Blog 131 - MV Dali Crashes Into Baltimore Bridge
- ranganathanblog
- Apr 22, 2024
- 14 min read
Reference can be made to the following site:
A few of you may have already read this article. I am publishing this now in my blog for continuity as well as for my Linkedin contacts, as I intend to follow it up with a sequel very soon.
The name MV Dali will be deeply embedded into the annals of Baltimore for all the wrong reasons.
The few moments before the collision caught on video is a very frank testimony to the problems that the vessel has been facing.
The ship’s lights go off a couple of minutes before the collision, come on a minute later and goes off almost immediately.
Puff of smoke between the two 'black outs' that occurred. Note the Navigation Light on the Christmas Tree - it remains on even after the 2nd black out, suggesting that the Emergency Generator was running.
It suggests that
When they had a black out they were running only one generator, which is not likely as, with pilots still on board, no Chief Engineer in his right mind will take one generator off load. Ipso facto, two would have been running.
Which means we have to assume that both generators were affected - for whatever reason - at the same time. If only one generator was affected, the second would have held, with the ‘Non-essentials’ having tripped off and the load reduced, unless the Bow Thruster was running. But, for the Bow Thruster, all 3 Generators would have been needed.
One can presume that the Bow Thruster had been switched off after leaving berth, as it becomes ineffective after the ship reaaches 4 knots speed. Hence, the 3rd Generator would have been switched off and kept on ‘Auto Standby’.
The lights coming on after a minute co-incides with ‘Stand by’ Generator (not Emergency Generator) settings, which starts, comes on load and almost immediately trips, which indicates no fuel was coming to this generator also, same as for the first two.
The Generators and the Main Engine would have been running on either Marine Diesel Oil (MDO) or Marine Gas Oil (MGO), as per US Emission regulations.
Analysis
What all are the reasons why a vessel can lose control?
Damaged rudder. It could have hit an object and been damaged. It could have been damaged and the stock twisted if the vessel had run aground in the stern area.
As far as the Dali is concerned, not relevant.
The Bridge Steering Control panel - control lost. Not really relevant, as the chances of losing all the controls at the same time - Manual ~~ Auto ~~ Follow Up ~~ Non Follow Up - is highly improbable, unless there is a power failure.
When the ship was alongside in Baltimore for more than 80 hours, a Port Worker had mentioned that there had been one, maybe two black outs, which were soon brought under control. It suggests that they had started using a recently bunkered MDO or MGO and they were able to control the situation by changing fiters.
When the first black out took place in proximity of the Bridge, irrespective of conditions, the Emergency Generator would have automatically started within 30 to 40 seconds, depending on the timer setting, and would have continued to run till somebody goes to the Emergency Generator Room and physically takes it off load and stops it.
If it did not start, it is likely that, when they had the black outs alongside in port, the selector switch on the Emergency Generator panel had been turned to ‘Manual’ and not kept on ‘Auto’. Hence the EG did not automatically start.
With the Emergency Generator running, the Emergency Switchboard comes automatically on line and is alive.
As per SOLAS, power to one Steering Gear motor is always supplied through the Emergency Switchboard - it could be the port motor or it could be the starboard motor.
On the Bridge, on the steering panel, there will be a placard as to which motor power is supplied through the Emergency Switchboard.
Normally, with pilot on board, the selector switch is kept on both motors, as a precaution.
With a power blackout and had the Emergency Generator automatically started, the selector switch could have been turned to the motor that is supplied through the Emergency Switchboard and one steering motor would have been available for steering.
Moving at around 7 knots, a hard over may have saved the vessel from crashing into the supports of the Bridge, unless they were too close. (There were 3+ minutes between the blackout and the crash).
Secondly, if the Bridge Steering had, for some reason, failed, the option would be to rush to the Steering Gear Room, engage the Emergency Manual Steering and, with one motor running, steer and receive helm orders, communicating with the Bridge through a dedicated ear and mouth piece, kept always connected and tested each week. This change over to manual takes about 20 seconds.
Seeing the location of the Bridge, it will take at least 2 minutes for a Bridge Officer to reach the Steering Gear Room aft and change over to Emergency Steering.
Meanwhile, in the Engine Room, with only 22 crew on board, I have to presume that only 3, maximum 4, people were in the Engine Room - the Chief Engineer, the Duty Engineer (maybe the Third Engineer, as it was past midnight) and the Electrical Officer. Maybe a Motorman.
Minutes before the ‘Black out’ ocurred, an alarm would have sounded. If my surmise is correct, the ‘auto filter’ for Generators alarm for ‘differential pressure high’ would have been indicated, the ER panels, screens and the printer would have recorded the time and nature of the alarm.
(To do a post analysis of any event, the best place to start would be the ‘Alarm Recorder’. The first alarm to go off is the culprit, followed by a whole set of alarms).
With the filter getting choked up fast, fuel input to the Generators drops sharply.
By the time an Engineer reaches the filter, Generator rpm would have dropped, frequency drops, voltage drops and, when the set point of either low frequency or low voltage is reached, the running generator automatically goes off the Main Switch Board.
Black out occurs all over the ship. Running machinery stops.
Each alarm gets recorded.
The Generators may or may not have stopped, depending on the quantity of fuel coming to the Generator. They may run oof-load on 250 to 300 rpm with the reduced input of fuel for a couple of minutes or, if no fuel at all is reaching the fuel pumps, may slowly come to a stop. Normal running rpm of the Generator is 600.
Emergency Generator should start automatically in about 30 seconds to supply lighting to Engine Room, Accommodation. Deck Lights are not connected to the Emergency Switchboard, except Lifeboat Decks, Embarkation ladders.
The now-live Emergency Switchboard, is now capable of supplying power for Bridge Equipment, Navigation Lights, one Steering Motor and, if motor driven, to the Emergency Fire Pump and Emergency Compressor.
Meanwhile, in the Engine Room, the third Generator, which would have been on ‘Auto Standby’, the Black Out would have triggered the start within 40 to 50 seconds, and comes on load. That is the time the few Deck Lights in the passageway under the containers would have come on. These lights, not impeding navigation, would have been kept on for deck staff to go to the Forward Mooring Stations
Even before the Engineers could have reached the Filters’ location to change over to the ‘Standby’ filter, the third Generator, lacking fuel, also stops.
A little later, a puff of smoke is seen from the funnel.
This is not the Emegency Generator starting as, by SOLAS, the Emergency Generator should be located away from the Engine Room in the event of an ER fire.
After a Generator is started, it takes at least a minute before the smoke reaches the top of the smoke stack in the funnel.
Irrespective of the efficiency of any Generator or Main Engine - or Auxiliary Boiler for that matter - a puff off black smoke can always be seen at first start, for a few seconds.
With all the auxilaries having tripped, there was really no hope of giving an ‘astern’ movement.
Could it have been a Main Switch Board failure and not a fuel related Generator failure?
If only a portion of the MSB was affected, that of one Generator, the second Generator would have held. Maximum, the ‘Non-Essentials’, such as Galley Power, Fridge and AC Systems, Accommodation and Deck Lighting, Ballast Pumps (if running) etc would have all tripped to ensure that the single generator does not get overloaded.
If the entire MSB was affected, the third generator would not have come ‘on load’ for even the minute that it came on.
After a Black Out, and a ’StandBy’ Generator starts and comes on load, the following happens:
All the ‘StandBy’ pumps essential for running the Main Engine, automatically start, as per the Auto Sequence set in the shiyard.
They start one by one, the full sequence taking about 40 seconds.
The Main Engine is then ready to start. The Fuel Setting Handle - either on the Bridge or the Engine Control Room - needs to be brought to the ‘Stop’ position and air applied, as in normal starts. In this situation - of a Black Out - the controls are normally taken down to the Engine Control Room.
On Fuels:
Main Engines used to run on 180 Centistokes HFO in the 70s and 380 cst in the 80s and 600 cst after the year 2000. 600 cst oil was akin to tar and would not flow easily. To pump the fuel from a double bottom, it had to be heated to at least 40+ deg C and about 60 deg C in winter.
Generators - in the 70s and before - used to run on MDO and, over the years, changed to blended oil, then to HFO - the same as was being used by the Main Engine.
Then came the question of sulphur content and, due to the insistence of Emission Controls, it dropped from 4% sulphur to 0.5% or thereabouts.
Then came the change to MDO or MGO when entering port. The problems started then.
Diesel fuel itself contains paraffins in addition to other hydrocarbon groups. However, diesel fuel contains also napthenics and aromatics, which are not so favorable for combustion.
Previously, with Generators on HFO at sea, as very little MDO or MGO was used, it used to lie in the Settling Tanks or Service Tanks for weeks together, giving a chance for the sediments to settle. (Evidence - DO Settling and Service Tanks used to have more sludge in the tanks than FO Settler and Service tanks, when opened in Dry Dock).
Over the years sediments and contaminants became more and more in MDO and MGO, which caused filters to choke more often.
Of Filters
Older ships had mesh filters with different micron capacity, easily exchangeable and cleanable with a solution of diesel oil and compressed air. Spare filter baskets were kept ready in minutes.
Fuel Oil filter construction and design changed slowly after the year 2000, to cope with dirtier and dirtier fuels.
Sintered porous candle type filters were introduced, made of different materials - mostly stainless steel. Even the smaller microns of contaminants were filtered.
Depending on the differential pressure gauge - one assumes that the gauge is in working condition - the ‘Self Cleaning’ or ‘Auto Clean’ filter is automatically cleaned, based on either a timer or when a set differential between the inlet and outlet pressure is reached. The more the contaminants, the more frequent the self-cleaning. A counter shows the number of self cleanings being done automatically. The Engine Room Log Book is supposed to show these counter readings noon to noon. Using this reading, an Engineer deduces that the filter’s automatic cleaning has ‘come on’ more often than the specified automatic timer setting for ‘back washing’ the filter and takes appropriate steps to rectify the problem.
The candle type sintered filters are not very easily cleaned, takes time. The ship carries about 3 sets of spares at the most.
Both, HFO and DO, contain paraffins, which is a wax like ingredient, in small quantities or large quantities, depending on where the oil is bunkered and its source.
Paraffins in the HFO, whether in large quantities or small, do not affect the sintered candle filters as, with Fuel Oil being heated to 130 to140 deg C, the paraffins melt, are liquidy and flow easily with the Heavy Fuel Oil to reach the Fuel Pumps and the Main Engine and Generators when at sea, as both are on HFO. In modern day ships, both - the Main Engine and the Generators - run on Heavy Fuel Oil at sea. So, the chances of choking of filters due to paraffins in the oil is small. On the other hand, solid contaminants will choke the filters fast, if allowed entry into the system.
Fuel Oil and Diesel Oil Purifiers of today are marvels of engineering, of physics and various other disciplines, meant to transform heavily contaminated fuels - solid conntaminants - into clean fuels. Water is also removed. The Purifiers, however, are not capable of removing paraffins in the oil.
The problem of the filters getting choked more often is compounded by the presence of paraffins in the Diesel or Gas Oil, as these oils are not heated to run generators or main engines.. Some of the oils have small quantities of paraffins, some large. But Diesel Oil analysis do not measure the quantity of paraffins, as Labs have not been asked to. The wax like paraffins quickly clog the pores of the filter. They are not easily cleaned away. Auto cleaning of the filters, based on increased differential pressures, is not sufficient to clean away paraffins. They have to be removed from place.
The only method of quickly cleaning them is to run a flame over the sintered candle to melt the paraffins.
I have had personal experience of this happening and, very soon, we ran out of clean filters. (There can be as many as 18 candles to a filter for the ME Fuel Filters and a smaller number for DG Fuel). Any number of changes of filters would not have mattered.
Luckily, we were able to perceive the root cause of the problem and straightaway changed the diesel oil to a previously bunkered oil, to restore a semblance of sanity. We were inches away from a blackout while navigating in close quarter situations, in a traffic separation scheme.
I suspect that the ‘Dali’ had similar problems and they kept changing filter candles, without realising that the fuel was the cause, most likely the paraffins in the diesel oil.
Could they have explored other alternatives in the couple of minutes they had or before they left port?
If it is true that they had a Black Out when alongside during cargo operations, they should have explored the reasons for failure with more caution. If necessary, they could have delayed the ship till a safe alternative was found.
It is always a wise precaution to have on board bunkers from two sources, whether HFO or MDO or MGO, so that - in the event of a problem with one fuel - you can empty out the Settler first by dropping it into the FO Leak tank, transferring oil from the alternate source, running it through the purifier, and filling up the Service tank after draining from the bottom to get rid of the bad fuel. This takes time, but is worth it, even if the ship is delayed. Most ships have only one DO Settler and Service tank.
It is a bold decision to take, but worth it.
Has the present shipping scenario contributed to this event?
Yes, definitely so. The profusion of bad quality fuels all over the world is the main factor. Ships have had to cope with bad fuels for a long time and it has to stop. The Ship Owner or Ship Manager or the Charterer is least bothered about what quality of fuel is being supplied to his ship, as each entity has shut himself out of the loop when ordering fuels of quality, as it costs higher to supply good quality fuels. This kind of accident was only waiting to happen.
In today’s world, most of the time it is the Charterer who places the order for fuels and chooses the port of supply. The person in charge of placing orders for fuel in the Chartering department is likely to be one of the most junior of their staff, with hardly any experience and, definitely, not a person who has had sailing time to his credit. He has been instructed by his bosses to look for the cheapest of options, damn the quality.
I have always noticed that when we bunker from BP or Esso or Shell and some of the more reputed companies, there is never a problem with the fuel. But when supplied from a non-conventional source, there always trouble.
The Pre-Bunker information about the quality of bunkers to be supplied, along with a reputed Lab Analysis Report, should be sent to the Vessel and its Managers. The Vessel’s Chief Engineer should have the right of declining to bunker, if the quality is poor, without fear of losing his job, without fear of being reprimanded.
The pre bunkering Lab Analysis should include content of paraffins and acid content in the fuel and DO to be bunkered.
Minimum Manning Certificates’ are, presently, very much in favour of the Ship Owner and the Ship Manager, so that he can cut his crewing costs. Many ships do not even carry Junior Engineers or Deck Cadets, so there is no continuity. Unless one learns as a junior, he will not be able perform as a senior.
Manouvering Operations of a ship comes under the clause of ‘Critical Operations’ that a ship is subjected to. By reducing the manning to a bare minimum, only skeleton staff are available during Critical Operations, leaving no ‘Factor of Safety’, no room for even the smallest of problems.
Imagine the chaos in the matter of mv Dali’s Engine Room. Who should go to attend to the Filters?
Who should attend to the flurry of alarms flooding the computers?
Who should attend to the desperte calls from the Bridge?
Who should man the Main Switch Board?
Is there any one to spare to run to the Steering Gear Room and await orders?
In the meantime, purifiers will be overflowing having tripped.
The Auxiliary Boiler would have tripped and needs to be reset.
All that is needed to complete the chaos is the Chief Cook ringing down to say that he does not have Galley Power - he is in the middle of cooking an interesting dish. “Can you switch on the Galley Power?”
As long as the mandatory “Minimum Manning Certificate” and “Minimum Rest Hours” continue to be in force, shipping is likely to see many more accidents, the former more than the latter.
“Minimum Manning Certificates” Hrrumph.
Who will bell the cat as far as bad fuel is concerned? I think the Charterer, who most of the time orders the fuel, has to take full responsibility for supply of bad or contaminated fuel.
With bad fuels being supplied, then no authority or organisation should complain about pollution from shipping. Or accidents, for that matter.
Conclusion
While paraffins can have a shut down effect on generators, another - and more dangerous - contaminant has found its way into the industry.
Mafia dealing in the disposal of industrial waste, such as waste acids, find it convenient to dispose off the waste acids into shore bunker tanks of Diesel Oil or Gas Oil. 10 cubic metres of acid being mixed with Ten Thouand cubic metres may seem innocuous.
But even a 0.001% of acid in diesel oil can waste away the finely polished - and nearly clearanceless - fuel pump barrel and plunger. Quickly, the fuel pumps lose their capacity to pump and the generator shuts down. Not knowing why the first generator stopped, a second is started, only to find the second generator’s fuel pumps waste away.
How do we find the acid content of diesel oil that is bunkered? Even laboratory analysis for acids is difficult. But it is possible to find out even before bunkering takes place.
When checking the ullage of the bunker barge, take a few drops of the diesel oil and place the drops at the back of your palm. The skin will burn if there is the smallest amount of acid. Refuse to bunker this oil. If possible, take a sample from the barge as evidence.
A sister ship of the one I was sailing on sank in mid Atlantic during rough seas with all hands on board, when they lost all three generators and could not start even one, according to their ‘May Day’ message. The ship was carrying heavy steel coils in the lower hold, the lashings gave way in the bad weather, the steel coils smashed through the side plating and the vessel sank. Being Chief Engineer of the sister ship, I was asked to give my opinion.
On the previous voyage, in one port in the US, I had refused to bunker diesel oil bcause of the ‘acid test’ (of a drop of the DO on to the back of the palm). The sister ship had also bunkered in the same port prior to her fateful voyage.
Rangan
(Written on 3rd April 2024)
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