Did a google search on this. Found some interesting articles with stories from the news, Golden Ray, Cougar Ace etc. but not much on actual stability numbers or statistic on how car ship compare with other types of ships.
That’s eight car carrier accidents in the last 20 years, or one every two and a half years. Should we be concerned? Is that a lot? Lloyd’s of London listed an average of 50 major shipping accidents a year over the three-year period 2018-2020, or 150 total for the three-year-period.
With one car carrier incident for every 150 other commercial ship problems, no, car carriers do not appear to be inherently unsafe, despite their high profiles. But they do garner a lot of attention, especially when they lie on their sides like bloated belugas in full view of vacationing tourists, as was the case of the Golden Ray.
Problem here is percentage of car carriers in the merchant fleet is not given.
Dec 4, 2020 — Today, there are 768 car carriers in the fleet, and 569 of them have capacity of 4,000 cars or more (74% of the fleet) with another 62 on order.
Thanks but I don’t intend to search for any numbers myself, my point was the articles without statistics or actual stability numbers are less than worthless.
This article has a quote from a so-called "Maritime Commentator
“In fact, these vessels – both freighters of vehicles and live farm animals – are built to the edge of safety due to commercial considerations. Their design has exceeded all reason, and these ships require very careful handling”
But further down the article there’s also a quote from a naval architect: Christian Damsgaard.
“As long as you comply with the requirements to operate safely, these ship are not more prone to capsizing than others. It is clear that it is an extreme design, but they fulfill the same stability criteria as all other cargo ships” he said.
Damsgaard goes on to say car carrier loads are very light so are built higher for capacity. Not mentioned is building up is limited by increased loading / discharge times and air draft limits on some major car ports.
Here’s an article from a P&I club.
A ship capsize is a seafarer’s worst nightmare. These incidents are often due to inadequate ship stability caused by a sudden and unplanned rise in the ship’s Centre of Gravity (CoG). Tragic consequences include injury, death, pollution and total loss of ship and cargo. All ships are exposed to this potential danger but some ship types and trades are much more exposed than others. In particular, containerships and general cargo and multi-purpose ships carrying containers on deck – with a high ship CoG and low residual stability are in the instability high risk category.
Many thx for this material. Will revert soon.
Briefly on the issue:
The seagoing RORO, car/train ferry, PCC, PTCC, ropax, with large external doors close to the waterline and open vehicle decks with few internal bulkheads has a reputation for being a high-risk design, to the point where the acronym is sometimes derisively expanded to
“roll on/roll over”.
Btw 1983-1985 we(junior officers) called our ro-ro “3 minute ship” basis damage stability books and blueprints .
Despite these inherent risks, the very high freeboard of PCC/PTCC raises the seaworthiness of these vessels.
For example, the car carrier MV Cougar Ace listed 60 degrees to its port side in 2006, but did not sink, since its high enclosed sides prevented water from entering. (improper ballast ops, as one shall not do sequential ballast ops in severe weather/sea conditions but "flow through " method as advised by regs and industry advise not to mention SMS.
In late January 2016 MV Modern Express was listing off France after cargo shifted on the ship. Salvage crews secured the vessel and it was hauled into the port of Bilbao, Spain. Cargo was allegedly an illegal shipment of precious wood/logs that got loose while at sea.
Ships as all toys or equipment MUST be used in accordance with manufacturers instruction, otherwise sh…t happens. I know two such instructions :
ship stability booklet
container and/or cargo securing manual.
To those who think the loadicator is their ultimate Guru and are happy with “all green” figures I always say : be careful as “IT” experts thought me that GARBAGE IN = GARBAGE OUT.
Loading any ship is an art but commercial pressures reduced this noble activity to simple "dumping " of the cargo and thus a term ETTO was born ( efficiency thoroughness trade off) which combined with allegedly inherent vices is a good mix for disaster to happen from time to time .
Cheers
The quality of the load plans varies from port to port. Loading new cars the ship will get the stow plan several days in advance and every single vehicle will be stowed according to plan.
On the other end of the spectrum in some used car ports the ship will only get an inaccurate plan after sailing.
I should add that typically in the case of no or poor stow plan an estimate can be used for cargo weight. Generally it’s not an issue as the ship typically has more than enough safety margin to compensate for errors in estimated cargo weights. Cars are not very heavy. Full loads or so-called high and heavy cargo could be another story.
Strictly speaking the freeboard, measured from the freeboard deck, of a PCTC/PCC is going to be roughly the same as a container ship of the same size. The ones I worked this was about 7 or 8 meters above the waterline.
On the ships I am familiar with the stern or quarter ramp is located on the freeboard deck and the number of traverse bullheads below the freeboard deck is going to be the same as a container ships of similar size because both types of ships are required to meet the same damage stability requirements.
Sorry to be late but i was busy with irrelevant things and U seemed to be busy with censoring and cancelling some " idiots"
Excellent topic worth discussing but can not find statistics. I think I have Coguar Ace blue prints but for a time being can not find it in my files , that have got messy lately.
In the meantime pls find attached file below for your kind perusal which i hope you will find interesting.
One more thing. Pls do not use smart watch to scroll my msgs as for some it is a cause of great frustration and agony
Unfortunately |I was not trained in twitter 144 character use only -sorry .
Cheers.
p.s. have just found the file size is too big then have created on my google drive folder with relevant contents . Link to the folder below and be not afraid -i am not a Russian cyberhacker/trooper
rem: anybody on this forum can use the link
Thanks for those files. It’s deck and engine operating manual for a 180 meter pctc.
Contrary to the view that car ships are basically “floating parking garages” there are many systems to deal with including a lot of cargo gear (mostly inside the ship). It’s the crew that operates the cargo gear , not the longshoreman.
Given the work load during high tempo operations car ships can sometimes have unacceptable levels of risk for crew errors, including critical errors with stability.
This is from the deck operating manual of the 180 meter PCTC.
Condition No.5 - Standard Car Load Condition (4,303 Units) Departure
In my experience a typically GoM (GM corrected for free surface) on arrival was about 1.2 - 1.4 meters. Below that the ship starts to feel too tender but still well within the required minimums.
Certainly a portion of these incidents can be attributed to bad load plans, yet we still see bad thing happen even with good load plans.
Good load plans rely on properly lashing cargo and we still hear of incidents where cargo has shifted. Certainly crews are lashing cargo down, but are they lashing it down too tightly? If too tight, the chain is brought ever closer to it’s yield point, and in a rolling sea tension situation with a 2500kg vehicle, lateral forces can really start to multiply within the lashings if prestressed too much. It’s one case where a little slack can go a long way to preventing a chain break.
Stowage plans particularly with big box ships being made shore-side and the requirement to exchange ballast water after an ocean voyage. non of which happened 30 or so years ago…
In some ports with three longshore gangs cars get loaded and lashed down at a rate of up to 400 car/hour. A load of 4000 cars would be over 16,000 (nylon, not chain) lashings.
If the goal was to increase the safety margin of the lashings; rather than try to “tune” the tightness of each lashing it would be more practical to simply use lashing gear with a higher working load limit.
To reduce the area on deck occupied by each car and the labour and time required for lashing and unlashing cars, it has been proposed by the author that in some conditions, cars on decks could be transported without lashing
The result is that their ultra-high superstructures and high car deck cargo placement make car carriers extremely ‘stability sensitive’ (i.e. highly susceptible to stability loss). As such, there is little or no margin for error and the continuous maintenance of adequate stability must always be at the forefront of their Master’s and Chief Officer’s minds
This makes it sound like the operation is always on the knife edge of capsize, stand up too quickly from the breakfast table and she might go over.
The Golden Ray had 8407 MT of cargo but only 2981 MT of ballast and 890 MT of F.O. Shouldn’t need a computer to determine that in that condition the stability has to be watched closely…
But the Golden Ray ballast tanks had a capacity of 10,088 MT, fuel oil capacity was over 4000 MT.
In this particular instance the Golden Ray would have required another 3000 tons of ballast for safe operation.
I probably don’t have to tell you but the easiest way to search for the word stability is to search in the page for this word. Here you get 61 hits which is quite considerable for a one page search.
Yes, I had a quick look at it, it’s an interesting article. They are calling ships under 200 meters PCTCs and over 200 Large Car Truck Carrier (LCTC).
I thought this was interesting.
Maybe there’s a better term for it but " operational envelope " comes to mind. That’s what’s being discussed here. The article from Maritime Mutual is claiming that PCTCs are constantly operated with very small margins and that it’s a consequence of the design of the vessel.
In view of all the attachments delivered above by all and obvious complexity of the problem I am just curious , what your( participants) comments may be on the G.R. master and ch/mate interviews. One sample below:
