[chbot] Electrical connections

[Mark Beckett]

The report is here.

https://www.ntsb.gov/investigations/Documents/Board%20Summary%20Contact%20of%20Containership%20Dali%20with%20Francis%20Scott%20Key%20Bridge.pdf

As always there are multiple things that contributed to the accident. 
Some of them are design and others are operator error.

A good management system should have shown the switches in Manual mode 
and the flushing pump active.


You may recall one of the ferries lost all propulsion some time ago. 
This was after a repair on one head on one engine was completed and it 
was not run to temperature afterwards.

The repair had pinched an O-ring and it after departure released steam, 
which the smoke detectors assumed was smoke. Luckily the Electrical 
Engineer override the standby generator that gave them some power and 
they could release the anchor.


What I found stranger was the engines shared a common water cooling 
system ie they weren't redundant ie a single point of failure.


It was rather surprising that this accident didn't recommend running the 
standby generator within confined waterways.

45 secs is a very long time, given that Airport generators are required 
to start and take load within 15 secs.

Airports run the standby generator during low visibilty to ensure the 
changeover is less than 15 secs during a power fail so they can avoid 
loosing landing lights.


Mark


On 21/11/2025 20:57, JR Borrett wrote:
> It would be interesting to know the chain of events in terms of how 
> failure of the control system was caused by one wire coming loose. One 
> would have to question a design that appears to have such a drastic 
> single point failure. No doubt there's a whole lot more to the story 
> but I couldn't find much on a quick search.
>
> Dick Borrett
>
> On 20/11/25 08:45, Volker Kuhlmann wrote:
>> What happens when a container ship's control systems fail
>>
>> https://static.dw.com/image/70594739_1004.webp [1]
>>
>> and the importance of doing a proper job with terminal blocks:
>>
>> NTSB Animation - Containership Dali Contact with Francis Scott Key 
>> Bridge
>> https://www.youtube.com/watch?v=bu7PJoxaMZg
>>
>> 1) 
>> https://www.dw.com/en/us-baltimore-bridge-collapse-caused-by-one-faulty-wire/a-74799287?maca=en-rss-en-all-1573-rdf
>>
>
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