Francis Scott Key Bridge collapse

[Harry]

There were only 2 bridges of this exact design ever made. One was the Tacoma Bridge, in this video. The other one is the Deer Isle Bridge, in Maine. That one's still in use, I've been over it dozens of times and that is one shaky motherfucker.

Huh? The bridge in your video is a suspension bridge while while the bridge in Baltimore is a cantilever. That is about as far from an “exact design” as you can get. Not even close, you can’t even call them a similar design.


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[ötzi]

Random bridge disaster, nothing to do with Baltimore except bridge fall down.

[Cisco Kid]

So it's a continuous truss bridge. Same design as the bridge that fell a few years ago. They go down like a house of cards.

Continuous Truss for the win? I took my girlfriend out onto a Continuous Truss bridge before it opened to neck.

[bennymac]

Continuous Truss for the win? I took my girlfriend out onto a Continuous Truss bridge before it opened to neck.

right….because of the implication

[JimmyCarter]

“Ahhh there’s nowhere for me to run! What am I gonna do, say no”


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[MagnificentUnicorn]

Haven't you seen the Wire?
PO LEECE can clear a corner in 5 minutes.

They probably heard that Omar was coming


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[BmillsSkier]

right….because of the implication

“Ahhh there’s nowhere for me to run! What am I gonna do, say no”


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Do I sense the D.E.N.N.I.S. Method at play here?

[east or bust]

Huh? The bridge in your video is a suspension bridge while while the bridge in Baltimore is a cantilever. <snip>

The Baltimore bridge is (was) a continuous truss as cisco kid said

[truckeelocal]

Panama Canal requires constant tug usage because of the potential cost of the canal going out of use due to an incident. Guess Baltimore Harbor isn't that important ? We'll see when we can't get our German imports.

[Cisco Kid]

C'mon, who doesn't find this romantic? I think I got to 2nd base on that bridge.

[ötzi]

Panama Canal requires constant tug usage because of the potential cost of the canal going out of use due to an incident. Guess Baltimore Harbor isn't that important ? We'll see when we can't get our German imports.

The harbor's a little wider than the canal. And the German car import dock is outside the collapsed bridge (at Sparrows Point) and should be unaffected.

[2nd mate]

Huh? The bridge in your video is a suspension bridge while while the bridge in Baltimore is a cantilever. That is about as far from an “exact design” as you can get. Not even close, you can’t even call them a similar design.


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The sister bridge was in Bucksport Maine. Drove over it many times coming from and going back to school.

[2nd mate]

I last went under this bridge in 2022. No tugs made fast until after we went under the bridge n our way inbound. On the way out the tugs dropped lines as soon as we left the inner harbor and were steadied up headed out.
The word is the Maryland Pilot on the ship immediately notified someone to stop bridge traffic as soon as the ship blacked out. The Pilot indicated a steering loss with potential to hit the bridge. They certainly train for these scenarios in the simulators at Mitags.

The big questions will be:

Why did the ship loose power?
Did the ship try to make it through the span using ahead power, or stop the ship with an astern bell when steering and propulsion were restored?
Was one of my classmates the Pilot[emoji15]

The VDR will provide answers very shortly. The NTSB said they already had a team on hand to retrieve the data.
Moving forward most US ports that dont already require a tug to be made fast while transiting under a bridge, soon will.

[mud]

There was still a lot of traffic before it hit.



https://youtu.be/tPpBBRH-068?si=4pfCgljbIUiOtum7

[ötzi]

Man they stopped it just in time, that last guy barely made it

[BmillsSkier]

Panama Canal requires constant tug usage because of the potential cost of the canal going out of use due to an incident. Guess Baltimore Harbor isn't that important ? We'll see when we can't get our German imports.

Brunswick, GA will continue to bring in German imports (to the extent not already being made here in the US and being shipped out from there and CHS.)

[mud]

Those folks filling potholes never had a chance. Falling hundreds of feet trying to grasp what’s happening then hitting the water. And if that didn’t knock you out a shiton of steel is falling all around you. RIP

[bennymac]

^indeed. RIP. That’s a scary fucking way to go.

Someone mentioned the Wire - here’s a good view of how giant that bridge was

[skiballs]

Drove that bridge 100’s of times.
It was kinda weird turning on the tv, the first thing on was a video of the collapse, and instantly knowing which bridge it is/was.


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[Core Shot]

Clearly power loss. And full astern once power came back. Forward speed reduced significantly. But not enough.

[jono]

Basic back of the envelope...:

Momentum is "mass in motion." ....

counterintuitive how much energy ...

Also, all those equations without knowing dV?

[MagnificentUnicorn]

Man they stopped it just in time, that last guy barely made it

Well that was a time lapse video


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[MultiVerse]

Also, all those equations without knowing dV?

I thought showing it in two steps as a change in momentum expressed it better than simply as force or kinetic energy. The main takeaway is it's very hard to design a pillar that can withstand direct impact from a massive cargo ship, hence the use of dolphins etc. to redirect or stop a ship before impact. It needs to solve for the kinetic energy that needs to get dissipated, and/or there's also a huge amount of momentum that needs to be partly overcome to redirect it. For comparison:

Ship KE = 0.5 * (100000tons) * (7 knots)^2 = ~7e8 J
747 KE = 0.5 * (510,000 lbs) * (560 mph)^2 = ~7.25e9 J
747 avg weight = (MTOW + OEW) / 2 = ~510,000 lbs

[skibrd]

I last went under this bridge in 2022. No tugs made fast until after we went under the bridge n our way inbound. On the way out the tugs dropped lines as soon as we left the inner harbor and were steadied up headed out.
The word is the Maryland Pilot on the ship immediately notified someone to stop bridge traffic as soon as the ship blacked out. The Pilot indicated a steering loss with potential to hit the bridge. They certainly train for these scenarios in the simulators at Mitags.

The big questions will be:

Why did the ship loose power?
Did the ship try to make it through the span using ahead power, or stop the ship with an astern bell when steering and propulsion were restored?
Was one of my classmates the Pilot[emoji15]

The VDR will provide answers very shortly. The NTSB said they already had a team on hand to retrieve the data.
Moving forward most US ports that dont already require a tug to be made fast while transiting under a bridge, soon will.

Another second mate here, hopefully chief mate this year…

I’ve been going in and out of Oakland CA for years (APL and Pasha) and we don’t take a tug until after the Oakland Bay Bridge inbound and as soon as we are clear of the channel out bound. I can see the Port of Baltimore requiring an escort tug for a while, but not forever.

I saw a picture of the Dalt hitting the dock in Turkey in 2016, and heard they have had other generator issues in the past 12 months. What I’m wondering is who the classification society is, have they been documenting the generator issues, and what was done in the past? Also, will this be the wake up call that conditioned based maintenance is not safe?

I checked and both of my classmates that are Maryland Pilots were not the pilot on the Dalt.


Please feel free to ask any ship related questions, I’m sure 2nd Mate or I would be able to answer to clear up any confusion, and there is a lot of that out there right now.

As for the “dolphins” the Dalt missed, those are actually towers for power lines to go over the harbor, they are not the dolphins that are used to protect bridges.

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[MultiVerse]

Two questions: 1) Contaminated fuel possibly caused the engine failure? In the past, sulfur in fuel dissolved contaminates but the switch to low sulfur fuel is now causing more engine failures? 2) How practical are tugs to protect bridges? Tugs are a limited resource, right? So using tugs more would considerably slow down port operations?