ? No one else has mentioned their education. Just tried to provide facts and explanations.

If you really have a masters in Physics I'd like to talk to the physicist please. Can you comment on the storm jib scenario.

 

It is most peculiar that the only person feeling intimidated (well...) by others posting evidence for debate, or wishing to engage in a rational logical discussion, is crying fowl of others as being superior, yet, feels the need to post their qualifications as some kind of vindication????

No one here, as far as I can read has said their qualifications are XXX, so trust me believe me, I am right you're wrong. Other than whom has posted theirs!

As you say, just post facts and explanations....nowt else is required. Certainly not polemic clap trap.

 

Maybe everyone could get back to Collision survivability and leave the waves for another thread......Almost every mutihull book covers the subject well.
Foam bows have been suggested but there is one challenge when also trying to incorporate a capsize righting system. It would then have to be a over the sterns method rather than bows. This works but means sending engines etc...under water. Lateral righting takes more energy....The bow on rails idea could lend itself to removal for rerighting purposes. Other ideas?

 

Definitely my last comment on the Goons - the wind speed was NOT the point, MJ, it was the large swell that was running after the hard blow (this thread subject included waves, no?) ... and the funneling affect near the falls by Channel Island ... and the tide against same ... and we were there.

 

How does 20 knots true with a full main and a large jib on a big well crewed racing cat relate to carrying just a storm jib in a gale ? You impressed SR with name dropping but I don't see how this relates to a survival situation.

And how would you have felt taking all the sails down and sitting like ducks as CB has been claiming is an invulnerable tactic. I note you haven' actually supported him with that premise.

 

To MJ.
In my eyes its an welcome adition to multihull handling, in hairy possibly capsize situations, Gary talks about. It describes the special, not out of the book, forces working on the cat in that particular moment in a special place.
It is similar and related to your welcome remarks and I quote:
"There is a dynamic effect with anything you push off the centre of mass, jab anything on your desk off the centre line and watch what happens. It rotates.

With the boat heeled already on the wave front the plunging breaker is pushing the centre hull and you could draw the inversion process superimposing the craft on the wave front. Effectively it’s like a cat with much less beam and with a lower volume in the leeward hull. Where the breaker pushes relative to the centre of mass is a dynamic couple, add to this the moment from resistance from a the more deeply immersed lee hull. There is also a lower roll inertia than there is on a Catamaran, this relates to impact energy and angle of heel."

I've been a professional sailor, yes on sailboats but not multihulls, for the better part of my life but know for a fact that if you are at sea, especially in hairy situations, you have to use all your sense and senses; literally and figuratively. Both brain halves working together if you will.

Curious about multihulls,

Cheers,

Hielan

 

Thanks Hielan,
finally some common sense coming out now. It would be interesting to hear from Richard woods and Old sailor on the subject, as I would think they would have some use full Advice/comments on wave induced capsizes.

 

Written by Douglas Campbell. About the loss of a Lagoon 38 in the Atlantic in very nasty weather.

The forecasts the crew was receiving over a single sideband receiver, satellite phone and weatherfax suggested that conditions ahead were worsening. But the captain seemed convinced that the boat could handle the 35 to 45 knots of wind forecasted. "I took it on trust that the captain was confident about the weather," says Templeman. The boat was southeast of Bermuda. Hobley decided to sail north of the island, knowing that the predicted winds would blow first from the southwest and then the northwest.

Klinges went off watch Sunday night, Feb. 18, with the boat sailing through 30-foot swells. "When I woke up [Monday] morning, the waves had exponentially grown, and they were pretty steep because they were pushed by the wind," he says. "Not rollers anymore, [but] long back and steep front. At 10 that morning the waves were getting noticeably steeper, and I was getting apprehensive myself because I could see all around us the waves were breaking everywhere."

"As we progressed, the front approached, the weather deteriorated, and [the wind] went to 55 knots, gusting to 60, and [up to] 45-foot waves," Templeman recalls. "The problem was that one in 10 waves would crest. By this time we'd seen the weather had deteriorated far more than forecast, so we were heading southeasterly with a 30 percent jib and no mainsail. We had no other option but to run."

Hobley took over the helm in the cockpit - the only steering station on the catamaran and the place where the life raft was stored - at 11 a.m., running in front of the sea and keeping the waves just off the starboard quarter. At times, he took a break and let the windvane or the autopilot do the steering, his crew says. At one point Templeman noted they were doing 22 knots as they raced down a wave, although on a regular basis the boat was making 10 to 12 knots. Everywhere around them were 35-foot seas, along with the occasional breaking 45-footer.

As Monday wore on, "the water was screaming, and the wind was screaming," says Klinges. "It reminded me of being in the mountains when the wind blows the snow in streaks."

Templeman and Klinges were in the saloon at around 2 p.m. with Hobley, who had turned on the autopilot and taken a break from steering. Klinges was on a couch on the port side and Templeman was standing to starboard when, through the sliding glass doors that separated them from the cockpit, they saw another 45-footer approach.

"I could see a huge one crest and break on a direct line for us," Klinges says. "Pretty soon it came up, a 45-foot wall, straight up and down white with foam. It broke on our starboard quarter, blew the hatch cover open, filled up the cockpit, flooded the saloon floor. I was sitting on the saloon couch, so basically I rolled with it."

Earlier in the afternoon, when a similar wave slammed the catamaran from astern, Templeman had been thrown across the saloon and down into the port hull. This time he was putting something away in his stateroom and felt the boat tilt 90 degrees and then slam back down.

"We were probably 5 degrees from flipping over," says Klinges. "After that, I kind of came to the conclusion that if that one wave was there and the wind wasn't letting up . our luck was probably running out." He put on all his ski gear, an extra layer of fleece, his inflatable life jacket and his three-point tether and went to his stateroom forward in the port hull to lie in his bunk.

At 4 o'clock in the afternoon, with squalls of heavy rain that changed the wind angle, Hobley went below, shedding most of his gear except for his thermals and a layer of fleece. With Templeman in the cockpit steering, Hobley got into his bunk, on the opposite side of the boat from Klinges' stateroom. An hour later, at 5 o'clock, Templeman saw the one-in-10 wave, another 45-footer, approach from astern, cresting twice. "The third time, it crested just as we came to the top of it and flipped the catamaran over," he recalls.

Templeman found himself trapped in the inverted cockpit, unable to open the sliding glass doors to the saloon. Klinges, in his port-hull cabin in full foul weather gear, simply walked out of his bunk and onto the overhead as his cocoon turned upside down. As he made his way aft, he encountered Hobley, still only in thermals and fleece. The skipper had taken just enough time to put on his life jacket. The pair went aft to the escape hatch on the hull. Klinges had grabbed the ditch bag, in which the EPIRB was stored, and had it fastened to his harness.

Outside, 35-foot waves attacked the boat relentlessly, funneling between the hulls like racing surf. Klinges popped the escape hatch, reached outside and clipped his tether to a D-ring, then climbed out of the hull, with Hobley right behind. Caught in the water racing between the hulls, Klinges was yanked fore and aft several times, then finally made his way to the bow. He was shaken. The hook on his tether had been bent. He had never been in seas like these.

"Tell me we are going to get out of here!" Klinges shouted to Hobley.

"Absolutely," the skipper shouted into the crewman's face. "We are going to get out of here!"

Now Hobley and Klinges were joined at the bow by Templeman, who had managed to open the sliding doors and get out the escape hatch in the starboard hull. The life raft that had been in the cockpit was nowhere to be seen. Hobley busied himself activating his EPIRB, which was registered to another boat, named Haley. The long EPIRB tether got tangled around him and Klinges, then the tether snapped and the beacon was washed overboard. Meanwhile, Templeman had activated his personal EPIRB. So two signals were being broadcast to search-and-rescue authorities.

About a half-hour after the capsize, Klinges realized that Hobley had no tether, and he hooked the skipper to is own line. "Rather quickly, it became apparent that the skipper wasn't very well-protected," Templeman says. "He started shivering. We were actually sitting [on the catamaran's trampoline] in the water, losing a lot of heat to the water. I suggested that we stand so the water could drain. Me and Kevin stood up" in the lee of one of the catamaran's hulls. "The skipper questioned why we were standing up. He was becoming less and less responsive. We were doing everything to keep him awake . shouting louder and louder to keep him fighting. But it was quite a strain. We were also trying to keep ourselves on the deck."

Then the ditch bag was torn away from Klinges. "The waves were just destroying us, throwing us overboard," he says.

An hour into the ordeal, with dark descending on the Atlantic, the trio saw a light shining on Templeman's EPIRB indicating that its signal had been received on shore. Some time later, Hobley began tearing at his life jacket as if trying to remove it, and he became incoherent. It was around 10 p.m. when a C-130 aircraft arrived on scene. Then a train of huge waves arrived, as well. Templeman was standing next to the hull, and Hobley was between him and Klinges. One of the waves shoved Templeman into Hobley, who in turn slammed into Klinges, knocking him into a cable and rupturing his inflated life jacket.

Between waves, the men saw flares and strobes dropped by the aircraft, and at one point they saw an inflated life raft float by but did not dare swim for it. A subsequent wave washed all three overboard, and when Klinges, pulling on his tether, hauled Hobley back to the boat, he could see the skipper was dead. "His eyes were still opened, and I closed his eyes, and I couldn't believe that," he says. "And the next wave blew us all over, and I pulled in the line, and the only thing there was the life jacket."

About two hours later, another C-130 from Coast Guard Station Elizabeth City (N.C.) landed in Bermuda with Lt. Cdr. Adam Kerr, a helicopter pilot, on board. Kerr and his crew took over an HH-60 Jayhawk helicopter that had been flown to the island by another crew, and they headed for the catamaran, 90 minutes to the northeast.

Flying with night-vision goggles, Kerr and his co-pilot, flight mechanic and rescue swimmer could barely see anything. When they arrived at the cat, Kerr set the radar altimeter, which keeps the chopper in a hover at a chosen altitude.

"It was complete whitecaps, and our altimeter would go from 60 feet to 30 feet to 20 feet," Kerr says. Turning on his search lights, the pilot saw two men huddled at one side of the catamaran. "And the waves were breaking over the top of them, just repeatedly crashing."

What unfolded now was the most demanding rescue in Kerr's seven years of flying. "Those waves were huge," he says. "You would see the sea spray blowing off the back side of it, blowing right past my window."

Now it was the rescue swimmer's turn. Michael Ackerman changed into his swim gear, clipped the cable onto his harness, and descended through the spume toward the waves. Moments later, he surfaced in front of the catamaran.

"Hey, my name's Mike," he said to the astonished sailors. "I'm with the Coast Guard. Are you guys injured?"

It had been 10 hours since the catamaran capsized.

 

Here's another writeup of a cat flipped by waves by Douglas Campbell

This was Queequeg 2 a Hugo Myers 43 foot design.......

Off watch for 15 minutes, Sherman was bending over a food box forward in the main cabin of the catamaran. When the big wave hit, he says he “basically completed a summersault.” First, he fell onto some storage boxes and then a padded bench, he says. “After that, it would have been onto the [overhead]. I got a fat lip and a few gouges on my left elbow from some bolt heads in the [overhead], which were the bottom side of rigging mounts.
“The contents of the cabin bounced and banged around loudly, scattering all over the room as the vessel flipped end for end,” Sherman says. The yacht “spun immediately” so that the companionway opening to the inverted cockpit once again was facing the onslaught of the sea. Water poured in, and “everything mixed and moved, making it extremely difficult to identify and/or locate anything,” he says.
The boat was some 180 nautical miles south of Madagascar when the M/V Auto Banner found it Jan. 22.
The yacht’s diesel tanks had come loose and spilled their contents inside Queequeg II, Sherman says. “Diesel fuel was everywhere. Joe and I were covered in it. I called out to [Strykowski] to see if he was OK,” Sherman says. “He said: ‘Yes.’ ” Sherman says he then told Strykowski to secure two 5-gallon jugs of drinking water, which he quickly did.
“I immediately went for my [dive] mask,” Sherman says. Then he and Strykowski began gathering equipment and supplies in water that ranged from chest deep to neck deep. “We had to eject large pieces of cabinets to see the items at our feet,” Sherman says, and “these [cabinet] boards were banging into us. We located the EPIRB, water, a flashlight, cooler with some miscellaneous food items, dive suits, life vests,” and, a little later, a tool bag.
The men dressed in their dive suits to protect against hypothermia. “We were reaching and sorting anything and everything that we could see, get to and secure,” Sherman says. “I hunted a long time for the sat phone and GPS. I gave up on those because I knew they would be ruined.
“Things were escaping/floating out the back [of the main cabin] rapidly with the cabin filling with water,” he continues. At the point when the water level in the main cabin reached their chins, the men decided to move to the closest hull, on the starboard side of Queequeg II. But once they reached the starboard side, they concluded that they should be on the port side, where most of their gear was stowed.
“Joe had found two short pieces of rope [tied together],” Sherman says. “I was to swim across and secure my end of the rope and pull twice” to indicate arrival in the port hull, he says. Sherman says was going first because he had his mask and fins and Strykowski had none.
The plan was that when Strykowski felt the two tugs on the rope, he was to return the signal and then use the rope to pull and swim across the saloon to the port hull, Sherman says. Sherman felt two tugs and then he waited, he says. But Strykowski never arrived and Sherman was unable to find him on a return trip to the starboard hull.
The interior of the catamaran became dark not long after the capsizing, Sherman says. He spent the night in darkness and noise, waiting for light to make some moves.
“I always had faith and a belief that I would make it,” Sherman says. “I had some water, food and some equipment. I was totally committed to doing everything possible to stay alive, even if it meant weeks or months.”
The next day, Wednesday, Sherman was busy. “I had a number of survival objectives keeping me active,” he says. He also had reflected light, shining up from the sea beneath Queequeg II, filtering into the boat through its main cabin door, the portholes and hatches. Working with a hammer and wood chisel, Sherman managed to chop a hole large enough to pull himself through in the port hull by late Wednesday afternoon.
Squirming outside, he tied the EPIRB to a propeller housing and then returned to the inside of the boat. “I could have swam out at any time, but I was protected and sheltered from the severe weather, inside the hull,” he says. “This was where my food, water and supplies were stored.”
Sherman spent another dark night inside Queequeg II. But at about
9 o’clock on the morning of Thursday, Jan. 22, he looked outside and saw a ship. It was the Auto Banner, a vessel enrolled in the volunteer AMVER program in which ship owners commit to help in rescues at sea. Sherman says it took him about an hour to prepare to leave Queequeg II. When he did, he says, he swam to the Auto Banner, where crewmen lifted him aboard, entangled in a rope ladder.
The Auto Banner had been routed to Queequeg II by U.S. Coast Guard watchstanders in Miami, who had received the EPIRB signal from the Florida-registered boat. Petty Officer James Harless, of the Seventh Coast Guard District, says his unit alerted the Marine Rescue Coordination Center on La Reunion Island in the Indian Ocean and then helped design a search plan for Queequeg II and recruited the Auto Banner.
Harless says aircraft from the U.S. and South African navies were dispatched to the scene, along with a frigate from the French navy. He says divers from the frigate searched the yacht but were unable to find Cultra or Strykowski.

 

Here’s the account of Gulliver the Kysna 440 blown over off SA last year:

The wife of the skipper Greg West, reported … All efforts to raise the yacht had failed.

Maritime Radio Services had been trying to get into contact with the yacht by VHF Radio and the NSRI Knysna volunteer alerted NSRI Mossel Bay.
In the mean time NSRI Still Bay, NSRI Witsand and NSRI Agulhas were all placed on high alert.
It was then confirmed that an EPIRB (an Emergency Distress Radio Beacon) was intercepted by an international monitoring Maritime Search and Rescue agency and they had alerted South African Maritime Search and Rescue informing that the emergency distress beacon belonging to the Knysna yacht Gulliver was emitting the Emergency Distress Signal some 12 nautical miles off-shore of Cape Infanta.
It was suspected at this stage that the yacht had either capsized or sustained severe damage and the fate of the 4 crewmen was not known.
On learning of the EPIRB activation it was decided that NSRI Witsand (the closest sea rescue station) would launch our 5.5 meter Rigid Inflatable rescue craft Queenie Paine to respond to the position of the EPIRB while NSRI Still Bay would send a relief crew to our rescue base in Witsand as back-up.
Metro EMS and the SA Police Service were activated to respond to our rescue base in Witsand to stand-by.
NSRI Witsand launched our sea rescue craft Queenie Paine at 19h28 with three rescue crew on board and we negotiated up to 5m rough sea swells and a gusting up to 60 knot wind in very dark conditions.
We then set off an illuminating flare and noticed a small flickering light just over one nautical mile away from us and we motored towards the light.
On reaching the flickering light (at around 23h00) we found the upturned (capsized) hull of the yacht (a 40 foot catamaran) and all 4 crewmen were found in a life-raft which they had tied to the capsized hull of their yacht.
The men told us that their yacht had been capsized by a sudden extremely strong wind squall at around 13h30 while they were motor sailing and they had manually set off their EPIRB which had required Shaun Kennedy to swim under the yacht to release the EPIRB.
They had also all been huddled on the upturned hull of the yacht before releasing the life-raft later in the day – which also required swimming under the yacht.
They explained that the life-raft had suddenly been caught in the strong winds and it began to be blown away from the upturned hull of the yacht but one of the men managed to swim after the life-raft catching up with it and swimming it back to the capsized yacht.
The 4 men were suffering hypothermia and shock (only one of the men was seriously hypothermic) and we took them onto our sea rescue craft and began the difficult task of motoring back towards shore.
NSRI Agulhas were called to assist and they launched their 8.5 meter rigid inflatable sea rescue craft Vodacom Rescuer VII and two fishing trawlers that were in the area were requested to be on the lookout for our sea rescue craft which we at this stage were limping back towards shore in huge sea conditions with a very overweight sea rescue craft but managing to just make headway.
But at around 01h00 we limped into Witsand aboard Queenie Paine and all 4 men have been transported to hospital by Metro EMS ambulance for treatment for hypothermia. All 4 men are in stable conditions and we suspect they will be released from hospital shortly.
A Maritime Navigational warning of the upturned hull of the yacht floating and adrift some 12 nautical miles off-shore of Cape Infanta is broadcast and the fate of the capsized yacht is not known. The NSRI suspect the owners will attempt salvage efforts.
SAMSA (The South African Maritime Safety Authority) will investigate the incident as per standard procedure.
Greg West’s wife is commended for raising the alarm.
Update: Crew released from hospital:
The crew of Gulliver, skipper Greg West, 60, his crew Frans Sprung, 76, Shaun Kennedy, 34, from St Francis Bay and Mike Morek, from Knysna, have been released from hospital and are to return home.
They had been sailing from Langebaan to Knysna and were attempting to outrun the weather, trying to reach Mossel Bay, when a wind squall capsized their yacht at approximately 13h30 off Cape Infanta.
An emergency EPIRB (Emergency Distress Radio Beacon) was activated by them at around 15h00 but the EPIRB did not transmit the name of the yacht and it was only later in the day, on the insistence of the skippers wife, who convinced authorities that the yacht was missing off Cape Infanta that it was determined the EPIRB was coming from the yacht Gulliver.
A full-scale search and rescue operation was launched.
The crew of Gulliver also set off red distress flares during the afternoon but none of the red distress flares were seen.
The capsized yacht is believed to be adrift on the ocean and Maritime Navigational warnings remain in place.

 

The Atlantic 57 Catamaran Anna blown over by a very sudden 60+ knot squall after leaving Tonga in the Pacific in 2010

The designer Chris White has his comments here and they are worth reading.

http://www.chriswhitedesigns.com/news/anna_capsize/lessons_learned.shtml

 

Are you serious? The are among the best contributors in this forum and no rant won't change that fact. You made a claim and it's proven fail.. live with it.

Wind can be, and most often is, contributing factor capsizing any boat (not just multis) but big breaking waves are the real danger.
BR Teddy

ps. and thanks to Mike of those real stories!