Francis Scott Key Bridge Collapse

[rabler]

The graphic I saw suggested that the water depth at the support was only 20 feet, whereas the center channel is 50 feet. Not sure of the ship's draft but I'm guessing it may be resting in mud and just plowed a trough there. The ship isn't that old, I read that it was built or commissioned in 2015, and that their is suspicion that dirty fuel may have played a role in the power loss/engine failure. If so that throws some question back on the fuel provider, and given that it was bound for Singapore I wonder if it took on fuel in the U.S.

Even if there was a backup steering mechanism, the ship was being operated by two local harbor pilots. I can imagine, especially if there was a language barrier, that there could be significant issues in getting a backup steering mechanism working in the few minutes they had.

 

[Provincial]

The graphic I saw suggested that the water depth at the support was only 20 feet, whereas the center channel is 50 feet. Not sure of the ship's draft but I'm guessing it may be resting in mud and just plowed a trough there. The ship isn't that old, I read that it was built or commissioned in 2015, and that their is suspicion that dirty fuel may have played a role in the power loss/engine failure. If so that throws some question back on the fuel provider, and given that it was bound for Singapore I wonder if it took on fuel in the U.S.

Even if there was a backup steering mechanism, the ship was being operated by two local harbor pilots. I can imagine, especially if there was a language barrier, that there could be significant issues in getting a backup steering mechanism working in the few minutes they had.

I doubt a language barrier would be an issue. The ship was headed on a very obvious track, between the piers of the bridge. The Capitan could see where he was going, and that the ship was veering into the pier. The harbor pilots were there to make sure he was keeping the ship in the channel, and it was doing just fine until it lost power. Once the power was lost, the pilots were only along for the ride.

This is why there needs to be a backup steering system with a separate power source. That power source needs to be running anytime the ship is under weigh and not in the open sea. It should transfer automatically when main power is lost, just like a backup generator at a hospital. This is not rocket science, nor should it be expensive. Compared to the other costs of operating a ship this size, the cost would be negligible.

 

[woodchucker]

I doubt a language barrier would be an issue. The ship was headed on a very obvious track, between the piers of the bridge. The Capitan could see where he was going, and that the ship was veering into the pier. The harbor pilots were there to make sure he was keeping the ship in the channel, and it was doing just fine until it lost power. Once the power was lost, the pilots were only along for the ride.

This is why there needs to be a backup steering system with a separate power source. That power source needs to be running anytime the ship is under weigh and not in the open sea. It should transfer automatically when main power is lost, just like a backup generator at a hospital. This is not rocket science, nor should it be expensive. Compared to the other costs of operating a ship this size, the cost would be negligible.

I watched the analysis on the first page that someone posted. It was spot on, when the ship attempted to slow, they reversed engines and the ship sharply veered from it's coarse. They were better off not reversing, and just steering it through.. My opinion is the analysis was spot on.

edit: it was Dave @mmcmdl and its post 8 .. it's an excellent analysis, and makes more sense than some of the other armchair pilots.

 

[Ischgl99]

and that their is suspicion that dirty fuel may have played a role in the power loss/engine failure.

Dirty fuel is quite common, ship owners frequently buy the cheapest fuel they can find and sometimes the ships have trouble purifying it. When I worked for the centrifuge company, I got sent down to Houston to “teach” a chief engineer how to use the centrifuge because the owner believed he was discharging too much fuel while cleaning. The chief knew exactly what he was doing, the fuel was that bad.

There is a chief engineer that makes videos about his life as a mariner and has a video showing the centrifuges, if anyone is interested in that, I can search for it and post it.

I watched the analysis on the first page that someone posted. It was spot on, when the ship attempted to slow, they reversed engines and the ship sharply veered from it's coarse. They were better off not reversing, and just steering it through.. My opinion is the analysis was spot on.

Sal posted another update this morning, if you haven’t seen that, it has a lot of good information that goes into more detail. His analysis concludes the first time the power came back on, it was just the backup generator, the ships main power did not come back on until just before the collision.

 

[woodchucker]

if it's face book, I don't do FB, so please post a link.

 

[rabler]

According to an article in the Wall Street Journal, quoting Coast Guard Vice Admiral Peter Gautier, paraphrasing here about the Dali:
1.5 million gallons of fuel and lubricating oil onboard,
4700 cargo containers, of which 56 contain hazardous material but don't pose a threat to the public,
the bow is resting in mud, but there is no sign of flooding or damage on the ship.

The "or damage" comes from that quote, but it is pretty obvious from pictures that the ship took some damage from the bridge collapsing on it at the very least.

 

[Ischgl99]

 

[woodchucker]

I'm surprised that the purifier uses water.. I realize they don't mix, but just surprised. Don't really know how it works even after seeing it apart. where does the crud go? I assume the refined / cleaned oil goes to the outside as it makes it past those cones.

 

[rabler]

After watching that video, it appeared there were 4 identical "purifiers". @Ischgl99 do you know if they operating in parallel, or one per engine, or is it a redundant system with some complex control plumbing?

 

[matthewsx]

Marine engineering is an awesome field. If I could be a young man again I would give serious thought to enrolling in a maritime academy.

There is one in Traverse City near where I used to live and both our homes former owner and his son are graduates. The father may still be working as a boiler inspector on nuclear plants and the son worked a couple of seasons as a coal passer on the SS Badger (the last steamer on Lake Michigan).

As with most tragedies there were probably many factors that led to this one. Our NTSB investigators generally do a great job in analyzing accidents, but they take their time to understand all the factors involved.

John