excellent point - understand
Hello all
As an ‘armchair sherlock’ with no experience on Bridge management or steering, I see a lot of comments from master mariners that makes sense.
In my opinion, from an engineering standpoint I offer the following.
At the moment of blackout (on hand steering) at 0125:00 possible the helm command was a couple or 3 degrees stbd. At 0125: 47 Helm reports vessel swinging to stbd.
Is it possible that when the EDG and ESG come on line (latest 0125:45), it first fulfils the initial command of 2 or 3 degrees stbd? Perhaps. Assuming the smaller pump did come on and the rudder moves to stbd first before moving to port, it is on the slow bell at 0.5 degrees/sec. So more like a minute to port 20. Meanwhile the vessel speed is dropping and rudder is losing its effectiveness. Wonder if the rudder did ever make it to hard port - if it did likely there was no load on the rudder (low vessel speed).
I wouldn’t be surprised if this smaller pump is used at sea speed when they are track mode to ensure rudder movements are minimal and gentle. But this also means that the pump may not be in spec condition. Per rules, this pump or power unit must be able to make 15-15 in 60 secs at half the vessel speed. Possibly not enough power to make had port or stbd at half design speed when the pump is new. They were making 10kts - about half speed.
PS: To 244 and Spo - for a minute I was wondering who RTM was - until it dawned on me! Hope you and the rest of the knowledgeable contributors such as Aus, KC, Tex. Hog, etc are doing well.
“If the ship was developing a bank cushion while steering a course the helmsmen would have been carrying rudder that the pilot should have noticed”
When navigating a narrow channel it is often necessary to be in a position where bank effect is present but negligible to a ship with engine running and prop flow over the rudder providing lift. When the engine stops and the flow turns to turbulence the ship control goes from 10/10 to 2/10 in an instant. In this case the ship was only slightly to the left but about to enter the area where the deep water opened up on the starboard side. The effect of the deeper water was not an issue for a pilot to correct until the ship actually began to enter that area. By then they had lost power.
this is something that I have never experienced - while I think I have a pretty good handle on the effect of ship speed vs engine speed on responsiveness to the rudder - having a bit of trouble wrapping my head around the “in an instant” part.
While this VDR transcript focuses on the BMT and pilots, the inaction (or incompetence) of the entire chain of owner (Grace), manager (Synergy) and crew cannot be understated.
The ‘cringe’ worthy patented turnbuckle design for arresting vibrations on the critical transformer is just one example.
Vessel crew placing the auto changeover of the transformer on manual. Departing on 2 DGs with the above known conditions. The list goes on.
BTW, the report indicates the vessel has a full VDR not the simplified S-VDR. The VDR is supposed to record rudder position. Word search - no mention of rudder or rudder position in the entire report. Maybe NTSB thinks it is just an appendage of not much significance.
Could be rate of turn monitor 
Glad to see your come back in style 
Confirmed. But still beats me why there are no mikes in the ECR for Gods sake. Can not believe all engineers are truth speaking dudes . Have different experience. Could be interesting to know what was said when all went dead. Mabe be the authors of this material were all engineers like in the case of MLC section of rest/work hrs .
Funny I realised there are no mikes in ECR on this forum after decades of sailing
Here my notes from fifferent sources regarding VDR . All, an average Joe navigator needs to know abt it .
VDR Operational requirements.pdf (483.1 KB)
It is not surprising that retired pilots are coming up with the best analysis of what when on. They are the ones who experience it day after day.
In an investigation such as this their expertise should be used as is the case in aviation investigations.
As a rider to my previous comment about the effectiveness of the anchor, a man would be a fool to hit the bridge with it still in the pipe regardless.
Boss, I don’t know how to break it to you, but if you read more than 3 threads on this forum it’s apparent almost everyone is talking out of their ass, my apologies for being transparent about it. Also to point out, this is an internet forum, an artifact of the old days of the internet and no more official or holy than a meeting of the minds at the local watering hole, and frankly I do not care if you are actually Barack Obama, I will continue to yap, as is tradition on this forum.
That being said.
Again, because this is just an internet forum, I apologize for not producing a Wikipedia article’s worth of content on the matter when I’m relaying information I have heard in passing.
I was referring to professional consulting Agencies like SEA LTD, or even those who have set up sole proprietor business such as Stephenson Maritime International. There are others but again, I’m not paid to be here, so I hope you are satisfied with these two example of professional Maritime consultants.
But please follow my logic with me in my contribution to this high value institution, forum.gcaptain.com:
When 244 said:
I brough up that if the NTSB is investigation something outside of their scope, hopefully, they have a contact with a reputable consulting agencies. Likewise, the UK’s MIAB would hopefully tap Trinity Houses’ Elder Brethren or the Honourable Company of Master Mariners if they didn’t have anyone with the experience in house either.
I’m sorry the NTSB didn’t call you back, but that does not mean they are relying on Chat GPT to conduct an investigation. At least hopefully, with the current administration you never know.
“having a bit of trouble wrapping my head around the “in an instant” part.”
Maybe it would help to picture an airplane wing with strong flow over the top and bottom of the wing and control surfaces. If the clean flow over the top and bottom of the wing turns to turbulence how long would it take for the situation to turn south?
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Listen - I have argued ship handling with a few Houston Pilots over the years and have lost every time ! So just to show how absolutely pig headed I can be - I hear you, and I know your experience says you are right. I just can’t get the idea of how, even disturbed water going past a rudder at 6 kts has no effect immediately.
I have been on a bunch of ships in narrow channels with limited UKC with a few knots of headway on and have gone all stop on the engine - never once did I ever see an immediate loss of steerageway.
I haven’t caught up on this whole thread but, the pilot almost certainly didn’t have power to the steering gear for a good portion right? The helm could have been reporting wheel and all the commands but it’s pretty likely he was trying to put on port wheel to maintain course but the rudder wasn’t working properly?
As for the anchor. I know in many ports they don’t want the stopper lifted for the transit in the event of an accidental release. And even if they got ~100 feet of chain out and tried to break it off…how would that react to the 100k ton ship going 7kts? I’m genuinely asking.. I don’t know how that would go.
One thing that does trouble me about the period between losing the main switch board supply and the EG connecting to the ESB is that the RAI’s would have been illuminated throughout via the 24V DC battery supply.
So, at all times, the bridge team could see the RAI’s. The helmsman was given a course to steer and therefore, in practice, would have been the only member monitoring the RAI’s.
Here is the fundamental question…..when the Pilot asked the helmsman to inform him if he lost steering….was the helmsman monitoring the illuminated RAI?
I agree with the point made by other members. The VDR recording of time stamped rudder order and response is fundamental to the completion of this transcript. That will clear up all supposition in this case.
Edit: We all know and understand the exact primary cause of this allision. We are now discussing secondary issues and there are many of them.
RAIs being backlit at all times (powered by the batteries and batteries charged from the ESB) and visible to all from anywhere on the bridge makes sense. So if the rudder is not position per order probably safe to say someone would have commented. Soon after the first blackout when the pilot asks if they had steering and the response being ‘yes’ might be because the Helm was steering 141, rudder was midships and no external force and therefor no need for any helm for the first few seconds after the blackout.
The first blackout was 0125 and at 0125:57.9 the note about power change over circuit is the main power being restored. About 58 secs. Corresponds to the port/Key Bridge video. At this point the main steering pumps I guess are also operational. At 0125:30 there is a note ‘change in alarm tone’. Possible this is the EDG coming on line – but no indication the emerg SG is switched on manually.
They have power for little over a minute until 0127:04. During this time, rudder order of port 20 is executed and stbd swing corrected.
Second blackout at 0127:04. Power restored at 0127:36. About 32 seconds of no steering. The video indicates a sharp swing stbd around this time (bank effect or water coming in from the channel?). Hard port helm ordered during the blackout and Helm confirms soon after power is restored. Rudder alone is not enough to correct course. No BT – has to be started from the BT panel on the bridge after blackout and main power is restored.
Possible the emerg SG and the BT not available as there were not started.
Power of compounding - bad luck in this case.
I have a great deal of respect for you and find your comments well articulated. I’m always pleased to see you comment because I know the discussion will be a good one and I often learn something new.
In this case I didn’t say the rudder has no effect immediately. I said that it goes from 10/10 to 2/10 immediately. In other words you go from 100% to 20% rudder power. On a ship where you were using 10 degrees rudder you are quickly using hard over rudder and getting much slower response. I have steered without engine power quite a bit… maybe once or twice a year for 30 years due to loss of engines, but sometimes almost daily just trying to hold up while another ship backs into a berth or maybe taking speed off for anchoring or berthing. It’s impossible to get a ship slow enough for berthing without stopping and drifting a bit. You just better be in a good position when you stop engines.
So, yes - there is steering (unless it’s a variable pitch prop, but that’s in another discussion).
Which brings us to the situation this ship was in. They were not in a good place to lose engines and I’m not sure they had the rudder all that time either. If you look at the chart and her track in the area where her problems began she was only slightly left of centerline. Not enough to be of concern in a normal transit, but being as little as half a beam width off is enough to smell the bank, as they say. Shortly after losing engines she entered a wider part of the channel as it opened out on her starboard side. The pull to the right increased.
If there was any swing to the right at all as she entered the wide spot that would increase the difficulty. It’s almost always easier to begin a turn than it is to check her up again.
I had hoped the example of the loss of laminar flow around an airplane wing would make things more clear. The power of a rudder comes from that wing effect.
Anyway… be safe iut there.
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The sad thing about this is that all these secondary issues under discussion , the very sad and unfortunate loss of 6 lives, the destruction of a bridge structure, 10 years of litigation, damage to a vessel, damage to the Baltimore/Maryland economy plus numerous other outcomes…..Is due to single point human error.
Low voltage feed changeover was on manual and not automatic. It is healthy to debate the secondary issues and lessons/improvements will evolve. We will learn.
At the end of the day…….this was always an accident waiting to happen. The timing and location is freakish. Why this did not happen in a vast, open ocean makes one reflect.
Sorry but have to pick you up on this.
Since 1988 the only Pilots Trinity House have authorised are North Sea Pilots so assuming an elder Brethren was 50 at the time then he would be 87 now so hardly current on modern ships.
The Honerable Company of Master Mariners is likewise hardly relevant either.
Some of my contemporaries held senior positions in the UKMPA , The UK Pilots union, and to my knowledge have never been consulted by the MAIB in investigating any incidents.
I do take on board what One Eighteen says about not hanging your fellow Pilots out to dry but in this instance input would be invaluable.
Trouble is that I said in the Mexican STS thread that 2 Pilots could not agree which way to sit on a toilet seat and sure enough here we are disagreeing on Rudder effectiveness in this case