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According to this book: https://www.amazon.com/Tankship-Tromedy-Impending-Disasters-Tankers/dp/0977647900 https://www.amazon.com/Tankship-Tromedy-Impending-Disa
by jordanb 3y ago
According to this book: https://www.amazon.com/Tankship-Tromedy-Impending-Disasters-Tankers/dp/0977647900 https://www.amazon.com/Tankship-Tromedy-Impending-Disasters-...
It is quite common and vessels often have outages that leave them Not Under Command. Usually they are safely at sea when this happens and they can drift for hours without causing problems. But of course there's always a possibility of it happening at exactly the wrong moment.
The reasons for this are the usual: lack of redundancy, lack of maintenance, overworked and understaffed crews, etc. etc. The book lays out how ships are pretty much designed to be floating disasters and the Class societies (essentially privatized regulators) are in the pockets of the builders, and they are so captured that they make rules that make it difficult to make safe vessels.
For instance, he was trying to design multi-screw vessels but the rules now assume single-screwed ships and it can be impossible to design in additional shaft alleys and still conform.
- ianburrell 3y agoIt wouldn't help with this accident, but you would think that the electronics would be on batteries. It wouldn't be too hard to have rack of batteries that would power the lights, instruments, radios, and sensors. Doesn't help if the propulsion or steering go out, but does make easier to know whats going on.
- myself248 3y agoAt least in small craft, bow thrusters are usually electric, with local batteries charged from the main engine room. I don't know what large craft are like, but it doesn't seem unreasonable that a bow thruster may remain operable even if the main engine fails. Clearly that's not required or they would've had it and used it, but it could be required if the regulations didn't suck. Furthermore, steering could absolutely have an electric backup for the hydraulic pumps that power the main steering gear. As long as there's some forward speed through the water, the rudder should work. But again, backups clearly aren't required or they would've worked here. Steer-by-wire cars are required to have all sorts of redundancy so they're almost as safe as steering-shaft cars in case of an engine failure. This is a 9,900TEU ship with a 41480 kw powerplant. That a ship with so much more destructive potential is allowed to operate without the same level of redundancy as a $90k Audi, is unconscionable.
- paddy_m 3y agoThe difference for a car and drive by wire system is that the failure mode of control systems on cars is normally catastrophic and dangerous. If a car loses steering or brakes, it will hit something within seconds 95% of the time. That ship spent 1 (4:30 to 5:30) hour of a presumably 10-20 day voyage in a critical control section. The tugs left the ship right around 5:08 (43 seconds into the video). A much better policy for this case would be to have required the tugs stay with the boat until it passed the main span safely. There were no doubt maintenance issues that led to this accident, but it is exceedingly rare for these types of failures to cause this type of catastrophic result.
- ClumsyPilot 3y agoDamage is less likely, but much more destructive. Same as for a nuclear reactor. It’s not clear why adding ~$100k to the cost of a billion dollar ship is unreasonable
- throwup238 3y agoAircraft carriers are billion dollar ships, these are not. The most expensive container ship tops out at ~$250 million and the one that crashed today is more like $80-150 million. The propulsion systems on these vessels cost tens of millions. $100k wouldn't even pay for the material costs of a rudder. I don't know enough about the cost and safety tradeoffs made in the design of these ships to comment but your numbers are orders of magnitude off from both directions.
- Turing_Machine 3y agoRight. It's not like the ship owners (or, more saliently, their insurers) want things like this to happen. Second-guessing the marine engineers in this case is like the people post-9/11 who argued that future buildings should be designed to withstand the impact of a wide-body jetliner fully loaded with fuel. It's basically not a serious argument.
- jordanb 3y agoThe problem is with steering. The rudder on a ship this big is going to be wall of steel several stories tall with gears as big as car. Warships have several independent backup steering options reducing finally to a worm gear at the top of the shaft with a winch handle big enough to put a gang of men on it. But ships like this will have none of that. They will have a small wheel or joystick on the bridge and if power goes out the rudder will definitely stay in the last commanded position until power is restored. Even if they had auxiliary steering they would not have the crew to man those positions. This ship would have alternate diesel power plants called "mules" (think APUs on aircraft). It's possible that when the lights came back on that was because they got a mule started. But really if we don't want accidents like this to happen the ship should have redundancy. A 10,000 TEU container ship is one of the largest and heaviest moving structures ever created by man. Why is it acceptable that it is driven by exactly one engine powering one screw in front of one rudder? By the way a ship this big with only one screw is very difficult to maneuver at slow speeds. They pretty much have to be going at least 14-15knots to have any rudder authority.
- ViewTrick1002 3y agoEmergency steering gear is required on every commercial vessel and is regularly tested. We will have to wait for the investigation to see what actually happened.
- mlyle 3y ago> But really if we don't want accidents like this to happen the ship should have redundancy. A 10,000 TEU container ship is one of the largest and heaviest moving structures ever created by man. Why is it acceptable that it is driven by exactly one engine powering one screw in front of one rudder? Perhaps because we have a whole lot of them going and a very low frequency of events like this. Maybe there's some lighter weight interventions we could do that would further halve the risk of something like this happening that are less costly than fully redundant engine and drive. They're supposed to have emergency steering gear. Why didn't it work? Maybe ships should have an auxiliary genset running while near land.
- 3y ago
- bmitc 3y agoThanks for the link to that book. I don't know if it's the because of this catastrophe, but it looks to be unobtanium at the moment. Will have to find it in the library. > lack of redundancy This is what I am surprised at from many angles. It seems to me that the ship, the port (in the form of lack of tugboats), and the bridge (in the form of lack of secondary protection of the pillars) all had a lack of redundancy and secondary options.
- jordanb 3y agoThe author GPLed it and put it on the internet at one point: http://martrans.org/documents/2006/safety/The%20_tankership_tromedy.pdf http://martrans.org/documents/2006/safety/The%20_tankership_...