Pretty much as soon as it happened people were tweeting about cyberattacks, distractions, etc.
BALTIMORE (AP) — It was the middle of the night when a dispatcher’s warning crackled over the radio: A massive cargo ship had lost its steering capabilities and was heading toward the Francis Scott Key Bridge.
Within about 90 seconds, police officers who happened to be nearby responded that they managed to stop vehicle traffic over the Baltimore bridge in both directions.
One parked sideways across the lanes and planned to drive onto the bridge to alert a construction crew once another officer arrived. But he did not get the chance. Powerless and laden with huge containers, the vessel smashed into a support pillar.
“The whole bridge just fell down,” a frantic officer said. “Start, start whoever, everybody ... the whole bridge just collapsed.”
There’s been a lot of this from the usual suspects.Along with saying that the crash only happened because "diversity hires" (i.e. non-white people) were in charge of the boat.... (I really wish I was making that up)
Ship was around 100 000 tons IIRC. Let's say it moves at the sluggish pace of 6,2 Km/h (that's a brisk walk), so 2 m/s.Saw this while catching up on bridge news last night. Didn't expect something like this to be in the bridge news. Watched the same video Kyriakos posted, and it's surprising just how quickly the bridge fell. Large cargo ships have a lot of inertia, but I hadn't realized just how much.
That sounds like a lot, although relating those numbers to something relatable is a bit challenging (note to self: kilograms, not kilotons of TNT, which is what I'm used to reading). I suppose a freight train is the real-world example that is most likely applicable. I've seen varying numbers, but the average ones I'm seeing is a freight train weights 15,000 to 20,000 tons, although some of the super-long multi-locomotive ones that are increasingly popular can weigh more. This also checks out with modern coal hoppers (still somewhat common around here, though a lot less so than 20 years ago) weighing over 110 tons each, as of 2012. Let's say the train moves at 38 mph (60 kmph), which may seem slow but these fully loaded trains aren't speed demons. That's 10 times the 6.2 kmph, but 1/6th to 1/5th the weight. So the train would be somewhere in the 166 to 200 kg of TNT range - or in other words, a bit more forceful than the Dali.Ship was around 100 000 tons IIRC. Let's say it moves at the sluggish pace of 6,2 Km/h (that's a brisk walk), so 2 m/s.
That's roughly 400 million joules, so about 100 Kg of TNT.
USA Today said:The 9-year-old container ship had passed previous inspections during its time at sea, but during one such inspection in June at the Port of San Antonio in Chile, officials discovered a deficiency with its "propulsion and auxiliary machinery (gauges, thermometers, etc)," according to the Tokyo MOU, an intergovernmental maritime authority in the Asia-Pacific region.
The report provided no other information about the deficiency except to note that it was not serious enough to remove the ship from service.
...
“The pilot was directing navigation of the ship as it happened,” he said. “He asked the captain to get the engines back online. They weren’t able to do that, so the pilot took all the action he could. He tried to steer, to keep the ship in the channel. He also dropped the ship’s anchor to slow the ship and guide the direction.
Don't think the anchor would be of any use. Even in a tiny static sailboat the anchor is of not much use if the bottom is sand, even a not particularly strong wind could be enough to move the anchored boat since the anchor won't grab at any point and will be easily dragged around. That happened in a beach near my hometown in Tarifa, at the southernmost end of the Iberian peninsula , years ago. A precious, about 45 feet sail boat owned by some rich foolish English tourists who obviously didn't read about Trafalgar battle, anchored in a beautiful cove to make night there. As it's usual in the zone, a fresh breeze blew from east all night, next morning she was on the rocks and the tourists had to be rescued by the police. She remained there for a number of years, in one piece and apparently in good shape, you needed to inspect the inners to find the rocks had left the hull totally bottomless and therefore was a total loss.That sounds like a lot, although relating those numbers to something relatable is a bit challenging (note to self: kilograms, not kilotons of TNT, which is what I'm used to reading). I suppose a freight train is the real-world example that is most likely applicable. I've seen varying numbers, but the average ones I'm seeing is a freight train weights 15,000 to 20,000 tons, although some of the super-long multi-locomotive ones that are increasingly popular can weigh more. This also checks out with modern coal hoppers (still somewhat common around here, though a lot less so than 20 years ago) weighing over 110 tons each, as of 2012. Let's say the train moves at 38 mph (60 kmph), which may seem slow but these fully loaded trains aren't speed demons. That's 10 times the 6.2 kmph, but 1/6th to 1/5th the weight. So the train would be somewhere in the 166 to 200 kg of TNT range - or in other words, a bit more forceful than the Dali.
Although, the train is also a lot longer, and flexible, so suspect it would have derailed and not had the entire force focus on one support pillar.
I've also seen that the Dali was traveling about 8 mph, with some sources saying it slowed to a bit over 6 mph before colliding (perhaps due to dropping anchor?). Which would multiply the 100 Kg figure by 1.6 at the 6 mph figure, for 160 Kg of TNT. Or about the same as a loaded freight train, but with all the force concentrated at one point.
Some updates from USA Today:
So the anchor was dropped prior to collision, and some "not serious enough" propulsion and auxiliary machinery issues were found last June. Could they have become more serious over the past nine months if not addressed?
Ship was around 100 000 tons IIRC. Let's say it moves at the sluggish pace of 6,2 Km/h (that's a brisk walk), so 2 m/s.
That's roughly 400 million joules, so about 100 Kg of TNT.
At 1:28:45 a.m.,[36][37][38] the ship struck a support column of the bridge, beneath its metal truss and at the south-west end of its largest span, at roughly 8 knots (15 km/h; 9.2 mph).[13] AIS data showed the ship traveling at a speed of 8.7 knots (16.1 km/h; 10.0 mph) at 1:25 a.m. before departing the channel and slowing to 6.8 knots (12.6 km/h; 7.8 mph) by the time of the collision two minutes later.[34][39]
Don't think the anchor would be of any use. Even in a tiny static sailboat the anchor is of not much use if the bottom is sand, even a not particularly strong wind could be enough to move the anchored boat since the anchor won't grab at any point and will be easily dragged around.
It will take 6 weeks or maybe months to remove the bridge and reopen the port of Baltimore.
If this was a wartime situation, how fast could the bridge wreckage actually be cleared?
Actually much more, because energy is proportional to the SQUARE of celerity. So 10 times the speed but 1/5th the weight means actually 20 times more energy, not double.That sounds like a lot, although relating those numbers to something relatable is a bit challenging (note to self: kilograms, not kilotons of TNT, which is what I'm used to reading). I suppose a freight train is the real-world example that is most likely applicable. I've seen varying numbers, but the average ones I'm seeing is a freight train weights 15,000 to 20,000 tons, although some of the super-long multi-locomotive ones that are increasingly popular can weigh more. This also checks out with modern coal hoppers (still somewhat common around here, though a lot less so than 20 years ago) weighing over 110 tons each, as of 2012. Let's say the train moves at 38 mph (60 kmph), which may seem slow but these fully loaded trains aren't speed demons. That's 10 times the 6.2 kmph, but 1/6th to 1/5th the weight. So the train would be somewhere in the 166 to 200 kg of TNT range - or in other words, a bit more forceful than the Dali.
So about twice the speed I took as baseline.Here you go
Francis Scott Key Bridge collapse - Wikipedia
en.wikipedia.org
True, i remember now the few lessons i took, they recommended to release a chain lenght three times the depth for the anchor to be horizontal. Later i have used only a tiny pneumatic launch with a simple grapnel which was of not use in sand. In any case the English tourists did something very worng obviously.Sand is an ideal holding bottom for your typical (modern) ship anchor; they're designed to dig in to it, the weight of an anchor itself (and the chain rode attached to it) doesn't do anything for ship holding itself but rather to make sure the anchor digs into the bottom. The catch in this particular case is that they don't dig in unless the pull/tension is closer to horizontal, and so Dali's merely dropping the anchor to the bottom wasn't going to do it, it needed to pay out some in order to get more horizontal pull and the longer it went without taking tension, the less time to actually stop Dali from hitting the bridge. It's one hell of a judgment call.