No, me neither, and I’ll be interested to hear what they have to say. I assume in a couple years there will be a Well There’s Your Problem episode about this with 30 minutes of insightful engineering analysis and 90 minutes of wisecracks 
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This is a longer video that starts earlier and shows the time leading up to the impact. Warning, prior to the collision you can you see traffic on the bridge.
It appears that the ship lost power twice. Once when starting a turn, and then again when it should have been correcting for the drift from the first power loss. It impacted a main support pier for the main center span.
The bridge is an arch truss support bridge. Similar to other bridges with a center arched support span, the bridge is effectively a cantilever balanced support on either side of the main piers. If you picture it as 4 sections, the left of the left pier is balanced with the right of the left pier, the left of the right pier is balanced with the right of the right pier, and the left and right center sections are pushing against each other. The arch provides the support for the center sections against each other and the outer spans are all in balance. Beyond either of those sections on both sides are plain elevated roadway sections.
When the ship collided with the left pier, this destroyed the support for the left of left pier and right of left pier sections. The further left elevated roadway did not fall as the left section broke away from it. As both sections supported by the left pier fell, the left of right pier section falls as the arch support it was pushing against is no longer pushing back. The right of right pier section has a delayed reaction when the side providing balance to it is no longer proving that balance and falls. The elevated roadway to the right of that section did not fall.
The center arch and those 4 sections being in balance is fundamental to this bridge design. A suspension bridge while using a different mechanism would function much the same way if a main support was compromised. As compared to say a cable-stayed bridge which might act like two different spans that just meet in the middle but don’t support each other.
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When you got that much mass behind you, you don’t have to be going too fast to do some serious damage hitting something.
Still, you would think they would have some protective structures around the supports. Or maybe they weren’t enough.
Crazy stuff. Will be interesting to see how they replace, that is a big bridge. Let us flex some engineering marvels.
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Nope. Which was why it came down pretty much the same it would have in a controlled demolition. It’s just the way the overall static system was designed. Which wasn’t inherintly unsafe or anything as such. Thus was a load case it was never designed for, not even close. (Not that neglecting any construction ever improved its stability.)
Changing the overall static system is basically a complete rebuild. And then you might as well go all in with a suspension bridge with the pylons on dry land.
Alternatively, fucking protect the poylon(s) against ramming like they did at the Golden Gate bridge.
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“According to Gov. Wes Moore, a “mayday” call was made by the ship, which in turn allowed authorities to stop cars coming onto the bridge.”
He said the ship was coming in at eight knots, “a very rapid speed.”
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An noteworthy effect on road traffic:
The real disruption will be for hazardous materials, which cannot be transported via I-95 or I-895, the Baltimore Harbor Tunnel.
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Holy shit. Watching that, it seems like a miracle if truly only 7 people are missing.
What a disaster.
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Washington Post Gift link to the story stream.
Some key notes:
- Ship sent a mayday signal.
- They were able to stop some traffic based on the mayday, minimizing the vehicles on the span.
- Six of eight workers who were repairing the roadway are still missing. (At 10:40 AM)
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Thank goodness this happened at night, instead of during a rush hour or something.
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I didn’t read far enough. One more key item:
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That video that the media is using is sped up quite a bit.
Here’s the normal speed form the source.
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You might as well be measuring it in Warp Speed, because while I understand the theory behind knots, I have no idea how fast that is in reality.
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8knots= 9.206236mph
It’s fast for a loaded ship that size in the outgoing channel IMO.
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8 knots = 9.2 mph
8 knot = 1.3728015651e-8 speed of light [vacuum]
Sorry, don’t have warp speed on my converter.
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I live on an international shipping lane. The speed limit is 12 knots for freighters.
In the video that I posted, that’s real time, it does not appear to be going 8 knots.
Seeing the real time footage, I was surprised how slow it was going.
I can’t guess but it sure appeared to be going slower than 8 knots.
The sped up footage everyone is using it does appear to be going fast.
I have not seen any coverage noting the video was sped up.
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Yeah like someone said the kinetic energy is a function of speed multiplied by mass. Like how a fast-moving bullet might create damage on the same scale as a comparatively slow-moving sledgehammer.
A fully loaded cargo ship makes for one helluva big hammer.
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For the less patient, start viewing at about 5:20. Impact is at 5:30 but you get lead-up.
“According to Gov. Wes Moore, a “mayday” call was made by the ship, which in turn allowed authorities to stop cars coming onto the bridge.”
I was wondering about that. This video does a great job of showing that too. You can see the emergency lights from police or whatever blocking off and traffic being effectively halted. Yes, this is terrible, but it could have been so much worse on every possible scale.
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Until we get actual forensics in front of us I’d be hard pressed to carve in stone what a Maryland governor has stated. It did appear to be going fairly slow. I’m sure that someone has done the math based on the video footage already.
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They deployed their port anchor in an effort to slow down upon the power loss. I assume the 8kn were the initial speed rather than speed on impact. Probably taken from AIS data
ETA: the last recorded AIS speed data before impact is 6.8kn, down from 8.7kn before the deviation from course.
Yes, I subscribe to Marinetraffic, why do you ask?
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