I would have ordered full testing for the transformers, even though they’re saying there were no events that would indicate a problem with the transformer itself during the blackout. It’s easy to do and does not take more than half a day. The fact that the 87(differential function) tripped twice during energizing means that there is no restraint function on the protective relay or it’s settings were not correct. If the transformer is healthy those trips should not have happened.
I noticed quite a few non-standard terms used in the report. Whoever wrote it doesn’t sound familiar with this type of equipment. I wouldn’t expect them to be either. They should have involved a US based testing company. I’m not casting any doubt on HHI, but having HHI alone testing is a pretty clear conflict of interest IMHO.
Neither the preliminary report nor the new test report state what, if any, events were recorded on the protective relay for HR1 at 0125 at the time of the initial blackout. If nothing was recorded, other than breaker open, then that would point to the UVR.
The more I read through these reports, the more I’m starting to think NTSB is out of their depth in this type of testing. They really should have brought in an experienced, independent third party.
the bridge disaster would have been avoided if the transformer was not wrongly set to manual mode and two auxiliary engines were not wrongly fueled by flushing pumps
Not sure if that’s paywalled. But it describes the flushing pump, purpose, and location starting in section 56.
Basically the flushing pump is meant to flush the fuel lines when swapping from heavy fuel when entering an emissions control area (port). Not designed for normal continuous use, not automatic restart on blackout, not able to be started from the ECR. They ran it instead of the dedicated (and blackout-recoverable) generator fuel pumps to save time ($) according to the DOJ.
That explains why the actual generator breakers for 3&4 tripped after getting lights back on from the first blackout. They likely tripped on UV from being starved of fuel.
Seriously now, is this ship just a POS or did they hit something and put the prop out of balance? Bent shaft? One cylinder not firing? I would guess that vibration bad enough to be breaking transformer mounts is not normal.
PSMR* requires FMEA. Nowadays is called risk assessment. * means no loss of more than 50% propulsion power and retain steering capability under fire and flooding conditions. M/S Sigrid
IFP, integrated fire protection requires FMEA. M/S Sigrid.
Any hybrid built ship with lithium batteries requires FMEA.
Any low flash point fuelled ship requires risk assessment, fmea being part of it.
I just read the link to the District Court Claim and shook my head. It appears, on face value, to be damning.
“ 77. The DALI’s vibration issues were documented, well-known, and of concern to the crew. As explained in the introduction, the prior captain of the vessel noted “heavy vibration” in his handover notes on May 23, 2023, and he reported the same to Synergy:
78. Other crew records confirm that the ship’s excessive vibrations were causing numerous problems. For example, the chief officer reported in his handover notes that “constant vibration” was causing the cargo lashings above the engineering spaces to work loose:
79. On information and belief, Petitioners never reported their concerns about excessive vibration or their after-market modifications to the number 1 step-down transformer to manufacturer Hyundai Heavy Industries.
80. Excessive vibration can be detrimental to the proper functionality of electrical systems, including wire connections and transformers.
81. Before the DALI’s call in the Port of Baltimore, excessive vibration had loosened electrical connections in circuitry that was necessary to keep the circuit breakers for the number 1 step-down transformer from tripping.”
If indeed, this was the case, one would assume that both the Managers and Owners had a responsibility to issue the engineering crew with SOP’s regarding the setting of manual and automatic changeovers for the transformers not only whilst in Pilotage waters but also when under UMS operation.
If not, this absolutely beggars belief. The photo of the welded lashing turnbuckle does my head in. How did this vessel get through inspections?
This must make our resident forum engineers shake their collective heads.
Class dont do vibration analysis so the shipyard can design features that will vibrate to death and never get fixed just duct tape and chewing gum, or lots of welding.
I have a buddy ( MEng specialising in vibration and acoustics) ) that has had a lifetime career fixing vibration faults in ships and he says its a gift from god as he keeps going to the same shipyards solving the same problems over and over again.
A class of vessel I sailed in with twin 12 cylinder MAN main engines was well known for vibration except the one I was in . The two crankshafts were synchronized and we never had a problem. could there have been something amiss with the vibration damper fitted to the engine?
Michael,
One would also ask why both the transformers were not resiliently mounted……
I find it interesting that this legal team have presented some very specific and supposedly accurate information prior to the release of the NTSB final report. None of this was in the interim report.
Most likely the vibration was from normal cavitation and the 'tuning of the hull" so to speak.
I was on a ship that had been modified with a horizontal steel structure welded to the deck aft. Had to step over it to get aft.
It looked like it might have been a square cable conduit or some such but it was just to add strength to the deck in that area to dampen vibration. Even then that area shook more there than elsewhere.
Interesting info on the reports. Thanks to all for providing the links.
The civil suit docket is indicative of the clusterf*ck of a vessel operation.
Some of this is the consequence of regulations … case in point here is with the scrubber installation, the means to operate on HFO/MDO/MGO with mods to the original fuel system most likely designed by the management company without a whole lot of thought – objective being it’s fine as long as their submittal clears Class NK review.
Then there are shipyards and designers taking advantage of a old rule to design the emergency steering with about 1/5th the normal speed just so that they can limit the size of the emergency generator. Baltimore (or Maryland) should consider suing IMO (which includes USCG), HHI, the steering gear maker … all culpable in a way as the intent of rule was never meant to be applicable for the size of the ships today. I think the rule should be rescinded.
BTW, in both the reports no mention of the steering availability or rudder position after the emergency DG came on line. Possibly the emergency steering was also frozen/hyd locked.
I am a bit confused about the “synchronize the crankshaft” idea then. That is not really possible for humans to do.
I can synch engines by ear and I can hit the button on the synchronizer to do the same, but the only way I have ever seen that could synch the actual relative positions of the crankshaft and props is to use a synchrophaser. I can’t recall ever seeing a marine version of these, but they probably exist somewhere.
For the airplane version the simplest ones have a knob you turn for the least noise and vibration.
The only thing I knew about it is had something to do with the position of the crankshaft on each engine and it worked . How it worked was beyond my limited engineering knowledge as my previous experience with twin screw vessels was with AHTS vessels and before that steam turbines.
Sextantium I agree 100% with your comments. I’m not a marine engineer but have been chief engineer of three different power plants. I never, ever would have attempted to just “try closing it again” if a xfrmr (or gen) 87 differential rolled. I had that engrained in all my guys as well. Differential is a hard stop. And you then do electrical testing.
Agreed it possibly could have been magnetizing current restraint set too low, but why this time only? The breaker has operated 510 times before and they said there was no record of a prior 87 operation. I’d say that xfrmr has a very slight minor fault which is just on the edge of really flashing over. Most likely from the insulation abrasion from the vibration.
Also wtf would they restore power after the first loss to the same xfmr when they had the other one right there they could have closed in on?
Seeing that turnbuckle welded to the transformer if I was the master I would be changing my name and settling in a small Indian village that didn’t have a postcode.
According to the DOJ filing (linked in post #22) "heavy vibrations at certain speeds had been reported to the Synergy, the technical manager but this," the main engine “cannot be run between 65-68 RMP due to heavy vibration” just sounds like a description of the M/E’s critical rpm range.
The “constant vibrations” reported that was shaking loose the cargo lashing and damaging E/R equipment must have been from some other cause as the M/E typically passes through the critical RPM relatively quickly.
The vibrations may have been from the main engine but ships are not typically run continuously within the critical RPM range.
