Author Topic: Baltimore Francis Scott Key Bridge collapse  (Read 48210 times)

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Offline SeanB

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #100 on: March 28, 2024, 08:03:18 am »
Also to point out that those shipboard lights are high pressure sodium lights, which take 3 minutes to restrike when the power is interrupted. Cheap iron core and superimposed pulse starters will not strike a hot tube, until it has cooled down a little, when it will restrike, in about 3 minutes. I would also say the ship owners would also not buy dual tube lamps, where they have 2 arc tubes in parallel in the glass envelope, and which will, if there is a single power dip, have the other tube light up and run, as these cost double the price of the cheap Chinese Ya Ming lamps they likely buy by the case lot. The lights going out is a good indication of power loss, but the relight shows the hot restrike time, and they all coming on nearly at the same time says they were all from the same batch, and all had similar running hours on them, as the restrike time varies greatly with age, and from batch to batch. The only way to have hot restrike is to buy more expensive ballasts that can provide the 5kV plus needed to strike the tube, which needs the wiring to be insulated to the socket, and the socket to be rated for 5kV without flashing over, plus the tubes need a different E40 base design with a wider glass insulator.

No LED lights, the power supplies fail badly, even those designed for rough service use, and do not mix well with salt water ingress, while the magnetic will carry on till the core rots away. Also easy to relamp, as all you need to carry up in a small sling bag is a spare lamp, a new ignitor, a can of WD40 for the rusted fasteners, and some pliers and screwdrivers to open the fixture, which mostly use simple spring clips to allow tool less lamp changes. LED you have to use a rope and pulley to first lower the old one down, and then pull the new one up, and need 2 people up there, and 2 on deck, to do this. Lamp just needs one person and possibly a deck watcher for the crew of 3, doing 3 at a time in an area. Plus also 5 minutes per lamp, excluding the climb, and power does not have to be cut either.
 
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Offline Someone

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #101 on: March 28, 2024, 08:42:11 am »
At least it's not on fire.
Yet/so-far.
Why would you expect this to happen, given that no indications so far point towards anything even distantly fire-related. The Dali is now at rest, and ships at rest don’t normally just burst into flame.

The two sources of smoke initially reported by some have since been explained: the black smoke is from the engines, and the “smoke” at the point of impact is concrete dust, isn’t it?
Mostly in jest, but grounded ships have subsequently caught fire in the past so its not implausible.
 

Offline Circlotron

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #102 on: March 28, 2024, 11:50:08 am »
And a fraction of the size of the biggest ships today, which currently top out at 24,000 TEU!
That's twelve thousand large truck's worth! Yowsers!
 
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Offline floobydust

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #103 on: March 28, 2024, 06:45:15 pm »
At least it's not on fire.
Yet/so-far.
Why would you expect this to happen, given that no indications so far point towards anything even distantly fire-related. The Dali is now at rest, and ships at rest don’t normally just burst into flame.

The two sources of smoke initially reported by some have since been explained: the black smoke is from the engines, and the “smoke” at the point of impact is concrete dust, isn’t it?

Cargo manifest shows 56 containers of hazardous (764 tons) mostly corrosives, flammables, "Class 9 including lithium-ion batteries" according to the NTSB Media Briefing 2.
Containers are flattened, crushed. Some in the water, some are leaking. There's around 4,700 on the ship.

It's not a static situation, tides up and down and things have to be moved, torched cut as they clean up the mess.
I would say there is a fire risk- but putting it out is the impossibility if one starts. The bow has a huge hole in it.
 

Offline tooki

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #104 on: March 28, 2024, 06:57:44 pm »
At least it's not on fire.
Yet/so-far.
Why would you expect this to happen, given that no indications so far point towards anything even distantly fire-related. The Dali is now at rest, and ships at rest don’t normally just burst into flame.

The two sources of smoke initially reported by some have since been explained: the black smoke is from the engines, and the “smoke” at the point of impact is concrete dust, isn’t it?
Mostly in jest, but grounded ships have subsequently caught fire in the past so its not implausible.
I said ships do not normally catch fire, not that it's impossible.

And it's not grounded, mind you. The ship is afloat.
 

Offline tooki

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #105 on: March 28, 2024, 06:58:53 pm »
Cargo manifest shows 56 containers of hazardous (764 tons) mostly corrosives, flammables, "Class 9 including lithium-ion batteries" according to the NTSB Media Briefing 2.
Containers are flattened, crushed. Some in the water, some are leaking. There's around 4,700 on the ship.

It's not a static situation, tides up and down and things have to be moved, torched cut as they clean up the mess.
I would say there is a fire risk- but putting it out is the impossibility if one starts. The bow has a huge hole in it.
Definitely not impossible. But no reason to assume it's a likely outcome.
 

Offline coppercone2

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #106 on: March 28, 2024, 07:08:37 pm »
a container full of massagers might turn on and cause the entire situation to shake apart
 
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Offline Sal Ammoniac

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #107 on: March 28, 2024, 07:24:48 pm »
This fuel at room temperature is a tar like substance and is heated to decrease its viscosity. It is then run through centrifugal separators to get rid of impurities prior to being fed to the engines

One theory that I've seen, that sounds plausible, is that contaminated fuel clogged the fuel filters for the generators, causing the generators to stop. Perhaps the ship didn't have centrifugal separators, or the separators didn't filter out enough impurities to prevent clogging the filters.

The bunker oil used as fuel on ships like this one is the dregs of the petroleum refining process and often contains gunk that may be problematic.

All of this should be easy enough to figure out as the ship is still intact and presumably there's data logging that will point to the cause of the problem.
"That's not even wrong" -- Wolfgang Pauli
 

Offline tooki

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #108 on: March 28, 2024, 07:44:26 pm »
All of this should be easy enough to figure out as the ship is still intact and presumably there's data logging that will point to the cause of the problem.
Yep. The NTSB has already taken the data recorder. However, we may end up disappointed with what it contains, or rather doesn't.

This is what the NYT reported:
Quote
Jennifer Homendy, the N.T.S.B. chair, says the agency has long wanted more data to be recorded on ships’ voyage data recorders. She described the apparatus as recording only basic data, far less than is the case with the recording devices — or “black boxes” — on commercial airplanes.

N.T.S.B. officials said the voyage data recorder on the ship was a newer model, with additional features, but is still “very basic” compared to what would be on a commercial airplane. It does not, for example, record power distribution data, they said. However, it does record the ship's location, rudder commands and audio.
 

Online tom66Topic starter

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #109 on: March 28, 2024, 09:14:06 pm »
It should be easy enough to examine parts of the engines, generators, fuel and fuel system to determine the likely fault.  Chances are, if they powered the ship up in this configuration they'd be able to replicate the fault too, if it's related to a problem that exists there rather than crew misoperation.

It sounds like from another NTSB report that the data recorders are only operational when the main ship power is running, so they likely only recorded data when things were operating correctly.  The audio recorders, however, do operate off backup batteries, and so they've retrieved the audio from the ship's bridge for the duration of the incident.
 

Offline Someone

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #110 on: March 28, 2024, 10:55:05 pm »
At least it's not on fire.
Yet/so-far.
Why would you expect this to happen, given that no indications so far point towards anything even distantly fire-related. The Dali is now at rest, and ships at rest don’t normally just burst into flame.

The two sources of smoke initially reported by some have since been explained: the black smoke is from the engines, and the “smoke” at the point of impact is concrete dust, isn’t it?
Mostly in jest, but grounded ships have subsequently caught fire in the past so its not implausible.
I said ships do not normally catch fire, not that it's impossible.

And it's not grounded, mind you. The ship is afloat.
Equally I'm not saying it will catch on fire in the future for certain. yet/so-far both leave either possibility for the future and literally mean "up to the current time".

As to grounded, if it cant move as its tangled in things sitting on the riverbed, that mass/agglomeration of which the ship is a part is grounded.
Wikipedia references bringing the goods:
https://maritime-executive.com/article/bridge-s-weight-is-pinning-container-ship-dali-to-the-bottom
Quote
In a reversal of the usual order for a major marine salvage operation, the U.S. Army Corps of Engineers (USACE) and its contractors will make the first big move in getting the wrecked container ship Dali out of Baltimore's ship channel.

Dali's bow is technically aground in the channel, said Vice Adm. Peter Gautier at a press conference Wednesday, because of the vast weight of the steel bridge span resting on top. The ship is pinned to the bottom and cannot move.
« Last Edit: March 28, 2024, 10:59:11 pm by Someone »
 

Offline Andy Chee

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #111 on: March 28, 2024, 11:40:36 pm »
And it's not grounded, mind you. The ship is afloat.
Not with the weight of a broken bridge span sitting on the deck of the bow!

I’ll be fascinated with the salvage operation. Much like the refloating of Costa Concordia, they’ll have to be careful about weight and buoyancy shifts.
 

Offline coppercone2

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #112 on: March 29, 2024, 01:17:22 am »
let people claim containers as salvage and it will be gone in 3 days


However the value of a good failure analysis could benefit us for the next 100 years if they figure out every detail and determine how to make improvements
 

Offline Andy Chee

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #113 on: March 29, 2024, 01:49:10 am »
Once enough debris has been manually cleared from the ship’s bow, the ship refloated and towed away, the remaining bridge span elements, both above and below water, will probably be broken down into smaller pieces by demolition explosives.

The bridge is way too big to cut apart with plasma torches or oxygen lances.

The ship itself is also probably destined for scrap metal yard.
« Last Edit: March 29, 2024, 01:51:23 am by Andy Chee »
 

Offline floobydust

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #114 on: March 29, 2024, 01:54:02 am »
Keep the ship for collateral - some 1851 law which was cited by the Titanic’s owner in a Supreme Court case 1912, could limit the payout. Titanic law could help ship owner limit liability in Baltimore bridge collapse

Estimates are $2B to repair/replace the bridge, $0.1B to free the ship and clean up the mess. Biden is talking like the Feds will give the money, but I have to ask why the US taxpayer is ultimately on the hook, as well as the many years of cranked up toll pricing we know will result. OUCH.
 

Offline Andy Chee

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #115 on: March 29, 2024, 02:06:07 am »
Keep the ship for collateral - some 1851 law which was cited by the Titanic’s owner in a Supreme Court case 1912, could limit the payout. Titanic law could help ship owner limit liability in Baltimore bridge collapse

Estimates are $2B to repair/replace the bridge, $0.1B to free the ship and clean up the mess. Biden is talking like the Feds will give the money, but I have to ask why the US taxpayer is ultimately on the hook, as well as the many years of cranked up toll pricing we know will result. OUCH.

Recouping the costs from the “at fault” parties, will probably take a long time in courts, longer than if the US government financed the rebuilding from the start.

The US government can always recoup the costs later.
 

Offline xrunner

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #116 on: March 29, 2024, 02:06:26 am »
Oh yea Money Money Money (I'm humming the song from Dark Side of the Moon in my head at the moment). Of course we have lessons learned from the collapsed bridge, so they'll design the new one to withstand such a crash better. Maybe more lanes? How about restaurants and shopping areas at the entrances. The list goes on ...  :-DD
I told my friends I could teach them to be funny, but they all just laughed at me.
 

Offline coppercone2

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #117 on: March 29, 2024, 02:45:24 am »
Oh yea Money Money Money (I'm humming the song from Dark Side of the Moon in my head at the moment). Of course we have lessons learned from the collapsed bridge, so they'll design the new one to withstand such a crash better. Maybe more lanes? How about restaurants and shopping areas at the entrances. The list goes on ...  :-DD

I think you should put them on the bridge. Like the original london bridge.

I think you are going here with your idea.


You could buy all sorts of services on it. From the late seventeenth century there was a greater variety of trades, including metalworkers such as pinmakers and needle makers, sellers of durable goods such as trunks and brushes, booksellers and stationers.[18]


How about a drive through chapel?
« Last Edit: March 29, 2024, 02:47:46 am by coppercone2 »
 

Online SiliconWizard

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #118 on: March 29, 2024, 03:02:11 am »
let people claim containers as salvage and it will be gone in 3 days

I know it's just tongue-in-cheek, but just for the sake of the idea, how would people salvage all this in 3 days right in the middle of the river with no bridge?
 

Offline themadhippy

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #119 on: March 29, 2024, 03:40:52 am »
Quote
how would people salvage all this in 3 days right in the middle of the river with no bridge
canoes
 

Offline floobydust

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #120 on: March 29, 2024, 03:58:36 am »
Given $xx million to get this ship out of the way, how are we doing it? FAST

Use Thug Technology® - wait for high tide, maybe a Supermoon - startup the ship's engine and nail it in reverse!
Use TNT and blow up that pier!
I could borrow my uncle's tugboat, maybe call up his friends and get their tugs pushin' too.

Remember the Suez Canal incident March 2021? Ever Given ran aground. It's over 2x GT as big as the MV Dali (but similar engine power, odd). Call up SMIT Salvage has a huge crane and tugs. Bloomberg story

The Francis Scott Key bridge also got nailed in 1980 by (smaller) container ship named the Blue Nagoya. Good to know nothing was changed.
 

Online SiliconWizard

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #121 on: March 29, 2024, 04:10:59 am »
Quote
how would people salvage all this in 3 days right in the middle of the river with no bridge
canoes

Yes. ;D
(Just for some figures, a 400m container ship holds an average of 20,000 TEU ( https://en.wikipedia.org/wiki/Twenty-foot_equivalent_unit ), it's hard to give an equivalent weight of course, but it's usually about 20T per TEU.
So, that's about 400,000T for the whole ship. And, of course, in containers piled up on several layers.
All that in 3 days on some canoes. :-DD )
 

Offline mfro

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #122 on: March 29, 2024, 07:17:05 am »
Stick a $10000 tag on each container and they will be gone by tomorrow.
Beethoven wrote his first symphony in C.
 

Offline coppercone2

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #123 on: March 29, 2024, 08:06:40 am »
I think they would form a fleet of various boats from all over the place in american east coast to take it on anything they can
 

Offline Jeroen3

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Re: Baltimore Francis Scott Key Bridge collapse
« Reply #124 on: March 29, 2024, 08:21:12 am »
Given all the difficulty of having to match phases, wouldn't HVDC make more sense nowadays? And/or just stick to hydraulics for the big mechanical stuff?
Yes and no. Matching phases is easy, we're doing for decades. The gear is there, you can buy DEIF, Woodward, Deep Sea controllers for it. Standard gear. DC is not standard. It requires inverters, and those are complicated and dangerous. They require complex control theory and software. Where you can manually keep spinning copper in check if you have to.

However it is attempted. DC busses or having a few drives on DC bus is attempted at some ships. I know of a large ferry and some youghts but inverters do not play not nice with good old spinning copper and iron. Plagued with problems and breakdowns.
Inverters can do things generators cannot keep up with, not engine wise, not control wise and not due to reactances, complicated physiscs.
 


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