Baltimore Bridge collapse

[RandomGuy99]

There's a few videos floating around, which  are interesting; as the ship approaches  the bridge,  all its lights go out. It drifts for  a bit, the lights come back on.  Thick black smoke starts billowing from the funnel, then all the lights go out again.

Very shortly thereafter, the impact  happens.

Apparently the black smoke was the emergency generator starting but it doesn't provide power for the engines or steering.

[daviemac]

There's a few videos floating around, which  are interesting; as the ship approaches  the bridge,  all its lights go out. It drifts for  a bit, the lights come back on.  Thick black smoke starts billowing from the funnel, then all the lights go out again.

Very shortly thereafter, the impact  happens.

Sounds like an issue with the axillary engine as that provides all the electrical power including that for the main engine fuel pre heating systems and that won't run on cold fuel.

[chrishornx]

There's a few videos floating around, which  are interesting; as the ship approaches  the bridge,  all its lights go out. It drifts for  a bit, the lights come back on.  Thick black smoke starts billowing from the funnel, then all the lights go out again.

Very shortly thereafter, the impact  happens.

that was the loss of power the ship had

[chrishornx]

I have to admit I didn't appreciate that the ship had a blackbox

that will be  a big help

[RandomGuy99]

They're probably all standing around scratching their heads now.

How do we get the ship out with sinking it?

How do we take the bridge apart.

The US government will be issuing some big contracts for water borne cranes and anyone that can use a torch cutter and or plastic explosives

They reckon it will cost $15M a day in lost ship traffic and there's 1000s of people who can't work without ship traffic.

[scutty brown]

Apparently the black smoke was the emergency generator starting but it doesn't provide power for the engines or steering.

Black smoke isn't a surprise for a ship's diesel starting from cold.
A lot of them run on heavy bunker oil - when the engine is warm but to start it up they often inject neat diesel or kerosene into the engine until it gets to running temperature. Cold two-stroke oil engine with mechanical scavengers isn't going to burn diesel very efficiently, it'll put out a heck of a lot of unburnt/partially burnt fuel through the exhaust until it gets warm

[RandomGuy99]

Black smoke isn't a surprise for a ship's diesel starting from cold.
A lot of them run on heavy bunker oil - when the engine is warm but to start it up they often inject neat diesel or kerosene into the engine until it gets to running temperature. Cold two-stroke oil engine with mechanical scavengers isn't going to burn diesel very efficiently, it'll put out a heck of a lot of unburnt/partially burnt fuel through the exhaust until it gets warm

They're also investigating if "dirty fuel" caused the engines to fail. To me it looks like someone just didn't check something before they left the dock.  It should be to find out as they had a black box on the ship.

Meantime they need to get cutting up the bridge ready to be hailed away then locate all the cars and haul them out with grabs.

[mr.bluesky]

As someone has posted on "X" surely large ships like this has back up systems in place in case of power failure/ steering failure.  If the ship was drifting towards the bridge structure not under power could they not drop anchor to bring it to a stop. 
It's also been said the ships crew could be stuck aboard the stricken ship for two weeks.

[chrishornx]

They're also investigating if "dirty fuel" caused the engines to fail. To me it looks like someone just didn't check something before they left the dock.  It should be to find out as they had a black box on the ship.

Meantime they need to get cutting up the bridge ready to be hailed away then locate all the cars and haul them out with grabs.

first of all they need to respectfully complete the search for bodies.

[RandomGuy99]

As someone has posted on "X" surely large ships like this has back up systems in place in case of power failure/ steering failure.  If the ship was drifting towards the bridge structure not under power could they not drop anchor to bring it to a stop. 
It's also been said the ships crew could be stuck aboard the stricken ship for two weeks.

They did drop an anchor but a ship like that isn't quick to stop

[chrishornx]

As someone has posted on "X" surely large ships like this has back up systems in place in case of power failure/ steering failure.  If the ship was drifting towards the bridge structure not under power could they not drop anchor to bring it to a stop. 
It's also been said the ships crew could be stuck aboard the stricken ship for two weeks.

they did have a back up system

they probably couldn't drop an anchor as they lost power and the momentum of a ship of that size and weight would mean it would not have had any real effect in time anyway

[scutty brown]

As someone has posted on "X" surely large ships like this has back up systems in place in case of power failure/ steering failure.  If the ship was drifting towards the bridge structure not under power could they not drop anchor to bring it to a stop. 
It's also been said the ships crew could be stuck aboard the stricken ship for two weeks.

Just watching an interesting analysis.
They did drop the front port anchor, though they needed power to release it. But that wouldn't stop the ship: soft bottom there, nothing substantive for the anchor to dig in to. In the event it seems all the anchor did was drag the ship around so it swung in the wind around the anchor chain, out of the main channel and into the bridge support. They may have been better off NOT dropping the anchor.

Another thing that came up in the report: with the bridge down, something like 10% of the USN Military Sealift Command is stuck in the harbour. If the same were to happen to two other ports, then the USA would be unable to support its military overseas. At the same time a large part of the USN itself would be trapped. A lot of American ports have equally vulnerable bridges.

[RandomGuy99]

Just watching an interesting analysis.
They did drop the front port anchor, though they needed power to release it. But that wouldn't stop the ship: soft bottom there, nothing substantive for the anchor to dig in to. In the event it seems all the anchor did was drag the ship around so it swung in the wind around the anchor chain, out of the main channel and into the bridge support. They may have been better off NOT dropping the anchor.

Another thing that came up in the report: with the bridge down, something like 10% of the USN Military Sealift Command is stuck in the harbour. If the same were to happen to two other ports, then the USA would be unable to support its military overseas. At the same time a large part of the USN itself would be trapped. A lot of American ports have equally vulnerable bridges.

Sounds like they'll get funding to fix that vulnerability.

It's also being by Trump to highlight immigration as the repair workers were from South America. That's mostly down to Americans not wanting to do that kind of work for the money being paid.

[scutty brown]

Some more things to think about........
with the Houthi problem causing issues at Suez, and low water in the Panama canal already forcing ships to take the "long way round" and so putting pressure on shipping capacity, taking (I understand) something like 40 container ships out of the equation, trapped, is only going to push freight costs sky high. And those ships that are already carrying stuff are going to end up in the wrong locations. What use is a consignment of Mercedes or Jaguars intended for Maryland if they get sent to Miami? Same applies to any other goods.
Our logistics are already strained, this is like another ratchet to stress the west even more. The absolute definition of asymmetric warfare - fuck your enemy in such a way that he doesn't even realise he's been targeted.

As for clearing the bridge and the sunken roadway, it seems all the Army Corps of Engineers has is a couple of dredgers, nothing to do the job with. Commercial kit is going to have to be hired in - heavylift cranes & barges. Finding divers to do the job is going to be tricky - diving in a fast flowing river with unorganized unmapped moving debris is going to be a safety nightmare

[RandomGuy99]

Some more things to think about........
with the Houthi problem causing issues at Suez, and low water in the Panama canal already forcing ships to take the "long way round" and so putting pressure on shipping capacity, taking (I understand) something like 40 container ships out of the equation, trapped, is only going to push freight costs sky high. And those ships that are already carrying stuff are going to end up in the wrong locations. What use is a consignment of Mercedes or Jaguars intended for Maryland if they get sent to Miami? Same applies to any other goods.
Our logistics are already strained, this is like another ratchet to stress the west even more. The absolute definition of asymmetric warfare - fuck your enemy in such a way that he doesn't even realise he's been targeted.

As for clearing the bridge and the sunken roadway, it seems all the Army Corps of Engineers has is a couple of dredgers, nothing to do the job with. Commercial kit is going to have to be hired in - heavylift cranes & barges. Finding divers to do the job is going to be tricky - diving in a fast flowing river with unorganized unmapped moving debris is going to be a safety nightmare

I heard the US Navy was going to provide some heavy lift cranes. It depends how big the bits are that they cut the bridge into. The US has plenty of divers on the rigs in the Gulf of Mexico and obviously the navy has divers too. I'm sure they're on it just like the clearance work after 9/11. They'll get the port working again ASAP.   The US naval base at Norfolk isn't far away.

[DastardlyDick]

they did have a back up system

they probably couldn't drop an anchor as they lost power and the momentum of a ship of that size and weight would mean it would not have had any real effect in time anyway

Many years ago, I knew a chap who was 1st Officer on a supertanker, and he said that even with both engines running at full astern, it would take about 5 miles to stop from "cruising speed". The big problem with going full eastern was that you lost all steering control, as no thrust was going over the rudder.

[covertlook]

The explanation:

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[scutty brown]

Many years ago, I knew a chap who was 1st Officer on a supertanker, and he said that even with both engines running at full astern, it would take about 5 miles to stop from "cruising speed". The big problem with going full eastern was that you lost all steering control, as no thrust was going over the rudder.

Something I hadn't realised until it was pointed out in one of the online shorts this week: if a ship goes straight from forward to reverse not a lot happens as all you get is cavitation around the propeller, there's no reverse thrust. You have to power off, shed speed through hull drag, and then go to reverse. Also when you do get power back again there's a natural tendency on a single-screwed ship for the hull to turn to one side against the force of the propeller, making steering lopsided.