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Baltimore's Key Bridge struck by cargo ship, collapses

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Re: Baltimore's Key Bridge struck by cargo ship, collapses

#611

DALI (IMO: 9697428) is a Container Ship and is sailing under the flag of Singapore. Her length overall (LOA) is 299.92 meters and her width is 48.2 meters [1]. Based on the track, it appears the ship changed course slightly and slowed as it approached the bridge [2]. [1] https://www.marinetraffic.com/en/ais/details/ships/shipid:28... [2] https://www.marinetraffic.com/en/ais/home/shipid:2810451/zoo...

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Re: Baltimore's Key Bridge struck by cargo ship, collapses

#612
post #603

Earlier quoted context omitted.

Was there a harbor pilot on board, or the normal ship pilot? Were there tug boats helping with the exit? I have often felt that the harbor protocols were overkill, but this is one of the times they could have helped.

Once the ship is under way I don't think the tugs hang around. They are just for the push away from the dock and initial turns.

It's very typical for pilots to be required for all entrance and egress from harbors, much more than the initial pushaway and turning but for quite a long distance through the channel.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#613

Youtube tracking analysis from a knowledgeable mariner. He says that at about 1:24 AM the ship loses power (from video feed) while traveling 8.5 knots. at 1:25.30 power is restored. at 12:25.59 the ship shows smoke. The ship has already drifted in the channel. It is believed that at this time the ship applied full reverse power as evidenced by the black smoke. (My analysis: the ship drifted but hasn't turned in the c…

I'm once again impressed that subject matter experts are out there on every topic, and they are often capable of quickly and accurately disseminating information about an event far better than the local news.

[deleted]

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#614

Earlier quoted context omitted.

They keep reporting this, and maybe it was because the video was sped up, but it looked like there was still traffic going across until very close to the collision

The last car crossing that I can see clears the span about 1:28:06; the bridge collapses about 1:28:48. That's about 40 seconds of gap between the traffic and the collapse. I haven't timed how frequently cars are coming, but it seems to be about every 30 seconds or so, which--combined with the time it takes to cross the bridge--is evidence that a bridge closure was effected just before the bridge collapse.

If the police were able to close the bridge just in time, that's a pretty spectacular response. There were only ~5 minutes between the ship loosing power initially and the impact. The police saved lives, and it's only a shame that the construction crew wasn't evacuated in time.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#615

Somehow I find it surprising how completely the bridge collapsed after the damage. I understand that a container ship collision is serious, but you could imagine a scenarios where the bridge slumps or buckles but doesn’t just disintegrate like that. It’s surprising that ships capable of doing this damage were probably regularly driving past it, and its safety as a thoroughfare depended entirely on those collisions no…

That bridge looks like its almost entirely made of just trusses. It's hard to imagine how one might expect it not to collapse when everything holding it together is so thin.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#616
post #573

Earlier quoted context omitted.

I'm not sure what configuration of props a ship like this has, but in my experience with a 40ft sailboat with a single propeller you have absolutely no rudder authority while reversing. I've read that some large ships also are direct drive--there's no transmission between the engine and the propeller, so "reversing" (if it's even possible) entails shutting down the engine and restarting it in reverse. This can be don…

> in my experience with a 40ft sailboat with a single propeller you have absolutely no rudder authority while reversing. In general it depends on the rudders and the boat. Longer keeled boats don't respond well in reverse at all but more modern boats (like mine, 1990) will do better but will still need some way to have steerage. I can certainly manouver around the marina in reverse, it's just harder than forwards and…

Going backwards in the marina I often steer on the engine rather than the rudder (though I keep the rudder aligned with the engine of course). Obviously that's in a tiny sailing boat with an external engine, but I thought large ships also often have a steerable front propeller to assist with steering and mooring. Although maybe these very large ships use tugboats for that.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#617

Youtube tracking analysis from a knowledgeable mariner. He says that at about 1:24 AM the ship loses power (from video feed) while traveling 8.5 knots. at 1:25.30 power is restored. at 12:25.59 the ship shows smoke. The ship has already drifted in the channel. It is believed that at this time the ship applied full reverse power as evidenced by the black smoke. (My analysis: the ship drifted but hasn't turned in the c…

I'm once again impressed that subject matter experts are out there on every topic, and they are often capable of quickly and accurately disseminating information about an event far better than the local news.

> event far better than the local news.

That’s such a ludicrously low bar that I’m not even sure this would qualify as a compliment to these alternative producers.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#618
Let’s say you had infinite money and no paperwork filings required. What is the fastest possible timeline in which a replacement bridge could be designed and completed?

Just removing the detritus of the current bridge sounds like a multi month affair.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#619

Youtube tracking analysis from a knowledgeable mariner. He says that at about 1:24 AM the ship loses power (from video feed) while traveling 8.5 knots. at 1:25.30 power is restored. at 12:25.59 the ship shows smoke. The ship has already drifted in the channel. It is believed that at this time the ship applied full reverse power as evidenced by the black smoke. (My analysis: the ship drifted but hasn't turned in the c…

How common are power outages on ships? I get that the captain might not have responded to it correctly but that seems like a thing that shouldn't happen, at least in my completely uneducated opinion.

We had a 100-200 car ferry here in Seattle lose power and run into an island last year.

I think it was something like bad fuel killing the generator.

Re: Baltimore's Key Bridge struck by cargo ship, collapses

#620

Youtube tracking analysis from a knowledgeable mariner. He says that at about 1:24 AM the ship loses power (from video feed) while traveling 8.5 knots. at 1:25.30 power is restored. at 12:25.59 the ship shows smoke. The ship has already drifted in the channel. It is believed that at this time the ship applied full reverse power as evidenced by the black smoke. (My analysis: the ship drifted but hasn't turned in the c…

Can anyone say if there is the slightest possibility that this was caused by an Cyber attack?
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