Stability and righting ability

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Adopo

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USA
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Calypso
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1981 Fairchild Scout
I found this article written by Loose Canon of interest. Sometimes you look at a a boat and wonder how it does with stability. What's it like in an extreme sea state and in particular a beam sea.

So, to tie this in, we are going to Australia and New Zealand on a Ponant cruise so I started looking at boats for sale there and came across this Nordhavn. This build is interesting to me because they seemed to go well beyond what most owners do to ensure it meets and exceeds their safely concerns. How many pleasure boats are built like this, to this standard? Any Nordhavn owners or others with similar passage makers please chime in.

Here is the Loose Cannon Story on the rollover that killed the skipper/owner


https://loosecannon.substack.com/p/trawler-skipper-dies-probe-finds

By American standards the Australian coroner’s inquest into the death of a recreational trawler yacht owner is remarkable. Unlike the reports of our own National Transportation Safety or the British Marine Accident Investigation Branch, the account is highly personal as it describes the life of Allan Beeby and his death aboard the Eliza 1.

The September 2023 report reads like the outline for a movie. (Downloadable, below.)

Eliza 1 was a 2008 Halvorsen 42 Coastal Cruiser which was first commissioned by Halvorsen Boat Sales Australia and built by Poly Marine in the Southern Chinese Provence Shun De. Halvorsen was a venerable Australian boatbuilder.

The inquest documented how build quality had declined after the Halvorsen operation moved to China, but ultimately it was bad design not build issues that doomed Beeby, according to the coroner, who concluded:

The expert evidence discloses that the events that night were not as a result of poor weather or poor seamanship, but rather a result of a design fault. In short form the Eliza 1 was top heavy. In hindsight, this was reflected in the vessel moving like a “beach ball” on the waves, and in the expert opinion of Mr. Dovell it was surprising that the boat had not suffered a similar fate prior to its purchase by Alan.


The Eliza 1 was a 2008 Halvorsen Coastal Cruiser.
The coroner also recommended that every owner of a Halvorsen 42 and 44 be notified that they are at risk even in seas of just over three feet and winds under 20 knots. An expert witness found that neither vessel was “fit for coastal cruising.”

The Halvorsen name is also associated with Island Gypsy trawlers, also made in China. These models are not mentioned in the report.

Read the Coroner’s Findings

Inquest Into The Death Of Allan Beeby
954KB ∙ PDF file
Download
Inherent Defect Causes Halvorsen 42 To Broach, Then Roll Over
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Experts Weigh In

Tad Roberts of British Columbia, Canada, has designed numerous sail and power craft during and after his 14 years at Bruce King Yacht Design, including the Talaria 40 and Talaria 44 and the Hinckley Picnic Boat.

As always these reports raise as many or more questions than they answer, usually this is because the boat is no longer in operating condition and can't be meaningfully assessed as to it's actual fitness for purpose. We don't have any indication as to the actual condition of the fuel (or fresh water) tanks at the time of the capsize. Nor is there any information on whether or not there might have been un-discovered water in the bilge. Possibly the port fuel tank contained the majority of the remaining fuel at the time of capsize, or possibly running down wind had allowed water to enter the lazaret without the crew noticing (this happens a lot in the hours between midnight and dawn) or a bilge alarm not working. So there are some unknowns that may have contributed to this accident.

In his concluding remarks the coroner states, “They (Alan and Scott Beeby) had every right to assume that a vessel of this sort complied with basic international safety standards.” While that falls in line with basic consumer protection law, it's still the captain's responsibility to ensure the safety of the vessel and crew. If there's no stability information available, the captain needs to recognize that shortcoming and rectify it.

I would note, as I have many times in the past, there is no possible way that stability can be reasonably assessed visually. Despite all the owner's experience, and all the surveyors that looked at the boat, no one took seriously the need for some "complex calculations" to ascertain the boat's actual stability against an international standard.

This is why we all need to keep bringing this issue to light and giving it airtime. Because it keeps happening, people die every year because the stability issue was not taken seriously, and it's preventable. Of course the vast majority of boats do meet or exceed international standards, mainly because they are produced by responsible builders, and thus this sort of accident is relatively rare. Also pleasure boats are mostly used in fair weather, which certainly helps.

Looking at the photos of Eliza 1 I'm not surprised she does not meet ISO Category B stability requirements. In my experience getting a modern powerboat to comply with this standard takes some effort in the early design stages. Even relatively wide boats need to limit the number of people allowed on the flying bridge.

The report gives no mention of how Mr. Dovell arrived at a VCG (vertical centre of gravity) for Eliza, and that worries me as there's lots of room to introduce an error either positively or negatively. That being said, Mr. Dovell's calculations show a minimum GZ (righting arm) of barely half that required by the standard, and it would take a big change in VCG to overcome that failure. Again it's easy to ascertain real operating VCG by inclining the vessel, but it must be done before a capsize and sinking.

Again it needs to be emphasized that things went from fine cruising to life threatening in mere moments. Crews are always surprised at how quickly a capsize gets serious, there is no time to find a life jacket or survival suit. Vigilance and preparation are required.

Lou Codega is a naval architect who has designed ships and boats for the U.S. Navy and Coast Guard. He has designed several sportfish boats, including Cabo boats and trawyer yachts.

Nothing said about the boatbuilder turned inspector turned expert's credentials. At first reading, it sounds like sour grapes and a witness saying what the attorney wants him to.

New recreational boats sold here are not required to meet any stability standards. Used recreational boats are almost always sold as is, where is and it is up to the purchaser to determine its adequacy for the intended use. Not sure how certifying brokers increases safety unless he expects them to be able to assess the adequacy of a boat that they are offering.

I think, but am not sure, that new boats sold in Australia have to meet the same stability standards as new boats sold in Europe. But there's no telling what an owner might do to change the stability once the boat is in use. Some of the stuff I read in on-line newsgroups is truly frightening. But hey, everyone's an expert when it comes to boats.

Roger Long is a naval architect and sailor. He is an international expert on vessel stability.

Interesting. They seem to have covered all the bases in the investigation. I key right in on the statement that she didn’t roll much in a beam sea which is indicative of low stability. Read the sidebar I wrote on rolling motions for the book Voyaging Under Power, if you have not.

Sounds like the boat was unusually narrow compared to our general trawler fleet. I doubt the fuel cross-connect was much of a contributor. They sound pretty experienced not to have noticed the significant list that could have used up a good portion of their reserve stability. If not much list, fuel couldn’t have flowed fast enough in a normally sized cross connect to have contributed to the capsize.

I’d have to see a lot more of the stability analysis. Righting arm curves would tell a lot.

Ken Fickett built more than a thousand Mirage sailboats before going on build sportfish boats and then the Great Harbour line of trawlers.

I have reviewed the findings of the investigation of the death of Mr. Alan Beeby as a result of the capsize of the vessel “Eliza 1”. While I am not going to comment on the findings regarding the stability of the vessel, I find many of the other comments and suggestions from the coroner to be somewhat either ignorant or uninformed. Two issues stand out in my mind.

The first is that the coroner seems to believe that the United States has some kind of requirement for stability of a privately owned pleasure vessel. That is simply not true. The U.S. Coast Guard does have a requirement for Coast Guard Certified vessels that are used commercially, but there is no requirement for Pleasure vessels that are not used in a commercial situation.

From the report:

“New and used boats that are sold in Europe, regardless of where they are built in the world, must be certified as complying with one of these four categories. Such boats carry the mark “CE” which readily signifies to boat owners and potential owners that the vessel has been assessed to meet the relevant standards for the category of use. The United States has a different but similar requirement for certification.

“Mr. Parker gave evidence that most Australian manufacturers of larger recreational craft export a significant proportion of their production to the US and/or the EU and would therefore meet the strict design and safety specifications required by those markets.”

The above is simply not true and shows a lack of understanding of “requirements” for U.S. recreational vessels.

My second issue is the idea that the broker of a vessel needs to be proficiently skilled in the analysis of a vessel to preclude a vessel of faulty design being sold to an unknowing buyer. The document states:

“To consider the undertaking of a review by an appropriate industry body for the implementation of an industry wide code of practice and accreditation for boat brokers and retailers of imported boats that ensures safety, compliance with standards and full disclosure of information is a central focus of sale.”

Good luck with that!

I believe that to some degree this is what we fought a revolution over to avoid!

Here is the Nordhavn

https://www.boatsonline.com.au/boat...urvey-ocean-crossing-expedition-vessel/280413

Build and Feature Description

'Beyond Capricorn 1' was built to Australian survey standards in 2001 and has many extra features not usually included in the conventional build.
Requirements to comply with 'Survey' include many standard features on a Nordhavn, such as; Commercial Fire control and fire fighting equipment. However there are many other statutory requirements to meet 'Survey' standards that are difficult, if not impossible to achieve in an 'off the shelf' design.

An Australian Government marine surveyor was flown to the Ta Shing shipyard in Taiwan to witness and inspect all construction methods, procedures and design. One of the most important parts of the 'Survey' requirements and one of the most difficult to achieve is the 'Inclining' test and associated 'Stability' calculations. The 'Incline' test is used to calculate the 'Lightship' stability characteristics of the vessel with all loose equipment removed, all tanks sounded and fluid weights calculated. This information is used to establish the Lightship Center of Gravity and Lightship Center of Buoyancy. All equipment, stores, liquids, etc. Loaded after this calculation should be recorded in
the vessel's stability booklet as they and their location will change the ship's stability criteria. Two copies of the vessel's 'Stability Book' are kept onboard.
'Beyond Capricorn 1' has performed well in all sea states and has been safely and successfully operated by two people during our ownership.

There are several additions that have been made to the boat that set her apart from other 57's. The most significant and effective change is the relocation of the tender from the flybridge roof to a purpose-built rack over the aft deck. This has opened up a large entertainment area on the flybridge' capable of seating 8-12 people comfortably. The tender can still be moved onto the flybridge deck for routine maintenance.

Additionally, a 2' extended swim platform has been added on the stern. This facilitates access to and from the tender for personnel and stores as well as creating an area for swimming access and relaxation.

Two hard top biminis have been added to the flybridge area and another over the aft deck. The two on the flybridge are the base for 2.2 Kw of Solbian frameless solar panels The other hard top over the aft deck gives walk around access to the tender.
The vessel was last hauled for a hull inspection and bottom paint in Trinidad, April 2022.

The sale will be a "walk in", walk out" basis. All necessary items to run and maintain the vessel will remain onboard.

Galley Equipment
Miele oven (New, 2019)
Miele dishwasher
Franke 5 burner induction cooktop. (New 2019) Exhaust extractor above.
Miele washer/drier.
Vitrofrigo upright refrigerator (New 2021).
Vitrofrigo drawer refrigerator underneath upright (New 2021).
Vitrofrigo drawer freezer with Icemaker under upright (New 2021).
Vitrofrigo drawer refrigerator (New 2021).
Vitrofrigo drawer freezer under bench (New 2021).
Bar cabinet and glass cabinet above.
Whirlpool convection/microwave.
Dual large stainless steel sink with insinkerator(New 2021).
Electrolux espresso coffee machine.
Dualit toaster.
Korkmaz sandwich toaster/grill.
Russell Hobbs family rice cooker.
Brand new pressure cooker for induction stove.
3 induction stove saucepans and 2 frying pans.
Numerous storage and cooking dishes including 7 Pyrex oven dishes, pizza trays, lasagne dish etc.
Set of melamine dinnerware plus a few plates suitable for microwave.
Set of steak knives and forks and s/s cutlery for 10.
Other incidentals including glassware, utensils, salad bowls and servers.
Lazy Susan, breadboards, lettuce spinner.
'Bullet' style blender.
Kasanova electric chopper
Fakir electric beater
Weber electric bbq (on fly bridge).

Mechanical Equipment

Main Engines. 2 each Caterpillar 3126 Turbo charged and aftercooled diesel engines, rated output 420hp. Mechanically injected. 8000 hrs +/- Hrs at time of writing.

Transmissions. 2 each Twin Disc. Model No. MG5062V

Generators. 2 each 17.5 Kva Onan. Port Gen: 7330hrs. Starboard Gen: 7290hrs. At time of writing.

Sea Recovery RO Desalination System, rated output 50 gph

ABT 24v Electric Bow Thruster. Three operating stations, Flybridge, Wheelhouse and Aft Cockpit Control Station.

Fuel Transfer system. The primary pump for fuel transfer is a 12v Waldron 60 gph unit located at the engine room fuel manifold. There is a secondary 240v portable fuel transfer pump which can be plumbed for both internal fuel transfer or transfer of fuel from external bladders to the ship's system.

2 spare main propulsion propellers. Stored below forward cabin bunk. At access to bow thruster space.

New bilge pumps

Yat Marin, Marmaris, Turkey
'Seastar' Local Caterpillar Dealer.

All components from the raw water cooling side of each engine were removed, cleaned, painted and reinstalled. Main engine heat exchangers, fuel coolers, transmission oil coolers.
All associated sacrificial anodes were renewed at the same time.
All cooling water hoses on each engine were replaced.
Two new raw water pumps were installed. One of the pumps removed was rebuilt and is in the ship's spares inventory
Wakespeed external regulators were installed to both house supply alternators.
Injectors from port engine were removed, serviced and replaced. Tappet clearances were reset.
Electronics
2 x new Raymarine Axiom 16" screens.
2 x 24" touch control screens. Connected by HDMI to Axiom MFD's. Installed in Turkey 2021
2 x New Icom VHF radios (IC-M330) and Glomex aerials. Installed in Montenegro 2021.
2 x New Raymarine i70s Pilot Controller screens.
New Quantum 2 Raymarine Doppler radar.
New stainless radar stand.
Hand held Icom, IC-M25. VHR radio
A set of 2, marriage saver headsets.
Electrical Upgrades
Following a major electrical upgrade in Croatia in 2021 the vessel is now equipped with a full 24v Lithium battery system (4 ea. MGHE24x300) These provide power to the ship via the inverters.
In conjunction with the electrical upgrade above, a Victron Skylla 24v 100amp charger was installed. This charger will accept a voltage range of 220-250 and 50/60hz. This serves two purposes. One the vessel can accept 220v+ shore power from any marina worldwide. Secondly, the ship is now electrically isolated and protected from any shore power problems or earth leakage.
Solbian Solar (SX 144 L JBE) panels x 8 on flybridge bimini plus
Solbian solar panels x 6 on second bimini. (Total 14 panels)
The original logic of the power supply rotary switches on the 240v switchboard remains
unchanged. Except that the 'Off' position now supplies power from the inverters. To secure
the electrical system for maintenance each inverter must be switched off at the unit.
Battery Chargers installed on all main engine (24v) and generator (12v) start batteries, plus bow thruster (24v). The main engine start batteries and the bow thruster are charged by a 3 output Mastervolt 24v charge unit located in the Stb'd. Stabiliser space at the access stairs to the crew quarters/engine room. The generator start batteries are charged by a 12v to 12v DC charger located in the lazarette. All engine start batteries plus the bow thruster are 12v 'Optima' units which will withstand deep discharge and have a long service life.
Outdoor Equipment
3 white cane chairs and coffee table Alfresco.
6 folding deck chairs.
2 x folding teak tables.
Inflatable paddle board.
Passarelle, Carbon Fiber with non-slip top and hand rail.
Large Frigibar chest freezer on flybridge with seating on top. (4 cubic foot freezer)
Weber electric bbq in stainless steel drip tray on flybridge.
Built in seats and table to flybridge.
New stainless steel access ladder to bimini top.
There are 2 x flopper stoppers that are easily deployed to limit any rolling at anchor in rough conditions.
4 round white fenders
4 long white fenders
2 x long black fenders.
Miscellaneous other fenders.
Blinds
Clears to flybridge.
New poly carbonate spray screens to flybridge.
Clears and sun shades to stern deck.
Sun shades all around the salon and wheelhouse.
Full cover to pilot house windscreens, and individual covers for the remaining windows Zip up insect/no see-um screens for all 6 exterior doors.
New waterproof cover to Flybridge control panel.
Deck and Ground Tackle
Anchor Winch Maxwell VWC, VWCLP 4000,24v Electric, rated at 4000lbs linepull.
Snubbing Winch, Aft Cockpit. Maxwell VC2200
ABT 24v Electric Bow Thruster. Three operating stations, Flybridge, Wheelhouse and Aft Cockpit Control Station.
Both dry stacks have been cut and SS flanges installed to make the stacks removable for 19.6' bridge height clearance. Chicago bridge clearance requirement for completing 'The Great Loop'
Hard top fibreglass bimini to flybridge and another to sitting area behind flybridge control area.
Hard top fibreglass bimini added to cover stern deck under tender rack.
New Nardi Hookah compressor with regulator, hose and mouthpiece for underwater maintenance/emergencies. Can be set up to provide compressed air around boat. Hoses, connections and fittings onboard.
Fuel bladder system.
The range is 2,000 nm. (1683 Gallons in tanks) If you add on the bladders there is an extra 573 Gallons.... Total (2256 Gallons).
TENDER
Zodiac 4.2 metres (13.8 feet) 6 person, 40 HP Honda motor.
New VHF radio.
Raymarine, dragonfly -7 pro plotter, depth sounder, sonar.
Full waterproof cover.
2 x inflatable life jackets, stored in tender.
Safety and Rescue Equipment
Life raft x 2.
New 6 person soft case, Viking 'Rescyou' (valued at $3500.00)
Hard case life raft. Serviced over 12 months ago. (Requires inspection)
6 each SOLAS approved Life Jackets.
8 each inflatable life jackets, stored in Fwd cabin.
EPIRB. New 2021. Battery due for replacement November 2025. Can be reprogrammed for new MMSI, Flag State and owner details.
Spare SS 100 kg 'Nordhavn' CQR style secured on bow.
Upgrades
Gocek, Turkey. 2019 D-Marin marina.
New hardtop Bimini installed on Flybridge over original S/S tubing framework.
8 new Solbian Solar panels installed
Yat Marin Marina and Shipyard, Marmaris, Turkey. 2020.
New hardtop bimini fabricated and installed on Flybridge, aft. New 316L support structure fabricated and installed at the same time.
New SS ladder (removable) installed to access new bimini above.
New Port and Stb'd. Flag poles added to new aft bimini.
New Weber BBQ installed on new BBQ rack on flybridge.
New LED search light bar (Fwd. Flybridge), and 2 flood lights installed on Flybridge roof.
New LED flood lights installed at aft swim platform.
New hardtop bimini fabricated and installed over aft deck (gives solid walkway access to tender. )
New poly carbonate spray screens to flybridge.
Replaced aft swim platform teak decks.
Hull and Superstructure were polished and waxed.
New anti-fouling was applied, and running gear finished with 'Propspeed'.
All gel coat cracks were ground out and repaired.
Waterline and Superstructure 'trim' lines (Gold and Black), were removed and repainted.
SCT Shipyard/Marina,
RegionEurope
LocationSydney based dealer
ReferenceNord 57 chart
UsageFamily, Leisure, Cruising
Launch Year2001
DesignerNordhavn
BuilderNordhavn
Length57' 3" - 17.45m
Beam17.58 ft
Draft5.75 ft
Hull MaterialFibreglass/GRP Built to cross Oceans
Deck MaterialGRP
Engine MakeCaterpillar
EngineEngine 1 Engine Make Caterpillar Engine Model 3126 Engine Year 2001 Total Power 420hp Engine Hours 8000 Engine Type Inboard Fuel Type Diesel Propeller Type 4 Blade Propeller Material Bronze Engine 2 Engine Make Caterpillar Engine Model 3126 Engine Year 2001 Total Power 420hp Engine Hours 8000 Engine Type Inboard Fuel Type Diesel Propeller Type 4 Blade Propeller Material Bronze
Number Engines2
Fuel TypeDIESEL
Max Speed11 knots
Cruise Speed9 knots
PropulsionShaft drive
ThrustersBOW THRUSTER
Genset2
Fuel1683 gallons
 

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Great post AD

On the new boat build I note the dinghy was moved to a lower location- a presumably smart move. But the heavy solar panels and a fly bridge hard top were then added aloft. Do I sense a disconnect?

The Cat 3126 engines seem a less acceptable choice but popular in lighter craft 25 years ago. But, older N57s are a very much sought after vessel for a major refit vs buying a newer more expensive N. I continue to rue the day that accepted offer I had on a 57 was pulled from the sale as the owner’s health miraculously improved.
 
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Skimming through the epic post above I wondered if the Halvorsen 42 was built any different than popular cruising trawlers that we see here in the US. AFAIK, there have been no trawler capsizes of trawlers in the US in coastal semi-protected waters.

FWIW, I have been in 6-8’ seas on the way to Catalina Island and never felt that I was reaching the limits of stability on my Mainsip 34T. That boat does have a large beam to length ratio, 14’ on a nominal 34’ boat.

So I Googled pictures and specs and saw two things specific to the Halverson 42 that may make it less stabile:

The first is the large fiberglass arch and Bimini. I bet that adds a couple of thousand pounds to the weight aloft vs a cloth Bimini supported with SS tubing. Since many trawler builders recommend limiting the number of passengers up on the fly bridges to 6 or 8, that much weight is easily obtained with just the arch and fiberglass Bimini on the Halverson.

Secondly, that hull is relatively narrow at 12’. Most 40+’ trawlers have a beam of at least 14’

So yes, its narrow beam and weight aloft result in less stability. I wonder what its angle of vanishing stability is.

David
 
Excellent post and reenforces what I’ve said elsewhere. US buyers don’t have access to stability standards being required for new boats. EU standards only apply at time of initial launch and not after normal expected wear or any modifications. Even worse for power as Gz and AVS is commonly available in the public domain for sail.
As said if voyaging would want a stability and safety (down flooding, fire, key single point failure etc.) review by a competent NA or other skilled individual before purchase.
For my current boat
http://www.glantoa.net/nordic_tugs_stability.pdf is available. The only meaningful modifications have been a SeaKeeper and a Freedom Lift. The SeaKeeper should only have a positive effect on AVS as weight is mostly below waterplane. The freedom lift as well but neutral to modestly a negative effect due to the weight of the dinghy being above waterplane. However both have a negative effect on gyradius and raise the bow 3” at rest.
Think people need to think about their own boats. Need to think about things like the weight they place on flybridges. (We store nothing heavy up there. Lockers nearly empty). Or what the weight of dinghies and associated machinery does to stability when placed on boat decks. We have solar panels up there mounted as low as possible on the boat deck. Adds 200lbs so one less person is allowed on the flybridge at the same time. No one in a seaway. The NT is a solid “B” but looking at the windows of the salon I’d be real nervous in any kind of lateral boarding sea. Even with a solid “B” I accept its limitations c/w a true blue water boat.
 
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@ Adopo
Interesting read and perspective.
In the other thread it was determined the Captain/owner that did not make it was asleep and the son was in charge and running the boat on autopilot.
My immediate personal experience suspected in the conditions described the boat should not have been on autopilot. One bigger wave and the delay of the autopilot to recover could start the chain of events that resulted.
 
Dave beam may contribute to form stability but there are other contributors. Look at the very narrow LDL pedal to the metal extreme voyaging boats. A prime example is the Artnauticas which are self righting. Even not going to the extreme of 4:1 narrow look at the Ellings which will recover from a knockdown or even inversion. Or the Deep Water yachts. Just like bulbed fin keeled sail weight placement is the major contributor to both static and dynamic stability in a good blue water monohull. Nordies are ballasted for a reason.
The problem of dependency only on form stability is easily seen when looking at the Gz curve of such boats. Righting arm is quite high at modest to moderate heel angles but then declines. It even may become near neutral or negative as knockdown approaches. It’s usually remains negative with inversion. That’s why it’s de rigor to build escape hatches to allow egress with inversion of multihulls in blue water service. Personally think you want some form stability at modest heel angles but also righting arm from simple weight below the surface. On sail have often put the rail down but once there’s waves of significance striking the bottom paint reef or change angle of attack. Boats don’t usually slowly go over. They flip quickly when that one bad wave catches them wrong. Have never been inverted but that’s what happened in the few knockdowns of the past. The Mainships are fine boats and like most SD hulls (including my own) gain some dynamic stability once moving. However often this is mainly useful in moderate conditions. Reporting wave height without reporting period gives less than half the story. Being in three meter ocean swells allows you to cook without putting foulies on or sleep without leeclothes. It’s when there’s a short period and/or harmonic large ones from converging wave trains or breaking waves that things get interesting.
 
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Our Long-Cours 62 was not too beamy 5 m for 19.45 loa
BUT we kept à low center of gravité.
After check ( whitout the volume of the roof/wheelhouse ) we still have positive stabilité up to .. 96°.
Had the near 30m3 of roof/wheelhouse your are selfrigthing.

Some time I saw motor take an important angle of hill (?) Just left her mooring and take à short Turner at very low speed...
Remembrement à sea trial of à Nordhaven 40 on english magazines where journalist had big "douts " on stabilité...
 
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I suspect that the majority of recreational boats that transit the Panama Canal are not trawlers and not sailboats, but sport fishers. These boats are designed to go fast and handle big seas. AVS and CV be damned.

Frankly, I wouldn't be surprised if Vikings outnumbers all sail and trawler combined through the Canal.

Are we, as ex-sailors, guilty of being to narrow on how we define seaworthiness?

Peter
 
Here is a capsizing I think most of us have seen. Interesting to read the comments along with the videos...



@markdelozier8260
3 years ago

I was the USCG Accident Investigator on this capsizing incident back in 1988 and Interviewed the survivors and crew of tender and flew out to Montague Island to craw aboard the Linda’s Draw after it came ashore as a total wreck. Vessel had fuel management issues, weight management issues, too much weight aloft, skiff shifted to port and loosely secured. Excellent work from Tender crew who saved the lives of Linda’s Draw crew. Vessel was heading north following the Herring Sac Roe Fishery in Southeast Ak. to PWS. This was a big money fishery back in the day before EV Spill in 1989 and then it all collapsed. I also was Lead Investigator on EV Grounding a year later.

@fishdirect
7 years ago

Our seiner was in the same storm, heading into Prince William Sound for the Herring season. Actually saw the video in Cordova on the Alaska Eagle when they got into town. The main reason it was floundering so bad was because the seine (net) was in the fishhold without the bin boards in, causing it to shift weight over to port. Also the skiff had shifted to port creating even more stability issues..


@dave9072000
5 years ago

This happened just outside of the entrance to Prince William Sound. Boat was bound for Cordova. I'm from there and from what i know about this incident (just things I heard from my Dad and other fishermen) the owner of this boat had his son running it. The guy was scared (of course) and kept too much power on. This is not unusual. You want to just get inside shelter and out of the storm. Hard to deny adrenaline and slow down. Many times if you just pull back on the throttle in deep sea conditions you reduce risk considerably. Also, they had the jitney on deck, and it filled up with water, plus they had the boom up with the power block on it. This all caused too much weight too high on the vessel, reducing stability. This is just what I've heard. The video seems to confirm this, but I wasn't there so I may be wrong.


@galehann2205
1 year ago

If you watch the video Linda's Draw was crossways on top of a massive roller that was breaking from both directions. The wave just picked the boat up and laid it on it's side. You may ask how I know this. I was a crew member on the Alaska Eagle at the wheel when we found them. Not only did I take the video, I threw the lines that got all three crew members onboard the Eagle. My name is Gale Hann and I worked for Ted Morehouse for four years.

 
#11 is an excellent post. Thanks

Think SF have a lot of dynamic stability. On occasion crewed a Enrique that went out for pelagic fish and amazed how well she did meeting headseas. Same with well powered deep V large center consoles. Both types somewhat uncomfortable if not moving or at trolling speeds in a beam sea. So think you’re right Peter. Too many conversations focus only on static stability. However when things go really south ( stick goes down or power is lost) it’s static stability that’s the only game in town. Think that’s the genius of the Jordan series drogue. You’re not taking seas over the bow like with a sea anchor but aligned to cushion the blow while progressing forward. But aligned in the long axis and the drag prevents pitchpoling. Maximum static stability for that hull regardless of conformation. However for most SD recreational trawlers not a reasonable option due to construction features.
 
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I suspect that the majority of recreational boats that transit the Panama Canal are not trawlers and not sailboats, but sport fishers. These boats are designed to go fast and handle big seas. AVS and CV be damned.

Frankly, I wouldn't be surprised if Vikings outnumbers all sail and trawler combined through the Canal.

Are we, as ex-sailors, guilty of being to narrow on how we define seaworthiness?

Peter

Yes, I do think that is the case. I’m a powerboat guy from the start but I’ll take the hit along with the sailors.

Vikings are brick outhouses. The design logic is greatly different from that of a sailboat but they survive and routinely travel long distances in all conditions. There is more than one way to achieve and measure seaworthiness. Vikings aren’t the only capable sportfisher but are very big sellers for good reasons.
 
Yes, I do think that is the case. I’m a powerboat guy from the start but I’ll take the hit along with the sailors.

Vikings are brick outhouses. The design logic is greatly different from that of a sailboat but they survive and routinely travel long distances in all conditions. There is more than one way to achieve and measure seaworthiness. Vikings aren’t the only capable sportfisher but are very big sellers for good reasons.

Guy
+1
To your sport fisher boat comments, Michael Rybovich has an on-point article in the January 2024 P&MY magazine that is a good read.
 
My first thought is, ‘what am I doing out here?’ Second thought, ‘how do I safely retreat?’
So much for a ‘good weather window’.
 
Interesting read on the capsize, there are so many variables in boats, how they are used,loaded,ran that I think it can be a stretch to specifically blame one factor as the cause.


Regarding the N57, twin 400 hp motors is a great way to screw up a great single engine boat that is smooth and very fuel efficient.
Hollywood
 
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Most boats can be kept upright in tough seas if you still have power, or if you have a sea anchor and knowledge and distance from shore. If you lose power, maybe because the seas have stirred up your fuel tank and clogged your filters, though, there's no substitute for ballast. 1/4 of my powerboat's weight is ballast in the keel. It's comforting to know it's there keeping the right side up.
 
Excellent post and reenforces what I’ve said elsewhere. US buyers don’t have access to stability standards being required for new boats.

Think people need to think about their own boats. Need to think about things like the weight they place on flybridges. (We store nothing heavy up there. Lockers nearly empty).

This hits the nail on the head for many coastal cruisers. Most people only consider capsize/rollover in extreme conditions.

But without knowing the curves, consider how many have 3-500lbs of dinghy and other stuff up high and what that does to your righting moment of effort. (500 lbs 10' up off the waterline that when it becomes horizontal is now probably 10-30% of the weight of many boats that people on this forum own).

This makes little difference with 2-3' waves in 15kts. But say you get caught out in T storm/squall where it is now 25-35 with 4-6' and on the beam.

I don't think people realize that once you hit your AVS magic number, where it might have been linear along the curve, it is now binary regarding if you are going over. You are.
 
Here is a capsizing I think most of us have seen. Interesting to read the comments along with the videos...



@markdelozier8260
3 years ago

I was the USCG Accident Investigator on this capsizing incident back in 1988 and Interviewed the survivors and crew of tender and flew out to Montague Island to craw aboard the Linda’s Draw after it came ashore as a total wreck. Vessel had fuel management issues, weight management issues, too much weight aloft, skiff shifted to port and loosely secured. Excellent work from Tender crew who saved the lives of Linda’s Draw crew. Vessel was heading north following the Herring Sac Roe Fishery in Southeast Ak. to PWS. This was a big money fishery back in the day before EV Spill in 1989 and then it all collapsed. I also was Lead Investigator on EV Grounding a year later.

@fishdirect
7 years ago

Our seiner was in the same storm, heading into Prince William Sound for the Herring season. Actually saw the video in Cordova on the Alaska Eagle when they got into town. The main reason it was floundering so bad was because the seine (net) was in the fishhold without the bin boards in, causing it to shift weight over to port. Also the skiff had shifted to port creating even more stability issues..


@dave9072000
5 years ago

This happened just outside of the entrance to Prince William Sound. Boat was bound for Cordova. I'm from there and from what i know about this incident (just things I heard from my Dad and other fishermen) the owner of this boat had his son running it. The guy was scared (of course) and kept too much power on. This is not unusual. You want to just get inside shelter and out of the storm. Hard to deny adrenaline and slow down. Many times if you just pull back on the throttle in deep sea conditions you reduce risk considerably. Also, they had the jitney on deck, and it filled up with water, plus they had the boom up with the power block on it. This all caused too much weight too high on the vessel, reducing stability. This is just what I've heard. The video seems to confirm this, but I wasn't there so I may be wrong.


@galehann2205
1 year ago

If you watch the video Linda's Draw was crossways on top of a massive roller that was breaking from both directions. The wave just picked the boat up and laid it on it's side. You may ask how I know this. I was a crew member on the Alaska Eagle at the wheel when we found them. Not only did I take the video, I threw the lines that got all three crew members onboard the Eagle. My name is Gale Hann and I worked for Ted Morehouse for four years.


Very interesting, I have always had questions about the Linda's Draw incident. Would you happen to remember what she had for a Main? HP rating? Any reported engine problems during this incident?

Skiff on deck, Main Boom & Seine Block aloft in that sea state is definitely asking for problems. Don't know what that crew was thinking.

However, after watching this video numerous times over the past years, I cannot help but say they were definitely having engine problems or were forced to run at grossly reduced power due to a clogged fuel filter etc. If you look at the turbulence of the water at the stern, it honestly looks like they are steaming at no-wake speeds under 1200rpms which would not give you much control running down sea in those conditions, very strange to me.

I run a similar setup, 42ft Rawson Seiner with a single 6BTA(260). At 75% Power, 2500rpm/9knots, lots of turbulence in the water at the stern, Hot & Loud Exhaust w/some smoke, Bow Elevated etc. You can definitely tell when these boats are steaming ahead although they are not going fast.

-Otis
 
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A thank you for the video and your work to record it. Your observations and interpretation seem quite astute. Been struck over time running without drogues is more dangerous than beating on sail or bare poles. Do not have experience of really heavy weather in power. I think for both most dangerous is when a boat that’s already heeled significantly is struck by another wave on its exposed bottom. Like you I replayed the key seconds of your recording and think that’s what happened here.

RL has been kind enough to share his considerable expertise concerning stability and wonder if he would share his thoughts on the immediate cause of the recorded event.

I wonder if the is the AVS is only factor in survivability in heavy weather. It’s not unusual to have several wave trains. Nor is it unusual to have varying periods and heights. Wonder if multiple factors beyond just the AVS are important. Particularly how quickly the boat recovers from a heel as well as its ability to slide on a wave front. Of course downflood risk and quickness of clearing green water are other factors. Further wonder about heavy v light, shoal v deep, narrow v beamy if all with similar AVS. Similarly throughout this thread and the others here there’s been little discussion about pitch and reserve buoyancy at the ends. Perhaps as with the Pride of Baltimore this can be quite important. Particularly when running and surfing. Ultimately we don’t care about the numbers except as input to tell us if the boat is safe. Fatigue is a major issue in weather. I’m not educated enough to understand why some boats are much harder to work than others in similar circumstances. If you assume they had engine troubles why weren’t they addressed? Too hard to do in a seaway? Not set up to merely hit a level to switch filters? Dangerous to go into the ER?
 
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