Team-BHP > Road Safety
Register New Topics New Posts Top Thanked Team-BHP FAQ


Reply
  Search this Thread
39,836 views
Old 24th April 2024, 21:03   #91
Distinguished - BHPian
 
Join Date: Oct 2012
Location: Delhi
Posts: 8,108
Thanked: 50,928 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by kosjam View Post
I don't think it can be called "ascertained", more like it is assumed, basis the above mentioned article. Just because alarms were blaring on some refrigerated containers, doesn't automatically point out to power issues..
Within an hour of this accident happening there where videos on the Internet where you can clearly see the every single light on the entire ship going out, being resorted and going out permanently.

As a former chief engineer I can guarantee you that means you have a major problem on your power supply generation and power grid. If you see all the light on a commercial vessel going off, whilst underway, I would say there is 99,9999% chance it is having a major electrical power issue. If they remain out, it is most likely a total black out.

Here we see all lights going out and being restored quite quickly. That suggest some major load shedding and orr tripping of at least one of the generators. (They would have had multiple generators online). When the power is lost for the second time, all lights remain out permanently.

Irrespective, I agree we need to wait for the formal report on what actually happened and why. If I would have to take a bet, I would say they had a problem with synchronisation between generators. One of them dropped off line, the remaining ones should have been able to take over, maybe with some load shedding. They did pick up all load by the looks of it. If it had done any load shedding, some if not most of the deck lights would not have come back on, but the navigation lights would have.

It all took place in too short a space it appears for the emergency generator to kick in.

It will be very interesting to see what happened here.

Jeroen
Jeroen is online now   (3) Thanks
Old 24th April 2024, 21:14   #92
BHPian
 
Old_Salt's Avatar
 
Join Date: Mar 2017
Location: Delhi
Posts: 153
Thanked: 968 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by kosjam View Post
I don't think it can be called "ascertained", more like it is assumed, basis the above mentioned article. Just because alarms were blaring on some refrigerated containers, doesn't automatically point out to power issues.
There are a myriad of issues that could cause such problems, such as a local breaker tripping, switching off power to some containers to allow for loading/unloading and in general there could be a dozen other reasons for alarms to be blaring.

Now that the immediacy of the accident is gone, everybody is starting the blame game, and unfortunately, the blame will ultimately be passed onto the ship's crew, as it is generally the lowest factor in such cases, and the easiest to make a scapegoat out of.

Lets see what happens in this matter.
It’s not difficult to find out if a black out / preferential trip happened. Engine room Alarm logs are enough evidence. Crew interviews corroborated with the logs will be sufficient to “ascertain” this fact.
Old_Salt is offline   (1) Thanks
Old 24th April 2024, 21:18   #93
BHPian
 
Join Date: Jul 2021
Location: Mumbai
Posts: 316
Thanked: 1,600 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by Jeroen View Post
Within an hour of this accident happening there where videos on the Internet where you can clearly see the every single light on the entire ship going out, being resorted and going out permanently.

As a former chief engineer I can guarantee you that means you have a major problem on your power supply generation and power grid. If you see all the light on a commercial vessel going off, whilst underway, I would say there is 99,9999% chance it is having a major electrical power issue. If they remain out, it is most likely a total black out.

It all took place in too short a space it appears for the emergency generator to kick in.

It will be very interesting to see what happened here.

Jeroen

The article talks about power issues in port, which is based on alarms blaring on a few refrigerated containers. I am disputing this assumption. It is a possibility, but just one improbable one. More likely, the alarm could be temperature related, or one of many other possibilities, which was my statement in my earlier post.


It was definitely a blackout during the pilotage, and the standby generatiors kicked in. The fact that the standby generators conked off as well points to either a major earth fault, or more likely, clogged fuel filters, possibly the auto backflush filter.

Unless they had a longstanding earth fault in the system so massive that it managed to blackout the entire vessel without tripping individual supply groups, this issue seems to be a new problem which they faced for the first time at the wrong time.

Speaking from sailing experience as Chief Engineer in US waters doing these transits on an often daily basis.
kosjam is offline   (5) Thanks
Old 24th April 2024, 21:23   #94
Distinguished - BHPian
 
Thad E Ginathom's Avatar
 
Join Date: Jun 2007
Location: Chennai
Posts: 11,005
Thanked: 26,447 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

It looks like no attempt has yet been made to move the ship and/or remove wrecked bridge components.

Is this because of ongoing investigations, or simply practical considerations?
Thad E Ginathom is offline  
Old 24th April 2024, 21:26   #95
Distinguished - BHPian
 
Join Date: Oct 2012
Location: Delhi
Posts: 8,108
Thanked: 50,928 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by kosjam View Post
The article talks about power issues in port, which is based on alarms blaring on a few refrigerated containers. I am disputing this assumption. It is a possibility, but just one improbable one. More likely, the alarm could be temperature related, or one of many other possibilities, which was my statement in my earlier post.


It was definitely a blackout during the pilotage, and the standby generatiors kicked in. The fact that the standby generators conked off as well points to either a major earth fault, or more likely, clogged fuel filters, possibly the auto backflush filter.

Unless they had a longstanding earth fault in the system so massive that it managed to blackout the entire vessel without tripping individual supply groups, this issue seems to be a new problem which they faced for the first time at the wrong time.

Speaking from sailing experience as Chief Engineer in US waters doing these transits on an often daily basis.
Ah, correct! I had not realised those problem with the refrigerated containers was in port. You are correct, could be a whole host of reason for those alarms going off.

Are we sure their back up generator did kick in? There wasn’t all that much time between the first and the second black out it seems? Also, why would all the lights on deck come back on when on emergency power? Thats why I thought about sync problems between different generators and subsequently everything tripping.

Jeroen
Jeroen is online now   (1) Thanks
Old 24th April 2024, 21:33   #96
BHPian
 
Old_Salt's Avatar
 
Join Date: Mar 2017
Location: Delhi
Posts: 153
Thanked: 968 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by Thad E Ginathom View Post
It looks like no attempt has yet been made to move the ship and/or remove wrecked bridge components.

Is this because of ongoing investigations, or simply practical considerations?
This article sheds some light on your query. Investigations will be carried out concurrently, however making the channel operational is the top priority.

https://www.cnbc.com/2024/04/08/dali...reopening.html
Old_Salt is offline   (1) Thanks
Old 24th April 2024, 21:38   #97
BHPian
 
Join Date: Jul 2021
Location: Mumbai
Posts: 316
Thanked: 1,600 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by Jeroen View Post
Ah, correct! I had not realised those problem with the refrigerated containers was in port. You are correct, could be a whole host of reason for those alarms going off.

Are we sure their back up generator did kick in? There wasn’t all that much time between the first and the second black out it seems? Also, why would all the lights on deck come back on when on emergency power? Thats why I thought about sync problems between different generators and subsequently everything tripping.

Jeroen

The general rule for electrical power on board is that an emergency generator must be capable of starting and coming on load within 45 seconds of a blackout. The standby generators generally start and come on load within 22-25 seconds. So in my analysis of the crash video, the sequence of events was:

1. Initial black out due to fuel issues (sudden starvation of both generators due to common fuel filter choking)
2. Standby generator of equal capacity kicking in, evidenced by the lights coming on the first time.
3. A second blackout due to the same fuel filter issue plaguing the standby generator as well
4. The lights returning due to emergency generator coming on load.
kosjam is offline   (3) Thanks
Old 24th April 2024, 21:54   #98
BHPian
 
Join Date: May 2023
Location: Riyadh
Posts: 357
Thanked: 2,228 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by Thad E Ginathom View Post
It looks like no attempt has yet been made to move the ship and/or remove wrecked bridge components.

Is this because of ongoing investigations, or simply practical considerations?
They are moving that wrecked bridge and the damaged containers are also being removed from the ship, progress is slow and tedious as expected. Heavy jaw cranes have been put up at place.

These damaged steel structures are pretty heavy, today only they have moved one 500 tonne structure.

You can see the progress live on YT, they are streaming it 24hrs.


https://www.youtube.com/live/2sv7SA2...oP80YyvJg_tWX_

Last edited by NomadSK : 24th April 2024 at 22:01.
NomadSK is online now   (2) Thanks
Old 25th April 2024, 15:50   #99
Distinguished - BHPian
 
Thad E Ginathom's Avatar
 
Join Date: Jun 2007
Location: Chennai
Posts: 11,005
Thanked: 26,447 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by NomadSK View Post
You can see the progress live on YT, they are streaming it 24hrs.

https://www.Youtube.com/live/2sv7SA2...oP80YyvJg_tWX_
Thank you very much. As is the nature of the internet, that led to other interesting stuff, such as this youtube...

Thad E Ginathom is offline   (2) Thanks
Old 25th April 2024, 16:04   #100
BHPian
 
Join Date: May 2023
Location: Riyadh
Posts: 357
Thanked: 2,228 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by Thad E Ginathom View Post
As is the nature of the internet, that led to other interesting stuff, such as this Youtube
True, thanks to the internet knowledge is freely accessible, unlike before.

I had been following this guy for the updates and also this guy below, see which one makes more sense or makes it more entertaining


Last edited by NomadSK : 25th April 2024 at 16:07.
NomadSK is online now   (2) Thanks
Old 25th April 2024, 17:58   #101
BHPian
 
Join Date: Mar 2024
Location: At Sea......
Posts: 102
Thanked: 207 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by kosjam View Post
So in my analysis of the crash video, the sequence of events was:
1. Initial black out due to fuel issues (sudden starvation of both generators due to common fuel filter choking)
2. Standby generator of equal capacity kicking in, evidenced by the lights coming on the first time.
3. A second blackout due to the same fuel filter issue plaguing the standby generator as well
4. The lights returning due to emergency generator coming on load.
In all probability above scenario is what is most likely to have occurred.

However, what is interesting to know is that the generators must have been operational throughout the port stay running on the same fuel and also during the initial phase of the outbound transit from the berth, so how come the sudden failure?

Did they change over the generators & fuel source during transit (unlikely)?

For those not familiar with visiting USA ports, compliance with CFR is mandatory and the USCG ensures the same. Following is an extract from 33CFR Reg 164.25:

Name:  33 CFR.PNG
Views: 38
Size:  88.6 KB

Item No.3 above is very specific, so if it was indeed checked wonder what else could have gone wrong?

Last edited by BlackBeard : 25th April 2024 at 18:00.
BlackBeard is online now   (1) Thanks
Old 25th April 2024, 19:27   #102
BHPian
 
Join Date: Jul 2021
Location: Mumbai
Posts: 316
Thanked: 1,600 Times
Re: USA: Baltimore bridge collapses after cargo ship crashes into it

Quote:
Originally Posted by BlackBeard View Post
In all probability above scenario is what is most likely to have occurred.

However, what is interesting to know is that the generators must have been operational throughout the port stay running on the same fuel and also during the initial phase of the outbound transit from the berth, so how come the sudden failure?

Did they change over the generators & fuel source during transit (unlikely)?

For those not familiar with visiting USA ports, compliance with CFR is mandatory and the USCG ensures the same. Following is an extract from 33CFR Reg 164.25:

Attachment 2599017

Item No.3 above is very specific, so if it was indeed checked wonder what else could have gone wrong?

Fuel systems are very dynamic in nature. Tanks are huge, and sometimes sludge which might have accumulated in a storage tank could get sucked into the fuel systems, causing the auto filters to clog up suddenly. A change in storage tanks under consumption is another possibility.

Regarding generators being operational throughout port stay, as I mentioned above, fuel is a dynamic component. Secondly, there is a possibility that the generators were not running in ports, and the vessel might have been drawing power from shore facilities. (I am not on container ships, so would not be able to give specifics on this.)

Filters are generally built to manage a certain degree of sudden sludge influx, but there have been multiple instances of excessive sludge overwhelming systems.

Regarding the standby and emergency generators, they are tested, all parameters confirmed normal, and are stopped and put back on standby. They do not continuously run.

It could really be a really bad case of SHIT HAPPENS. If this is really what did happen, then it was their supreme bad luck, to say the least.

Hope that clarifies things.

Last edited by kosjam : 25th April 2024 at 19:28. Reason: error correction post proof reading
kosjam is offline   (1) Thanks
Reply

Most Viewed


Copyright ©2000 - 2024, Team-BHP.com
Proudly powered by E2E Networks