Baltimore's Francis Scott Key Bridge Collapses after Ship Strike

[Nik_2213]

IIRC, a well-known Italian consortium has offered an 'Off the Shelf' design for a very nice cable-stayed suspension bridge. This would use the same approach roads etc, but safely span a lot more than the main channel. Nearest pier would be in shallow water, easy to protect beyond even unreasonable collision...

 

[Astronuc]

BALTIMORE (AP) — Researchers at Johns Hopkins University in Baltimore are assessing the country’s bridges to determine the likelihood of another disaster like the one that collapsed the Francis Scott Key Bridge.

The team includes students and faculty members and will focus on large bridges near major ports of entry, officials said in a news release Wednesday.

https://apnews.com/article/baltimore-bridge-collapse-johns-hopkins-4007c3b404f4b515cf4b4f9e2ba49da3

I would think it prudent to have essentially every civil/structural engineering university program in the country to be involved somehow, so that there is a population of students (future structural engineers), who will know be aware of bridge design and vulnerabilities. This somewhat akin to engineering students studying the accident at Three Mile Island, so that they would be aware of what can go wrong, and hopefully prevent future events.

 

[Rive]

hopefully prevent future events.

Honestly, I think most bridges are just not affected. As far as I'm aware river boats did not bloat up the same manner as seafaring ones. It's more of an adjustment/update of statistics than a really new situation.

 

[Nik_2213]

"What can go wrong..."

I still regret the demise of 'Engineering Failures' web-site, with those nape-prickling examples, very carefully documented and explained, of sundry infamous disasters.

IIRC...
Three Mile Island', beset by poor training and too many clamorous alarms to quickly identify the true problem.
An Asian shopping complex which had additional floors and heavy roof HVAC added above floors weakened by pillar-removal to create 'airy' retail environment.
The US hotel walk-way, its suspension system lethally compromised by unauthorised changes from plan.
Ronan Point modular apartment block, where a 'minor' gas explosion 'un-zipped' many panels' interlocks...
The 'DC 10' lesson, whose cargo hatch could show latched when it wasn't, and its loss' violent decompression warped aircraft floor, deranging congested control runs...

 

[Flyboy]

I would feel confident in stating that the majority of the most important safety lessons from engineering are written in blood. The above list has a notable exception in Three Mile Island, but the rest are painful reminders and lessons.

 

[OmCheeto]

too many clamorous alarms to quickly identify the true problem

As a former maritime electrical operator, I'd love to hear the story from the electricians point of view. And no holds barred on the finger pointing. I've thumbed through the NTSB report a couple of times, and in my opinion, it's a bit lacking in electrical details. I'm interested in the refrigerated containers. What was their cumulative load? Did they have to operate them in banks because their cumulative load was greater than the ship could handle? Were they in operation during the ships departure from the harbor? It was 1 am on March 26 in Maryland so I'm guessing it was not very warm out. (37°F per weatherunderground).

 

[gmax137]

I found this. Not sure if it is accurate.

The Dali is of the 10.000 TEU class, with 9.971 slots for 20feet containers (TEU) whereof 1400 slots can accomodate reefer containers.
In general, any containervessel can load a mix of 20feet and 40feet containers, as the container-fittings on the hatches and the container-guides in holds and on deck are designed for such purpose…

https://forum.gcaptain.com/t/mv-dali-container-counts/69007/14

 

[Borg]

Watched a cruise ship enter the harbor this morning - escorted by two tugs.

 

[Vanadium 50]

I'm interested in the refrigerated containers. What was their cumulative load?

So your suspicion is, ahem, Reefer Madness?

 

[Astronuc]

So your suspicion is, ahem, Reefer Madness?

Brilliant! Too much reefer, man.

 

[OmCheeto]

So your suspicion is, ahem, Reefer Madness?

It was mentioned here about a month before the report was issued.

Shortly after the bridge crash, I stumbled across a report that the electrical problems whle still in port were caused by power being supplied to too many refrigerated containers. The electrical load was re-distributed several time to stop tripping the circuit breakers.

I was not aware that refrigerated containers were electrically driven.

I also have not been able to find the report again, so please take the above with a bit of scepticism.

I found this news reference that mentions that theory

https://www.wcnc.com/article/news/n...apse/507-02e9a160-2ab6-463c-99ce-08f9862d9e45

I would like to see an official report, as jedishrfu's reference states;

The Dali experienced apparent electrical issues before leaving port, according to someone with knowledge of the situation. The person, who spoke on the condition of anonymity because they weren’t authorized to comment, said alarms went off on the ship’s refrigerated containers while it was still docked in Baltimore, likely indicating an inconsistent power supply.

Not quite enough information to form an educated guess, IMHO.

According to Gmax's reference in post #247, this class ship has a capacity for 1400 reefer containers. That's fine and dandy, but it doesn't tell me anything about the total load, or split partial loads, or surge currents if a bank of such reefers were being cycled on and off. Was the 30 man crew playing some kind of whack-a-mole game, plugging in and out 1400 extension cords to keep alarms from going off?

 

[Swamp Thing]

Speed running container ship...

 

[Astronuc]

Speed running container ship...

Ship at full throttle in harbor causes major South Carolina bridge to close until it passes safely
https://apnews.com/article/bridge-c...hrottle-ship-1bf6e945d5170314dfbfb1c761698217

A large cargo ship lost control of its engines and went nearly full throttle through a South Carolina harbor Wednesday, prompting the closure of one of the busiest bridges in the state.

Harbor pilots were able to help the nearly 1,000-foot (300-meter) ship, which was going nearly 20 mph (32 kmh), get under the Ravenel Bridge safely and eventually anchor several miles offshore while the Coast Guard investigates, said Randy Preston, commander of the U.S. Coast Guard’s Charleston Section.

 

[sophiecentaur]

Speed running container ship...

Why didn’t they just pull the valve lifter knob on the bulkhead? It worked for my Volvo twin 22hp without fail.
The equivalent could be built in surely as a manual override. I do realise the ship’s cylinders are bigger than my whole boat.

 

[gmax137]

Why didn’t they just pull the valve lifter knob on the bulkhead?

Maybe it's a two stroke?

 

[Flyboy]

Maybe it's a two stroke?

In all seriousness, it might actually be. But I think they still have a valve system that’s more complicated than the port-based ones you find on most small 2-stroke engines.

 

[gmax137]

In all seriousness, it might actually be. But I think they still have a valve system that’s more complicated than the port-based ones you find on most small 2-stroke engines.

Yeah even the two stroke engines have a fuel injection system. I'm not sure how marine engines are stopped, but I would guess there is a way to shut off the fuel.

 

[Vanadium 50]

Speed running container ship...

A little faster and it would give new meaning to the term "harbor pilot".

 

[Swamp Thing]

And a new meaning to "airship".

 

[sophiecentaur]

Yeah even the two stroke engines have a fuel injection system. I'm not sure how marine engines are stopped, but I would guess there is a way to shut off the fuel.

It makes you wonder about the qualifications of ships' engineers these days. The knowledge level of some may be restricted to 'operator' level and not 'fixit' level. Of course, there will be Engineers who really know their stuff but the accountants may not rate that s necessary.

 

[russ_watters]

Yeah even the two stroke engines have a fuel injection system. I'm not sure how marine engines are stopped, but I would guess there is a way to shut off the fuel.

Maybe they decided a fast but otherwise under control and powered ship was a lower risk than shutting off the engine and.....

 

[berkeman]

Maybe they decided a fast but otherwise under control and powered ship was a lower risk than shutting off the engine and.....

Yeah, the first thing I thought of was how closing that exhaust damper on the Dali killed the engine. Then I remembered that it resulted in a loss of steering...

 

[Vanadium 50]

Do we cut them a break for having made decisions that avoided an accident?

 

[russ_watters]

Do we cut them a break for having made decisions that avoided an accident?

Yes.

 

[berkeman]

Yeah, the first thing I thought of was how closing that exhaust damper on the Dali killed the engine. Then I remembered that it resulted in a loss of steering...

Do we cut them a break for having made decisions that avoided an accident?

Pilot Captain, I can stop the engine!

No.

 

[Nik_2213]

A similar argument to car throttle jamming open ?
Yes, you may turn off ignition, but you then lose the power steering etc...
Better to negotiate a few 'mild' bends, albeit scary-fast, and kill engine on 'straight'...

 

[berkeman]

Better to negotiate a few 'mild' bends, albeit scary-fast, and kill engine on 'straight'...

Better yet to click the transmission into Neutral and stop ASAP (safely).

 

[Nik_2213]

True !! FWIW, the example I half-remembered had the gearbox / shift jam, too...

 

[Vanadium 50]

Better yet to click the transmission into Neutral and stop ASAP (safely).

When you do that, the engine revs up instantly. It's pretty terrifying.

 

[berkeman]

When you do that, the engine revs up instantly. It's pretty terrifying.

Sure, but that's why engines have rev limiters.