Thank you, Captain. For me, being on the lifelong curve of professional development as a shipbuilding, offshore operations and engineering management professional with 25 years experience behind my belt, you still have managed to show me some pretty much useful information.
Congradulation for your explanations examining every possible cause of the accident. I'm not a captain but a mechanical engineer and I appreciated you explaining the hydrodynamic forces to the propeller causing the ship to turn starboard.
Thank you sir. Thats the best explanation of this incident that I've read so far. I'm ex Navy. (Gunners Mate) I learned basic seamanship and worked on hydraulic and hydro-electric motors. The steering explanation was spot on and brought me back memories of changing those heavy motors out and refilling hydraulic fluid. New subscriber.
I had single screw ship experience in the navy and his analysis is spot on. Had the ship not backed down until it cleared the bridge, it would not have hit the bridge. At its distance to the bridge at time of failure, and the distance a ship will stop when going 8 knots, backing only compounded the problem. Just my opinion after years at sea on naval ships.
Based on the video that's now universally available of the failure and collision, the ship essentially lost power at the absolutely worst possible time to lose power. Even had she not gone back full, a collision was likely, as bank effects are present also from the piers themselves, as well as the dolphins nearby. But, excellent situational awareness allowed the pilot to call on the radio of a potential collision, preventing an even greater loss of life. That class of vessel turns on a really, really, really large dime. Having driven on that bridge quite a few times in military convoys, they got traffic shut down just barely in time!
Thank you for such a detailed and accurate description of what may or may not have happened from someone who clearly knows what actually happens on ships of this type. It certainly debunks some of the other theories from so called experts.
A good set of examples. You and I are in agreement. I have been telling people from day one that ship was not steered into the bridge, that the black smoke is most likely caused by the ship being placed full astern, which would cause the vessel bow to turn to starboard. This was an accident. The primary reason that the bridge went down is that the bridge protection system was/is totally inadequate. The bridge's protection system consisted of four, too few and too small, dolphins, two on either side of the bridge, and a wooden & steel fendering system around the bridge support legs. This protection system was designed to protect the bridge from much smaller, much lower hulled, ships than those of today. The government's neglect in updating the bridge protection system is mostly to blame for the loss of the bridge. Those who disagree, that the government is mostly to blame, I would like to you consider. Ships must travel on water. They cannot go around. Vehicles and trains operate on land. When they decide to build a bridge they must make allowance for the types of vessels that will continue to use the waterway. This bridge has been hit in the past and the risk of it being hit again will always be there.
Absolutely, they stuck the bridge in the way of established marine traffic from a major port. Maryland State and Governor should immediately foot the bill for protecting or replacing the other vital Chesapeake bridges or they have no business blaming the ship for the scale of the disaster and running off whining to Joe Biden.
That was exactly my thinking when I saw the sudden turn of the Dali and the smoke rising from the funnel. So I see it confirmed by a way more knowledgeable person now. Thanks you!
What a well explained video! I'm excited to watch more! I also had trouble with how fast you speak although your English is easy to understand. I'm not in maritime or an engineer and yet you made this complex topic easy to understand- thank you for all the extra graphics and showing actual engines! You remind me of Mentor Pilot. Wishing you much success!
Hi @Mustapha could I suggest speaking slightly slower or else adjusting the video setting so that playback is at 80 or 90% of your actual speaking rate. I have an add-on to my browser that lets me do that at my end, but most people are stuck with UA-cam's primitive Normal 75%, 50%, Normal, 125%, 150%. And most people won't even think to adjust the speed. I'm a native English speaker, I work in IT in Toronto, I've worked with people with lots of accents. Your English is fine, just a little too fast. I think slowing the playback speed slightly will help boost your viewer numbers. Anyway, great video, keep up the good work !
Being an impatient person, and one who also has been exposed to many non-native English speakers, I actually sped up the video to 1.5 speed. I usually listen to news and informative videos at 2X speed but because of the unfamiliar accent, 2X was a bit too fast for my ears. Captain, keep up the good work!
Good job Captain. A lot explained in a short time. All other “Baltimore” experts would have split this video into 10 parts to earn more revenue. It will be useful to further elaborate on the 3 most probable causes with additional scientific back-up. It will help NTSB to temper their findings to non-biased outcomes.
Thank you sir for taking the time to explain, very informative...sometimes it feels like our media is lacking on purpose to create and facilitate conspiracy with their lack of logical detail. Thank you.
Very well explained… thank-you. I learned a lot - when you explained the unbalanced forces on the shaft due to the water pressure … click! Seems a very plausible explanation. Now we wait for the NTSB report.
Thank you very much captain!!! Very detailed video. I've seen similar theory from a different captain, but without such detailed explanation. Based on this logic it seemed most probable case. There are so many details that are very evident for the professionals that are supporting this logic and this theory. The another captain also pointed that a speed of the vessel had dropped to five mile an hour or so, before collision. That is also supports this theory. Just recently, another ship lost it propulsion at New York port, but everything worked out safely.
@@MustaphaZehhaf It's a little bit of a complaint because I have difficulty understanding your accent. Though I was pleased to get the information, so I slowed it down to understand it.
Very correct demonstration ;) But I wonder why they would have reversed the engine since the vessel was correctly in the channel? This action, if verified, causes the accident.
In your theory you forgot the time needed to restart the main engine. First of all they had to restart cooling water,fuel pumps,lubrication pumps,etc. With a speed of 7 to 8 knots the motion of the ship through the water would still turn the propeller around and it would be difficult to stop it so that the engine could go astern. Besides ships that size would have a blockage to prevent the engine to be turned astern if the speed through the water is too high. This can be manually overridden but by doing so you risk breaking the engine down. Besides so close to the bridge it would be too little too late. I noticed in your clip you showed pictures from a LNG tanker of the Moss - Rosenberg type. That would have a steam turbine that would be even more difficult to turn astern without breaking it if the ship is doing the mention speed through the water. Let’s assume they managed to get the main engine up and running again. The logic thing to do would be to give a kick ahead so that you could steer clear of the bridge. At this time the heads of both those in the engine room and on the bridge were probably boiling due to the situation and the noise from all the audible alarms. The smoke that you see is probably from the auxiliary engines being restarted.
Any ship can go astern while still sailing ahead. It is mandatory and tested at the sea trial. So I don’t understand why everybody is talking about this thing about the propeller still turning ahead would prevent to go astern. Also I am a combined chief engineer and I can tell you that steam turbines react faster and better in those situation. We never break the engine when going ahead then astern. This is something we do regularly during manœuvrons in port anyway.
@@captcarlos it must have been five very long minutes. You know what will happen but there is little or nothing you can do about it. Thankfully the people on the ship’s bridge managed to send a message ashore so that they could stop all traffic and thanks to the police that reacted quickly and prevented even more casualties.
@@gaetansimard1594 With a small boat you can do that but not with a large ship engine. Yes , they test the engines astern on the sea trial but not at 8 knots ahead. On a large ship each cylinder might have a bore of 80 centimeter and a piston stroke of 2 meters. If you also add the fact that these engines also have 6 or more cylinders it is understandable large things we are talking about. Steam engines are stronger than diesel engines but they are also more delicate and must be handled thereafter. I have been a seaman for more than forty years, the last 23 of them as master, so I know a thing or two about handling large ships. My experience is both steam and diesel powered engines. If I tried to go astern when the ship was doing 8 knots I would probably break the engine and give the chief engineer a heart attack. Besides when you go astern with a large vessel you basically have no steering at all. What could save the situation is to give the engine a kick ahead to gain control of the heading but in this case I find it unlikely that they could manage to get the main engine available in the short time they had at their disposal. The first thing they would have to do is start an auxiliary engine and then synchronize it and connect it to the switchboard. This could be the reason why they had the second blackout. Then they would have to all the auxiliary systems to the main engine running before they could attempt to start it. A normal procedure is also to blow through the engine with starting air before attempting to start it but in this case it was a do or die situation,so they would have cancelled that. Starting air could have stopped the propeller from spinning long enough to attempt a start but it would be very risky. Even though they were sitting in a modern control room where most things in the engine could be operated remotely it still would take some time. An interesting question is if any breakers tripped. I am pretty sure that all of the fact will be revealed when the official report is published.
Do you mean if the vessel is sailing at full speed and encounters an emergency, she needs to slow down and stop then reverse? Of course NO, in case of emergency, the engine is there for these cases.
I agree with your reasoning. Further evidence supporting the full astern hypothesis is that ship heading didn't change at all for the full minute the ship was blacked out, and then it started to turn starboard right after some lights came back on and then the black smoke started coming from the stack. But a couple questions: - Is it plausible that the main engine was restarted in just 1 minute? One Chief Engineer on UA-cam thinks not. - Could the current from the Curtis Bay side channel have turned the ship?
Yes you can start a warm main engine within seconds if you get the auxiliary running (LO pump and fuel module unit) cooling water pumps is sometimes needed but not always. If the main engine overheat you have warning the shut-down. But it can take a few minutes before reaching shut-down at slow speed.
@@gaetansimard1594it's much harder to start the engine in reverse when the ship is moving forward though. The water on the propeller tries to push the engine to run forwards. It would be quite easy to start running forwards, but hard to start running in reverse.
@gaetansimard1594 the engineer also gave a time line to restart and believes the shutdown was fuel related which is why the 3 engines (2 generators and main) shutdown and the backup didn't come online. He also believes that according to the visual time-line that the black smoke was from one of the main generators
Nice video. I like the examination of different forces /causes /scenarios side-by-side. It would be interesting to know if the command was ever issued to go full astern, or if that is even possible in a tight timeframe. Would an observer see churning of the water under such conditions Another piece of information that would be interesting , would be the captains view of the harbor at night: how does he see the waterway, the obstacles , navigation markings/lights & charts wrt things to avoid, geographic points of interest, etc. as he makes his way out of the harbor
@@MustaphaZehhaf in particular: Not so much what was visible, but what could not be determined -- warning buoys, pier markings, boundaries of the channel, etc. I know the center channel light on the bridge looks pretty obvious. But what else gave them warning that they were dangerously close to the pier of the bridge. Were there markings on the high tension lines just before the bridge, etc, etc.
Not to be hypercritical but its hypothesis. Not hypnosis. He offered a hypothesis on the hypotenuse angle of the ship’s travel, he didn’t hypnotize or alter your state of mind.
I agree. The deep black smoke is main engine full astern, and the captain "prop-walked" his ship into the bridge. Single prop aircraft do the same thing.
obiously u are correct.pitch propeller with engine MAN,rapid swing to stb mean power ME back ,huge smoke as result od full astern.surprice no any usa institution until now present such significant move.
I would agree about the prop thrust..however a marine engineer (who actively works similar ships) stated that with the resets needed that by the time the generator was started there wasn't time to restart the engine. Everything else you state aligns with what you stated.
I am a combine chief engineer (steam and diesel) 30 years experience. I also think they that they started the main engine full astern, this is the black smoke, and that cause the ship to turn to starboard. Also think that it was not the emergency generator that kik in but one of the main. You need the main generator to start the main engine on a slow speed engine. You need the LO pump and the some aux equipment that are not supply by the emergency generator. But how they got the ship to blackout is still a mistery. Normally they should have two generators on the board during Stby and run on MDO. Probably a humain error.
This video just turned up in my suggested videos and at the start you suggested watching the previous video first and I did. Since this incident happened I've become more interested in how these large ships navigate. I've been picking up bits and pieces from various videos. I found yours more of an in depth explanation of the various things in play. I hadn't heard that the emergency generator is required to come on in 45 seconds. I had known that a rudder needs water flowing past it to have much effect so when the large propeller stops it blocks much of the flow. From the timeline in some other videos, the Dali appeared to start turning to starboard before power was lost or they had the timeline wrong for when power was lost. How much forward speed would a ship that size need for the rudder to be effective and how effective could it be with the propeller stopped? If they did reverse the engine, how much distance would be covered before the ship slowed significantly? Wouldn't the pilots and captain know that reversing the engine would cause the rudder to be ineffective? I've subscribed to see more and I will watch some of your other videos.
the Dali has a direct shaft to prop drive. It takes time to start the engine in reverse and ramp up power -- more time than they had. It also causes cavitation which reduces prop effectiveness. The proper course of action would be to increase speed ahead which counterintuitively would swing the bow to port.
I really wish the NTSB would announce the results of its tests on Dali's fuel so that other ships that had bunkered in some of the same ports as Dali would know if they can rely on the fuel in their tanks. It seems insane to me that ships are running around out there unsure if their fuel is contaminated.
I've never piloted ships but I've piloted cruising sailboats for decades thus I'm well aware of transverse thrust (aka prop walk) so, while recognizing there may be some large ship dynamic I'm unaware of, when I saw the stern swing to port and the black smoke I immediately thought of prop walk. I then checked to see if Dali was single screw and discovered she is, hence transverse thrust causing the turn remained my suspicion. Your analysis as a ship captain who would know of any big ship dynamics I'm not familiar with is most interesting. What I really can't understand is, if rudder control was lost, why the pilot or captain didn't employ the ship's momentum to clear the bridge.
This has puzzled me from the very early days after the accident. If it is known that reversing the propeller will cause both the stern to swing from line of travel and for the rudder to become irrelevant, why would anyone who knew what they were doing reverse the propeller due to a loss of power on the approach to a bridge? The ship was clearly not a danger to hit the bridge until the turn, so why command a reversal of the prop which is known to cause a turn which can't be countered by the rudder? I've played with boats for a long time and know for certain that a loss of power means the boat will continue in a straight line and clearly the pilot and master were aware of this as well, so why did they reverse the propeller? It just doesn't make sense unless they were completely incompetent or desired to hit the bridge.
Very good explanation Captain -Totally agree with your event and ship movement factual analysis based on correct theory, but in relation to the law the USA do not apply the LLMC convention version - they apply a US Version of shipping limitation liability which is similar in concept but not the same ( differs in calculation value unit, and slightly differs in what it covers). By the way good see another Moss-Rosberg LNG ship - I served on a 4 dome and 5 dome versions.
Of course the Captain is entirely responsible and will be held accountable. The Captain is the leader and if in ANYWAY a lack of his leadership, in any facet, caused the accident it is his responsibility. Misplaced faith in CHENG's leadership, CHENG's faith in an engineer, a trainee turning a wrong valve, somebody not doing their job or falsifying a report. It's all the Captains responsibility.
Here's my theory. Using the Marine Traffic AIS course track it's clear that there were two course changes. The first one occurs at the initial loss of power and consists of about an 8 deg overall slow veering turn to starboard. This turn initiates while the Dali is passing to starboard the open entrance of the Curtis Bay channel. The veering could plausibly have been the result of the last commanded rudder correction before the first power outage. In using the term veering I am implying that this first turn was a slow and continuous clockwise (from above) rotational movement pivoting on the ships CG. This seems to be indicated by the AIS course direction updates (gradual heading changes to starboard over the distance to the second course change). The second course change occurs just shortly after the anchor is released. This second turn occurs much quicker and over a very short distance when compared to the first veering turn. It was approximately 9-10 deg. The total course change to impact was from 140 to 159 more or less. I posit that while the release of the anchor would have almost no effect on reducing the speed of the ship it may have generated enough resisting force by contact with the bottom to accelerate the small clockwise veering moment that the Dali was already experiencing. In other words the Dali was suddenly, by the drag of her anchor, tripping over her toe. Keep in mind that the anchor chain drops out of the hull closer to the midline than to the sheer line and it's plausible that the anchor quickly got under the hull into a favorable position on the starboard side of the midline, increasing, through drag and leverage advantage, the clockwise moment. I do not believe the second course change was caused by propellor walk nor do I believe that the main propulsion engine was ever successfully restarted. I do recognize that arriving at those conclusions is plausibly constructible from the video evidence but I find as a theory it lacks persuasive support from chief engineers.
Is it important for the bank effect that a side channel was opening to ship starboard (rather abruptly) just before the bridge, seemingly where she did turn ?
@@MustaphaZehhaf so if the bank effect fades, allowing the stern to come to port, combined with a possible flow from the incoming channel, also pushing the stern to port, combined with the reverse engine and the propellors effect, turning the ships bow to starboard.. with her speed and inertia... Hmmm
I think your explanasion is logical however surprised they managed to restart the main engine astern so soon after blackout. would have thought prop still rotating wrong direction when main engine shut off on blackout. My boat suffers significant prop walk when going astern which can be useful going alongside. Would the bow thruster not work at all above 5 knots ?
@@MustaphaZehhaf Hi I believe it took nearly a minute to get power back from the emergency generator. That would give power to restart a generator which were quite large e.g 4000+ hp. That would need to be on line to enable restart of main engine and likely prop still turning due to 7-8knots motion. Suspect would not be enough time to restart astern before collision. Believe black smoke is generator restart. Do agree that a restart of ME could probably cause turn to stbd. If not achieved then maybe anchor.
Hi Mustapha, My question is this: If the Pilot would not have turned the power back on, would the rudder have been just like it were before the power failure, would he just coast right under the Bridge continuously but only coasting and then as he would nearly be cleared, then try and restart, does any of this make sense? Thanks for your Time. I'm glad to ask this to an expert. Thanks for your effort to help us folks to understand these things. Terry age 65
What are you saying? Rudder will be in Midships? I don't understand ship language, so what does that has to do with just coasting towards the bridge with No power? Terry at 65
I agree. The smoke was full reverse. Not a captain Have served on a ocean going tug heavy duty search and rescue. The timing and the failed to proximity to bridge is uncanny.
Thank you for addressing the likely cause of the starboard turn, or maybe more importantly, the unlikely causes others have thrown out there. I don’t know if it’s an overreaction to the initial shock and subsequent creative explanations (it’s the internet, who knows the motivation or even if it’s real people), but some channels went a little heavy with those first few theories you mentioned.
Question: If the ship had steered for bank suction and / or the effects of the prop, they would have started to turn slowly starboard when they lost power. Then, if they went full astern it would have made it worse. The AIS data seems to suggest this with a slight starboard turn then the turn increases. I haven't been able to match them up with power loss and the black smoke, so I'm just guessing from my limited experience handling an old 50' single screw fishing boat. It had a 6:1 reduction and 43" diameter prop and would walk the stern pretty well. By going forward and backwards you can spin her in just about her boat length. Forward just to stop any reward movement then hard astern to walk the stern around. Eventually she'd start going backwards so you'd give her a little forward then hard astern. Keep repeating and you go in a circle. Is it possible she had a little right rudder dialed in to keep her straight, and is so, how long till the pressure in the steering bleeds off and the rudder goes amidships? Is it possible in the 60 seconds or so that she lost power it stayed in the same position? And then if they went full astern it wouldn't matter where the rudder was because it's not effective. Is it standard procedure to drop the anchor at a time like that? Or was that just captains discretion? Also, at 8.5 kts I'd expect the stopping speed to be over a mile - far more distance than to the bridge when they lost power.
Typically, what information will be recorded on the Voyage Data Recorder (VDR)? Based on NTSB comments, it appears the VDR has a separate UPS to allow it to work during a power outage, NTSB stated it kept recording bridge commands so assume it has a working UPS. Does VDR get any data from engine room systems during power outage? Do engine room systems have their own internal data recorders? PS- After the ship dropped the plant, how much time does it take to restart the diesel engine in the reverse direction? Aren’t these diesels directly attracted / geared to the shaft? It would seem the event time between loosing power and hitting the bridge was too short a time to order engine astern, stop the diesel engine rotation and restart in opposite direction. PS2 - Thanks for making this video
The captain may have ultimate responsibility but that fact exists assuming there's a malicious pilot or other major issue. A pilot making a mistake means its the pilot's fault. If a nurse causes complications in your surgery, you don't blame the surgeon even though he's ultimately responsible.
Thank you Captain excellent explanation as ex ch/engineer will be interesting to find out what went wrong down in the engine room, based on your explanation the pilots order should be in my opinion " hard starboard and full ahead" rather then full astern
Most of the time, it is a combination of factors causing an accident. I think you may be underestimating the wind, because when you look at the smoke out of the funnel, it is forced to starboard almost at a right angle. If the pilot or captain backed the engines and at the same time had the rudder to port, if the ship started backing, the ship would start moving to starboard, so the combination of wind, propeller and rudder might have resulted in the sudden turn to starboard. I am not sure the anchor would have had any effect on such a large ship moving at 8 knots. However, the largest ship I ever conned was a steam powered WWII era destroyer with two propellers.
Captain, it apears from the comments that it might be advisable for you to take us step by step through procdures necessary to reverse propellor. Also it seems unlikely to me that the engines were restarted in so short a time, and if so why the captain and pilots would reverse prop with sacrifice of control. Or, would it be a panic move? Were they too close to collision to regain steerage by forward thrust??? Is it true that there is a delay in prop water against the rudder before significant turn response is appreciated? Also, do we have available figures for water flow from that starboard river at that hour given the tide conditions?
Thank you for this informative video! So could there have been a chance the ship would have went straight and missed the bridge if the engine was not put in reverse?
You say you are a Master mariner Right. In your opening gambit you state the master must obey the Pilot and not interfere with his activates, Then you go on to say the Pilot is there to advise only. You can’t have both.
Pilotage is mandatory for certain Vessels; but the pilot is there only to advise, and will NEVER be held responsible for the outcome, what a lovely position to have you can basically say what you want with no responsibility. That is crazy. By the way they are not orders it is advise. Most times it works BUT when it doesn't then the pirate should be held responsible for his or her actions, read the recording of the Ever Given, the pilots were at loggerheads with each other AND speaking in their own language. @@MustaphaZehhaf
Even if they did not go astern wouldn’t the rudder be slightly starboard to compensate for the propeller kick? So losing power removed the prop but now the rudder is to starboard and can’t be moved amidships? Either way this is the best explanation of the turn I have seen
@@MustaphaZehhaf I mean if the engine is running forward and pushing to port so the vessel has a slight starboard trim. Then loses propulsion and power so the kick from the prop goes away but the rudder trim is still slightly starboard.
Thank you for the video, I have a "few" questions :) From what I have learned in other sources, the turn looks a lot larger from that video then it actually was. Would a much smaller turn (angle) change any of your conclusions? (I'm suspecting not). How many degrees of turn was actually needed from where they lost power to hit the bridge? You sad the wind wouldn't have mattered, how accurate is that wind data for different heights above water/ground? While 5-7 knots of wind is light, it would be more then doubled by the speed of the vessel I would think? Does that change anything? Would the bridge and land around it not have likely "shaped" the wind to not be the "normal" direction? Are the cargo containers stacked in a wind-neutral arrangement, or could those catch wind differently enough to create a turning force? Even if we were to assume the wind was straight from the worst angle, how much of a turning motion would that impart vs just pushing the ship sideways without turning her? Do you think that them not hitting the bridge head on, but from the side mattered? As they have been grounded, would a head-on collision potentially ground then before they reach the bridge pillar(s)? How far up on land would a ship this size and weight get before stopping? And the bank effect, a large question about that is the second smaller channel on the south side? How do you think that would play into it here? Also, how much steering capability is left without any propeller wash on such a large vessel? I suspect that the rudder(s) are above the keel of the vessel? I started to question this after a different video by someone also working on a large vessel, although in a different role. One last question, and IMO the most important one: Lots of talk about "why no tugs". At these speeds, how much can "normal" tugs do? How high would the risks for tugboats be if connected to a ship of this size and speed? I think it's easy to only look at the idea of tugboats saving the day, but would they even have been able to do so without taking massive risks? No need to answer all of them, but all answers will be appreciated!
I saw on other videos that there was electrical problems. The captin should not have been made to leave the port with things not working right. If you go on a car trip with your family and you need a new tire you wait and get a new tire. By right the captine is legally boxed in by having to work with a ship that was not 100%.
The ship owners or operators are not responsible for the Maryland Transportation Department NOT ensuring that the bridge across a busy port with huge ships was adequately protected from damage by collision / allision. Rebuild costs for the bridge should be for the same standard of bridge NOT full cost of a new superbridge… let the state or Federal Government pay for that.
The question is if the engine was actually in reverse. Engineer Makoi - an expert in his own ship, doesn't think it was started and explains why. The walking propellor theory makes a lot of sense for sure and that with the black smoke looks like a smoking gun. He says that to reverse the engine is not an instantaneouos thing - it is complicated especially after the blackout. At the end of the day, the recorder will tell us.
10:21 The ebb tide can only be excluded if the tides were normal. The previous high tide caused flooding on the East coast so you can't just toss the ebb tide.
@@MustaphaZehhaf Yes, the previous high tide flooded the Indian River Bridge that was really an inlet to another bridge. ua-cam.com/video/P45gtBQBgwg/v-deo.html
Captain, the propeller effect would not cause that drastic of a turn and a pilot or captain would have stopped the engine if it did. Emergency power is to keep up the hydrolic pressure in the rudder ram as well as power the helm. If they did nothing and the ship was on course with momentum it would have cleared the bridge while they continued corrective actions.
I have seen another informed analysis which disagrees about the generator and engine behaviour, mostly by looking at the smoke and which lights came back on. He says the emergency generator never came on (due to the time delay and non-emergency lights coming on), instead a backup generator started and then later quit. He says the main engine never restarted in reverse or forward… the very strange black smoke indicates that. For me the severe swing into the bridge was caused by something that was INTENDED to turn the ship quickly, i.e. the steering gear, you say in the video that without hydraulics the rudder will self-centre and not remain in position but if a turn command was made but not actioned due to the power loss then it might have suddenly turned when power came back on. In any case the massive ship would have continued straight along the channel at 7-8 knots and safely under the bridge if they had just left it alone and restored the power systematically. They couldn’t have done a better job of destroying the bridge if they tried….
Sir, at 10:16 you state that the south east wind was "opposite to the ship's direction and therefore would not slow down the vessel". But south east was also the direction of the ship, therefore the ship was running before the wind, not oppositely.
Thanks for the explonation here and as I did say this in my previous comments and most likely you did gather all relevand information the course of the collision was going full astern and that explain also the thick black smoke from the main engine going full astern. That is the moment that is clearly visible on the pictures the movement of the vessel to starboard with this kind of propeller going in the astern position but she had a fixed propeller so the blades where welded to the shaft. My theory therefore was correct and the blame is with the person giving this command from the bridge as the chief engineer don't do that by himself unless he is ordered to do so. Makes a long story short in this case, YES it was a human error by giving the wrong command to the ER / main engine. I'm also pretty sure that if they just give the engine dead slow ahead with little port rudder she would have safely passed the bridge. The anchor on ps did NOT give any effect to the vessel as it did not even touched the bottom and for that we have pictures how the chain was going strait down in the water after the collision. So Mustapha, you and me came to the same conclusion. Now in your next video just show us the course line 140 degrees until the first black-out and what would have happened with the scenario as I descriped it, sure we are on the same line. Sorry for the master if he did give that command full astern knowing he (the vessel) did have a right handed propeller. Told you I'm already an old man 76 but this is something that every master should know and sure in this event use his brain what will happen. He (the master) is to blame as he don't know his ship where he is sailing on. Sorry for the 6 dead road workers but the master should be arrested and look into his experience sailing with ANY vessel this size and what it is doing going astern. Anyway, looking forward to your further investigation, as one master to another, keep it safe.
@@MustaphaZehhaf it was possible that they changed back to main power from EG as then you have a small little black-out as changing over with the tripper switch. But then again, as fumes where not stopped but only the light did change and came back on and so you need to see on the ER computoer what really happen. But sure this was the case changing back to "normal " power. But look into the course line of 140 and maybe you have a simulator there and can do this with NO ASTERN given.
thank you for your explantions, I concur with you. one question though, the anchor cable is verticle from the hausse pipe. had the anchor been dropped further back, even if it didnt 'dig in', the cable should be still lying tight and toward the stern. Given the wreckage and damage on the fore deck, I do not believe that the anchor wil have been released post colision. your thoughts please
@@MustaphaZehhaf thanks, my thoughts too, which means the anchor had no part to play in the position or placement of the vessel. (where is the Stb Anchor? cant even find it in the high reso pics)
Thank you, Captain. For me, being on the lifelong curve of professional development as a shipbuilding, offshore operations and engineering management professional with 25 years experience behind my belt, you still have managed to show me some pretty much useful information.
You're welcome, appreciate your nice words 🙏
What an explanation ! No one could cover the incident with such depth !
Thanks for your time Captain bringing all these details.
You're welcome, happy to read this 🙏
Congradulation for your explanations examining every possible cause of the accident. I'm not a captain but a mechanical engineer and I appreciated you explaining the hydrodynamic forces to the propeller causing the ship to turn starboard.
You're welcome, thanks 👍
Thank you sir. Thats the best explanation of this incident that I've read so far. I'm ex Navy. (Gunners Mate) I learned basic seamanship and worked on hydraulic and hydro-electric motors. The steering explanation was spot on and brought me back memories of changing those heavy motors out and refilling hydraulic fluid. New subscriber.
Thanks and welcome to my channel
As retired US Navy ship driver I agree with you 100%, great explanation.
Thanks 👍
I had single screw ship experience in the navy and his analysis is spot on. Had the ship not backed down until it cleared the bridge, it would not have hit the bridge. At its distance to the bridge at time of failure, and the distance a ship will stop when going 8 knots, backing only compounded the problem. Just my opinion after years at sea on naval ships.
Based on the video that's now universally available of the failure and collision, the ship essentially lost power at the absolutely worst possible time to lose power. Even had she not gone back full, a collision was likely, as bank effects are present also from the piers themselves, as well as the dolphins nearby.
But, excellent situational awareness allowed the pilot to call on the radio of a potential collision, preventing an even greater loss of life. That class of vessel turns on a really, really, really large dime.
Having driven on that bridge quite a few times in military convoys, they got traffic shut down just barely in time!
Thank you for such a detailed and accurate description of what may or may not have happened from someone who clearly knows what actually happens on ships of this type.
It certainly debunks some of the other theories from so called experts.
You're welcome 🙏
Thank you Captain. Very well broken down to all of us in Baltimore, We appreciate you
Happy to connect with you and sorry for what happened in your city.
@@MustaphaZehhaf Thank you sir, AAnd agian thank you for for everything you do, be safe out there
Exceptional explanation! Thank you for this. You made things much clearer, and I appreciate that.
Thank you Captain Zehhaf.
Very nice work.
Thanks
A good set of examples. You and I are in agreement. I have been telling people from day one that ship was not steered into the bridge, that the black smoke is most likely caused by the ship being placed full astern, which would cause the vessel bow to turn to starboard. This was an accident.
The primary reason that the bridge went down is that the bridge protection system was/is totally inadequate.
The bridge's protection system consisted of four, too few and too small, dolphins, two on either side of the bridge, and a wooden & steel fendering system around the bridge support legs. This protection system was designed to protect the bridge from much smaller, much lower hulled, ships than those of today. The government's neglect in updating the bridge protection system is mostly to blame for the loss of the bridge.
Those who disagree, that the government is mostly to blame, I would like to you consider. Ships must travel on water. They cannot go around. Vehicles and trains operate on land. When they decide to build a bridge they must make allowance for the types of vessels that will continue to use the waterway. This bridge has been hit in the past and the risk of it being hit again will always be there.
Absolutely, they stuck the bridge in the way of established marine traffic from a major port. Maryland State and Governor should immediately foot the bill for protecting or replacing the other vital Chesapeake bridges or they have no business blaming the ship for the scale of the disaster and running off whining to Joe Biden.
Most logical explanation, and I fully agree with you Captain. Bravo!
That was exactly my thinking when I saw the sudden turn of the Dali and the smoke rising from the funnel. So I see it confirmed by a way more knowledgeable person now. Thanks you!
👍
Thank you for your explanation of the various crash theories.
What a well explained video! I'm excited to watch more! I also had trouble with how fast you speak although your English is easy to understand. I'm not in maritime or an engineer and yet you made this complex topic easy to understand- thank you for all the extra graphics and showing actual engines! You remind me of Mentor Pilot. Wishing you much success!
Thanks and taking notes about the speed haha
Nice one! Thanks for sharing your knowledge..
Hi @Mustapha could I suggest speaking slightly slower or else adjusting the video setting so that playback is at 80 or 90% of your actual speaking rate. I have an add-on to my browser that lets me do that at my end, but most people are stuck with UA-cam's primitive Normal 75%, 50%, Normal, 125%, 150%. And most people won't even think to adjust the speed. I'm a native English speaker, I work in IT in Toronto, I've worked with people with lots of accents. Your English is fine, just a little too fast. I think slowing the playback speed slightly will help boost your viewer numbers.
Anyway, great video, keep up the good work !
Thanks for your valuable feedback, I'll try to slow down a bit during the next videos.
Being an impatient person, and one who also has been exposed to many non-native English speakers, I actually sped up the video to 1.5 speed. I usually listen to news and informative videos at 2X speed but because of the unfamiliar accent, 2X was a bit too fast for my ears. Captain, keep up the good work!
I use closed captioning, as my hearing loss tends to make even fairly accentless English a bit difficult to track at times.
I slowed it down by 25% and he Sounded just fine, These old Ears can not hear that fast HAAHHAhaah
Great channel, very knowledgeable. Good video of how these ships work too! 10/10
Thanks 🙏
Great video! Thank you! Stay safe out there!
You are absolutely correct, thank you Captain
You are very welcome
Good job Captain. A lot explained in a short time. All other “Baltimore” experts would have split this video into 10 parts to earn more revenue.
It will be useful to further elaborate on the 3 most probable causes with additional scientific back-up. It will help NTSB to temper their findings to non-biased outcomes.
Thanks 🙏
Thank you sir for taking the time to explain, very informative...sometimes it feels like our media is lacking on purpose to create and facilitate conspiracy with their lack of logical detail. Thank you.
Welcome, thanks.
you’re absolutely right, the transverse thrust effect turned head to starboard while steering alone could save the pilar
Very Informative, I learned alot, very quickly and agree. Thanks
Glad you enjoyed it!
Thanks for the engineering analysis. Subscribed.
Thanks :)
Very well explained… thank-you.
I learned a lot - when you explained the unbalanced forces on the shaft due to the water pressure … click! Seems a very plausible explanation. Now we wait for the NTSB report.
Happy to read this 🙏
The editing and explanation are amazing. Keep going!
Thanks Yahia 🙏
Remaining the thumbnails now 😁
@@MustaphaZehhaf You're most welcome!
And just one by one bro.. Take your time
Thank you very much captain!!! Very detailed video. I've seen similar theory from a different captain, but without such detailed explanation. Based on this logic it seemed most probable case. There are so many details that are very evident for the professionals that are supporting this logic and this theory. The another captain also pointed that a speed of the vessel had dropped to five mile an hour or so, before collision. That is also supports this theory. Just recently, another ship lost it propulsion at New York port, but everything worked out safely.
You're welcome 🙏
Practical analysis. I agree with your explanations.
Thanks
Thank u for more info😀
Welcome, thanks 👍
I listen to most YT videos at 1.25 speed, some at 1.5. I had to slow this one to 0.75 speed. Good info.
Positive or negative point ? 😁
@@MustaphaZehhaf It's a little bit of a complaint because I have difficulty understanding your accent. Though I was pleased to get the information, so I slowed it down to understand it.
Yes, I also had trouble with his fast talking. Didn't know that is an option, so I will try that!
Great video explanation!
Thanks Capt
Very correct demonstration ;) But I wonder why they would have reversed the engine since the vessel was correctly in the channel? This action, if verified, causes the accident.
Stress and panic affect our instant thinking
In your theory you forgot the time needed to restart the main engine. First of all they had to restart cooling water,fuel pumps,lubrication pumps,etc. With a speed of 7 to 8 knots the motion of the ship through the water would still turn the propeller around and it would be difficult to stop it so that the engine could go astern. Besides ships that size would have a blockage to prevent the engine to be turned astern if the speed through the water is too high. This can be manually overridden but by doing so you risk breaking the engine down. Besides so close to the bridge it would be too little too late. I noticed in your clip you showed pictures from a LNG tanker of the Moss - Rosenberg type. That would have a steam turbine that would be even more difficult to turn astern without breaking it if the ship is doing the mention speed through the water. Let’s assume they managed to get the main engine up and running again. The logic thing to do would be to give a kick ahead so that you could steer clear of the bridge. At this time the heads of both those in the engine room and on the bridge were probably boiling due to the situation and the noise from all the audible alarms. The smoke that you see is probably from the auxiliary engines being restarted.
Poor bastards, they had less than 5 min from first power out to under the bridge.
Any ship can go astern while still sailing ahead. It is mandatory and tested at the sea trial. So I don’t understand why everybody is talking about this thing about the propeller still turning ahead would prevent to go astern. Also I am a combined chief engineer and I can tell you that steam turbines react faster and better in those situation. We never break the engine when going ahead then astern. This is something we do regularly during manœuvrons in port anyway.
@@captcarlos it must have been five very long minutes. You know what will happen but there is little or nothing you can do about it. Thankfully the people on the ship’s bridge managed to send a message ashore so that they could stop all traffic and thanks to the police that reacted quickly and prevented even more casualties.
@@gaetansimard1594 With a small boat you can do that but not with a large ship engine. Yes , they test the engines astern on the sea trial but not at 8 knots ahead. On a large ship each cylinder might have a bore of 80 centimeter and a piston stroke of 2 meters. If you also add the fact that these engines also have 6 or more cylinders it is understandable large things we are talking about. Steam engines are stronger than diesel engines but they are also more delicate and must be handled thereafter. I have been a seaman for more than forty years, the last 23 of them as master, so I know a thing or two about handling large ships. My experience is both steam and diesel powered engines. If I tried to go astern when the ship was doing 8 knots I would probably break the engine and give the chief engineer a heart attack. Besides when you go astern with a large vessel you basically have no steering at all. What could save the situation is to give the engine a kick ahead to gain control of the heading but in this case I find it unlikely that they could manage to get the main engine available in the short time they had at their disposal. The first thing they would have to do is start an auxiliary engine and then synchronize it and connect it to the switchboard. This could be the reason why they had the second blackout. Then they would have to all the auxiliary systems to the main engine running before they could attempt to start it. A normal procedure is also to blow through the engine with starting air before attempting to start it but in this case it was a do or die situation,so they would have cancelled that. Starting air could have stopped the propeller from spinning long enough to attempt a start but it would be very risky. Even though they were sitting in a modern control room where most things in the engine could be operated remotely it still would take some time. An interesting question is if any breakers tripped.
I am pretty sure that all of the fact will be revealed when the official report is published.
Do you mean if the vessel is sailing at full speed and encounters an emergency, she needs to slow down and stop then reverse? Of course NO, in case of emergency, the engine is there for these cases.
A very good explanation captain Mustapha , good Luck
Thanks, appreciate it.
I agree with your reasoning. Further evidence supporting the full astern hypothesis is that ship heading didn't change at all for the full minute the ship was blacked out, and then it started to turn starboard right after some lights came back on and then the black smoke started coming from the stack.
But a couple questions:
- Is it plausible that the main engine was restarted in just 1 minute? One Chief Engineer on UA-cam thinks not.
- Could the current from the Curtis Bay side channel have turned the ship?
Yes you can start a warm main engine within seconds if you get the auxiliary running (LO pump and fuel module unit) cooling water pumps is sometimes needed but not always. If the main engine overheat you have warning the shut-down. But it can take a few minutes before reaching shut-down at slow speed.
@@gaetansimard1594it's much harder to start the engine in reverse when the ship is moving forward though. The water on the propeller tries to push the engine to run forwards. It would be quite easy to start running forwards, but hard to start running in reverse.
@gaetansimard1594 the engineer also gave a time line to restart and believes the shutdown was fuel related which is why the 3 engines (2 generators and main) shutdown and the backup didn't come online. He also believes that according to the visual time-line that the black smoke was from one of the main generators
Nice video. I like the examination of different forces /causes /scenarios side-by-side. It would be interesting to know if the command was ever issued to go full astern, or if that is even possible in a tight timeframe. Would an observer see churning of the water under such conditions Another piece of information that would be interesting , would be the captains view of the harbor at night: how does he see the waterway, the obstacles , navigation markings/lights & charts wrt things to avoid, geographic points of interest, etc. as he makes his way out of the harbor
Great Topic : View of the harbor at night.
@@MustaphaZehhaf in particular: Not so much what was visible, but what could not be determined -- warning buoys, pier markings, boundaries of the channel, etc. I know the center channel light on the bridge looks pretty obvious. But what else gave them warning that they were dangerously close to the pier of the bridge. Were there markings on the high tension lines just before the bridge, etc, etc.
refreshing and enlightening to hear a technical analysis of this incident. Thank you Captain! Looking forward to further learning.
Welcome, thanks 👍
Nice one - well explained !
Thanks
Well explained👍👍 you are the best captain , your name truly suits your leadership qualities and command presence ❤
Oh thanks, really appreciate it 🙏
I agree totally that it was prop thrust while in reverse! Great video! Thank you
Thanks
I tend to agree with your hypnosis and would add that the tidal flow from the Curtis Bay channel adds to the impetus to swing the Stern to Starboard.
Not to be hypercritical but its hypothesis. Not hypnosis. He offered a hypothesis on the hypotenuse angle of the ship’s travel, he didn’t hypnotize or alter your state of mind.
I agree. The deep black smoke is main engine full astern, and the captain "prop-walked" his ship into the bridge.
Single prop aircraft do the same thing.
Interesting, very interesting.
Thanks
obiously u are correct.pitch propeller with engine MAN,rapid swing to stb mean power ME back ,huge smoke as result od full astern.surprice no any usa institution until now present
such significant move.
😀
A lot for a non mariner to digest but I do understand all your 5 theories and with your summation. Now, next, what caused the initial shutdown?
Difficult to say without investigation
Yes thank you, very plausible. M
You're very welcome
I would agree about the prop thrust..however a marine engineer (who actively works similar ships) stated that with the resets needed that by the time the generator was started there wasn't time to restart the engine.
Everything else you state aligns with what you stated.
I am a combine chief engineer (steam and diesel) 30 years experience. I also think they that they started the main engine full astern, this is the black smoke, and that cause the ship to turn to starboard. Also think that it was not the emergency generator that kik in but one of the main. You need the main generator to start the main engine on a slow speed engine. You need the LO pump and the some aux equipment that are not supply by the emergency generator. But how they got the ship to blackout is still a mistery. Normally they should have two generators on the board during Stby and run on MDO. Probably a humain error.
I have limited knowledge about the engine but there is theory about FO change which led to the black out.
This video just turned up in my suggested videos and at the start you suggested watching the previous video first and I did. Since this incident happened I've become more interested in how these large ships navigate. I've been picking up bits and pieces from various videos. I found yours more of an in depth explanation of the various things in play. I hadn't heard that the emergency generator is required to come on in 45 seconds. I had known that a rudder needs water flowing past it to have much effect so when the large propeller stops it blocks much of the flow. From the timeline in some other videos, the Dali appeared to start turning to starboard before power was lost or they had the timeline wrong for when power was lost. How much forward speed would a ship that size need for the rudder to be effective and how effective could it be with the propeller stopped? If they did reverse the engine, how much distance would be covered before the ship slowed significantly? Wouldn't the pilots and captain know that reversing the engine would cause the rudder to be ineffective? I've subscribed to see more and I will watch some of your other videos.
Thanks for subscribing.
Sometimes, in moments of panic, the actions are random.
@@MustaphaZehhaf Do people who reach the position of Captain of such a large ship panic? Seems like they would have been weeded out.
Fascinating 🙏
the Dali has a direct shaft to prop drive. It takes time to start the engine in reverse and ramp up power -- more time than they had. It also causes cavitation which reduces prop effectiveness. The proper course of action would be to increase speed ahead which counterintuitively would swing the bow to port.
Do you mean in emergencies you need to wait the Shaft to stop to reverse? I don't think so ...
I really wish the NTSB would announce the results of its tests on Dali's fuel so that other ships that had bunkered in some of the same ports as Dali would know if they can rely on the fuel in their tanks. It seems insane to me that ships are running around out there unsure if their fuel is contaminated.
There is a theory about FO change over !
I've never piloted ships but I've piloted cruising sailboats for decades thus I'm well aware of transverse thrust (aka prop walk) so, while recognizing there may be some large ship dynamic I'm unaware of, when I saw the stern swing to port and the black smoke I immediately thought of prop walk. I then checked to see if Dali was single screw and discovered she is, hence transverse thrust causing the turn remained my suspicion. Your analysis as a ship captain who would know of any big ship dynamics I'm not familiar with is most interesting.
What I really can't understand is, if rudder control was lost, why the pilot or captain didn't employ the ship's momentum to clear the bridge.
Sometimes panic and stress are overwhelming hence the mistakes will follow
Excellent analysis Captain
@15:55 he places his "bet" of what made the ship steer into the bridge
Whole video is interesting and worth watching
Thanks
This has puzzled me from the very early days after the accident. If it is known that reversing the propeller will cause both the stern to swing from line of travel and for the rudder to become irrelevant, why would anyone who knew what they were doing reverse the propeller due to a loss of power on the approach to a bridge? The ship was clearly not a danger to hit the bridge until the turn, so why command a reversal of the prop which is known to cause a turn which can't be countered by the rudder?
I've played with boats for a long time and know for certain that a loss of power means the boat will continue in a straight line and clearly the pilot and master were aware of this as well, so why did they reverse the propeller? It just doesn't make sense unless they were completely incompetent or desired to hit the bridge.
So interesting
Thanks
Very good explanation Captain -Totally agree with your event and ship movement factual analysis based on correct theory, but in relation to the law the USA do not apply the LLMC convention version - they apply a US Version of shipping limitation liability which is similar in concept but not the same ( differs in calculation value unit, and slightly differs in what it covers). By the way good see another Moss-Rosberg LNG ship - I served on a 4 dome and 5 dome versions.
Ah yes, USA has more requirements usually.
Thanks LNG mate 😊
Interesting spin. Walking of the prop in astern propulsion.
Of course the Captain is entirely responsible and will be held accountable. The Captain is the leader and if in ANYWAY a lack of his leadership, in any facet, caused the accident it is his responsibility. Misplaced faith in CHENG's leadership, CHENG's faith in an engineer, a trainee turning a wrong valve, somebody not doing their job or falsifying a report. It's all the Captains responsibility.
Some are saying that they did not have time to restart the engines in reverse but what you are saying makes more sense to me.
Here's my theory. Using the Marine Traffic AIS course track it's clear that there were two course changes. The first one occurs at the initial loss of power and consists of about an 8 deg overall slow veering turn to starboard. This turn initiates while the Dali is passing to starboard the open entrance of the Curtis Bay channel. The veering could plausibly have been the result of the last commanded rudder correction before the first power outage. In using the term veering I am implying that this first turn was a slow and continuous clockwise (from above) rotational movement pivoting on the ships CG. This seems to be indicated by the AIS course direction updates (gradual heading changes to starboard over the distance to the second course change). The second course change occurs just shortly after the anchor is released. This second turn occurs much quicker and over a very short distance when compared to the first veering turn. It was approximately 9-10 deg. The total course change to impact was from 140 to 159 more or less. I posit that while the release of the anchor would have almost no effect on reducing the speed of the ship it may have generated enough resisting force by contact with the bottom to accelerate the small clockwise veering moment that the Dali was already experiencing. In other words the Dali was suddenly, by the drag of her anchor, tripping over her toe. Keep in mind that the anchor chain drops out of the hull closer to the midline than to the sheer line and it's plausible that the anchor quickly got under the hull into a favorable position on the starboard side of the midline, increasing, through drag and leverage advantage, the clockwise moment. I do not believe the second course change was caused by propellor walk nor do I believe that the main propulsion engine was ever successfully restarted. I do recognize that arriving at those conclusions is plausibly constructible from the video evidence but I find as a theory it lacks persuasive support from chief engineers.
Do you think dropping the port anchor can swing the vessel to stbd ?
Is it important for the bank effect that a side channel was opening to ship starboard (rather abruptly) just before the bridge, seemingly where she did turn ?
As long as there is an open water the bank effect fades
@@MustaphaZehhaf so if the bank effect fades, allowing the stern to come to port, combined with a possible flow from the incoming channel, also pushing the stern to port, combined with the reverse engine and the propellors effect, turning the ships bow to starboard.. with her speed and inertia... Hmmm
Wonderful summation of the complexity the lawyers will feast on..
Just How do you slam it into reverse at seven (7) knots..?
4 1/2 min, the pressure.
At the first black out the engine stopped, they may put the engine to stop and then reverse to astern when the power came back.
I think your explanasion is logical however surprised they managed to restart the main engine astern so soon after blackout. would have thought prop still rotating wrong direction when main engine shut off on blackout. My boat suffers significant prop walk when going astern which can be useful going alongside. Would the bow thruster not work at all above 5 knots ?
The vessel is designed to reverse in emergencies
@@MustaphaZehhaf Hi I believe it took nearly a minute to get power back from the emergency generator.
That would give power to restart a generator which were quite large e.g 4000+ hp. That would need to be on line to enable restart of main engine and likely prop still turning due to 7-8knots motion. Suspect would not be enough time to restart astern before collision. Believe black smoke is generator restart. Do agree that a restart of ME could probably cause turn to stbd. If not achieved then maybe anchor.
Hi Mustapha, My question is this: If the Pilot would not have turned the power back on, would the rudder have been just like it were before the power failure, would he just coast right under the Bridge continuously but only coasting and then as he would nearly be cleared, then try and restart, does any of this make sense? Thanks for your Time. I'm glad to ask this to an expert. Thanks for your effort to help us folks to understand these things. Terry age 65
When the black out happens there is no hydraulic oil pressure hence the rudder will be in midships
What are you saying? Rudder will be in Midships? I don't understand ship language, so what does that has to do with just coasting towards the bridge with No power? Terry at 65
great vid. subbed. thanks
Welcome!
I agree. The smoke was full reverse. Not a captain Have served on a ocean going tug heavy duty search and rescue. The timing and the failed to proximity to bridge is uncanny.
Thank you for addressing the likely cause of the starboard turn, or maybe more importantly, the unlikely causes others have thrown out there. I don’t know if it’s an overreaction to the initial shock and subsequent creative explanations (it’s the internet, who knows the motivation or even if it’s real people), but some channels went a little heavy with those first few theories you mentioned.
Yes, some crazy theories are out there
Question: If the ship had steered for bank suction and / or the effects of the prop, they would have started to turn slowly starboard when they lost power. Then, if they went full astern it would have made it worse. The AIS data seems to suggest this with a slight starboard turn then the turn increases. I haven't been able to match them up with power loss and the black smoke, so I'm just guessing from my limited experience handling an old 50' single screw fishing boat. It had a 6:1 reduction and 43" diameter prop and would walk the stern pretty well. By going forward and backwards you can spin her in just about her boat length. Forward just to stop any reward movement then hard astern to walk the stern around. Eventually she'd start going backwards so you'd give her a little forward then hard astern. Keep repeating and you go in a circle.
Is it possible she had a little right rudder dialed in to keep her straight, and is so, how long till the pressure in the steering bleeds off and the rudder goes amidships? Is it possible in the 60 seconds or so that she lost power it stayed in the same position? And then if they went full astern it wouldn't matter where the rudder was because it's not effective.
Is it standard procedure to drop the anchor at a time like that? Or was that just captains discretion?
Also, at 8.5 kts I'd expect the stopping speed to be over a mile - far more distance than to the bridge when they lost power.
In a moment of panic, all solutions seem correct 💯
Typically, what information will be recorded on the Voyage Data Recorder (VDR)? Based on NTSB comments, it appears the VDR has a separate UPS to allow it to work during a power outage, NTSB stated it kept recording bridge commands so assume it has a working UPS. Does VDR get any data from engine room systems during power outage? Do engine room systems have their own internal data recorders?
PS- After the ship dropped the plant, how much time does it take to restart the diesel engine in the reverse direction? Aren’t these diesels directly attracted / geared to the shaft? It would seem the event time between loosing power and hitting the bridge was too short a time to order engine astern, stop the diesel engine rotation and restart in opposite direction.
PS2 - Thanks for making this video
The VDR doesn't record engine movement, only data from navigation and communication equipment.
Very interesting. Is this similar to P-Factor in propeller driven airplanes at high angles of attack?
The captain may have ultimate responsibility but that fact exists assuming there's a malicious pilot or other major issue. A pilot making a mistake means its the pilot's fault. If a nurse causes complications in your surgery, you don't blame the surgeon even though he's ultimately responsible.
It's not the same, this is the maritime law
I like all that you said and agree on final reversal of prop to low ship, however why did it not continue turning and run aground on right bank?
The ship had another blackout
Thank you Captain excellent explanation as ex ch/engineer will be interesting to find out what went wrong down in the engine room, based on your explanation the pilots order should be in my opinion " hard starboard and full ahead" rather then full astern
Most of the time, it is a combination of factors causing an accident. I think you may be underestimating the wind, because when you look at the smoke out of the funnel, it is forced to starboard almost at a right angle.
If the pilot or captain backed the engines and at the same time had the rudder to port, if the ship started backing, the ship would start moving to starboard, so the combination of wind, propeller and rudder might have resulted in the sudden turn to starboard.
I am not sure the anchor would have had any effect on such a large ship moving at 8 knots.
However, the largest ship I ever conned was a steam powered WWII era destroyer with two propellers.
WWI II destroyer ! My pleasure to have you here.
What is the protocol for entering and leaving a port ?do they have to have a pilot boat or tug to guide a ship out of port ?
Usually entering and leaving a port using pilot and tugs
Captain, it apears from the comments that it might be advisable for you to take us step by step through procdures necessary to reverse propellor. Also it seems unlikely to me that the engines were restarted in so short a time, and if so why the captain and pilots would reverse prop with sacrifice of control. Or, would it be a panic move? Were they too close to collision to regain steerage by forward thrust??? Is it true that there is a delay in prop water against the rudder before significant turn response is appreciated? Also, do we have available figures for water flow from that starboard river at that hour given the tide conditions?
Thank you for this informative video! So could there have been a chance the ship would have went straight and missed the bridge if the engine was not put in reverse?
Yes, but this is only a theory
Would the black smoke from the exhaust not rise at a straighter angle in a five kn wind? The exhaust seems to immediately be bent to a right angle.
Vessel movement 8 kts + Wind 5 kts = Relative wind 13 kts
You need to talk about the bow thruster......
I covered it briefly in this video
You say you are a Master mariner Right. In your opening gambit you state the master must obey the Pilot and not interfere with his activates, Then you go on to say the Pilot is there to advise only.
You can’t have both.
You can have both, pilotage is mandatory, hence you need to follow the Pilot's orders unless they are unsafe therefore you need to intervene.
Pilotage is mandatory for certain Vessels; but the pilot is there only to advise, and will NEVER be held responsible for the outcome, what a lovely position to have you can basically say what you want with no responsibility. That is crazy. By the way they are not orders it is advise. Most times it works BUT when it doesn't then the pirate should be held responsible for his or her actions, read the recording of the Ever Given, the pilots were at loggerheads with each other AND speaking in their own language.
@@MustaphaZehhaf
I agree with you regarding the reason. But I only have one Question. When were the tugs released or were they even thete in the first placed??
Yes, they were released once the vessel entered the channel.
Please check out my previous video, I answered this question.
Good theory ….i think it’s correct if there’s no malfeasance
Even if they did not go astern wouldn’t the rudder be slightly starboard to compensate for the propeller kick? So losing power removed the prop but now the rudder is to starboard and can’t be moved amidships?
Either way this is the best explanation of the turn I have seen
The rudder doesn't have a noticeable effect when the engine is running astern
@@MustaphaZehhaf I mean if the engine is running forward and pushing to port so the vessel has a slight starboard trim. Then loses propulsion and power so the kick from the prop goes away but the rudder trim is still slightly starboard.
Thank you for the video, I have a "few" questions :)
From what I have learned in other sources, the turn looks a lot larger from that video then it actually was. Would a much smaller turn (angle) change any of your conclusions? (I'm suspecting not). How many degrees of turn was actually needed from where they lost power to hit the bridge?
You sad the wind wouldn't have mattered, how accurate is that wind data for different heights above water/ground? While 5-7 knots of wind is light, it would be more then doubled by the speed of the vessel I would think? Does that change anything? Would the bridge and land around it not have likely "shaped" the wind to not be the "normal" direction? Are the cargo containers stacked in a wind-neutral arrangement, or could those catch wind differently enough to create a turning force? Even if we were to assume the wind was straight from the worst angle, how much of a turning motion would that impart vs just pushing the ship sideways without turning her?
Do you think that them not hitting the bridge head on, but from the side mattered? As they have been grounded, would a head-on collision potentially ground then before they reach the bridge pillar(s)? How far up on land would a ship this size and weight get before stopping?
And the bank effect, a large question about that is the second smaller channel on the south side? How do you think that would play into it here?
Also, how much steering capability is left without any propeller wash on such a large vessel? I suspect that the rudder(s) are above the keel of the vessel? I started to question this after a different video by someone also working on a large vessel, although in a different role.
One last question, and IMO the most important one: Lots of talk about "why no tugs". At these speeds, how much can "normal" tugs do? How high would the risks for tugboats be if connected to a ship of this size and speed? I think it's easy to only look at the idea of tugboats saving the day, but would they even have been able to do so without taking massive risks?
No need to answer all of them, but all answers will be appreciated!
I need to call you to reply to all these questions haha
You can DM me and we can chat about it
I saw on other videos that there was electrical problems. The captin should not have been made to leave the port with things not working right.
If you go on a car trip with your family and you need a new tire you wait and get a new tire. By right the captine is legally boxed in by having to work with a ship that was not 100%.
The ship owners or operators are not responsible for the Maryland Transportation Department NOT ensuring that the bridge across a busy port with huge ships was adequately protected from damage by collision / allision. Rebuild costs for the bridge should be for the same standard of bridge NOT full cost of a new superbridge… let the state or Federal Government pay for that.
The question is if the engine was actually in reverse. Engineer Makoi - an expert in his own ship, doesn't think it was started and explains why. The walking propellor theory makes a lot of sense for sure and that with the black smoke looks like a smoking gun. He says that to reverse the engine is not an instantaneouos thing - it is complicated especially after the blackout. At the end of the day, the recorder will tell us.
Only the report will confirm.
10:21 The ebb tide can only be excluded if the tides were normal.
The previous high tide caused flooding on the East coast so you can't just toss the ebb tide.
You mean the previous high water before midnight?
@@MustaphaZehhaf Yes, the previous high tide flooded the Indian River Bridge that was really an inlet to another bridge.
ua-cam.com/video/P45gtBQBgwg/v-deo.html
@@MustaphaZehhaf weird my first reply is gone.
I think the Indian River Bridge was flooded by high tide the night before.
Captain, the propeller effect would not cause that drastic of a turn and a pilot or captain would have stopped the engine if it did. Emergency power is to keep up the hydrolic pressure in the rudder ram as well as power the helm. If they did nothing and the ship was on course with momentum it would have cleared the bridge while they continued corrective actions.
They had another black out after initiating the engine astern.
During the black out, there is no steering gear power
I have seen another informed analysis which disagrees about the generator and engine behaviour, mostly by looking at the smoke and which lights came back on. He says the emergency generator never came on (due to the time delay and non-emergency lights coming on), instead a backup generator started and then later quit. He says the main engine never restarted in reverse or forward… the very strange black smoke indicates that.
For me the severe swing into the bridge was caused by something that was INTENDED to turn the ship quickly, i.e. the steering gear, you say in the video that without hydraulics the rudder will self-centre and not remain in position but if a turn command was made but not actioned due to the power loss then it might have suddenly turned when power came back on.
In any case the massive ship would have continued straight along the channel at 7-8 knots and safely under the bridge if they had just left it alone and restored the power systematically. They couldn’t have done a better job of destroying the bridge if they tried….
This is another theory as well, assuming the rudder order was left to starboard and when the EDG came onload, the rudder turned to STBD.
where is the "black box" ?
recording of ship power and steering system?
With the NTSB
Very well explained.
How much is Chubb on hook for the bridge replacement cost?
Sir, at 10:16 you state that the south east wind was "opposite to the ship's direction and therefore would not slow down the vessel". But south east was also the direction of the ship, therefore the ship was running before the wind, not oppositely.
Are you sure SE wind isn't opposite to SE Heading?
The wind direction is where the wind is coming from not where the wind is going.
@@MustaphaZehhafI am very sorry. I am thinking oppositely. Thank you. But I have another comment coming.
Thanks for the explonation here and as I did say this in my previous comments and most likely you did gather all relevand information the course of the collision was going full astern and that explain also the thick black smoke from the main engine going full astern. That is the moment that is clearly visible on the pictures the movement of the vessel to starboard with this kind of propeller going in the astern position but she had a fixed propeller so the blades where welded to the shaft. My theory therefore was correct and the blame is with the person giving this command from the bridge as the chief engineer don't do that by himself unless he is ordered to do so. Makes a long story short in this case, YES it was a human error by giving the wrong command to the ER / main engine. I'm also pretty sure that if they just give the engine dead slow ahead with little port rudder she would have safely passed the bridge. The anchor on ps did NOT give any effect to the vessel as it did not even touched the bottom and for that we have pictures how the chain was going strait down in the water after the collision. So Mustapha, you and me came to the same conclusion. Now in your next video just show us the course line 140 degrees until the first black-out and what would have happened with the scenario as I descriped it, sure we are on the same line. Sorry for the master if he did give that command full astern knowing he (the vessel) did have a right handed propeller. Told you I'm already an old man 76 but this is something that every master should know and sure in this event use his brain what will happen. He (the master) is to blame as he don't know his ship where he is sailing on. Sorry for the 6 dead road workers but the master should be arrested and look into his experience sailing with ANY vessel this size and what it is doing going astern. Anyway, looking forward to your further investigation, as one master to another, keep it safe.
Just after the engine reversal, they had another black out, so didn't have the time to correct the course by engine ahead.
Thanks for your comment.
@@MustaphaZehhaf it was possible that they changed back to main power from EG as then you have a small little black-out as changing over with the tripper switch. But then again, as fumes where not stopped but only the light did change and came back on and so you need to see on the ER computoer what really happen. But sure this was the case changing back to "normal " power. But look into the course line of 140 and maybe you have a simulator there and can do this with NO ASTERN given.
Excellent video Captain! Talk about a hands-on explanation. Would tugs have helped avoid the collision?
I believe so
thank you for your explantions, I concur with you. one question though, the anchor cable is verticle from the hausse pipe. had the anchor been dropped further back, even if it didnt 'dig in', the cable should be still lying tight and toward the stern. Given the wreckage and damage on the fore deck, I do not believe that the anchor wil have been released post colision. your thoughts please
The depth there is less than 20 m, it they dropped only 2 shackles, then the cable would be up and down
@@MustaphaZehhaf thanks, my thoughts too, which means the anchor had no part to play in the position or placement of the vessel. (where is the Stb Anchor? cant even find it in the high reso pics)