Marine electrician and long time subsriber here. Well done video Chief! This was a great explanation that anyone can follow and understand. I hope the internet algorithm gets this out to all of those who are following the story.
you're taking this guy's advice? last time he was popular on the internet he kept getting angry because people called him out when he kept incorrectly calling the Evergreen the "ever given" lol. It said Evergreen right on it. lolll
5/18/24..A+ on this your 2nd video re: MVDali vs Key Bridge collision. Chief, this video was much more understandable than several other YT reviews of the NTSB (preliminary?) report focusing on the Electrical layout. Much appreciated the time you have taken to pull up pictures of the different equipment 'boxes' & splice-in actual video of the engine room with close-ups of the various 'boxes'. Also you spent much time (editing) showing the chronology of the events as the flow path traveled from 1 box along its circut thru the safety circut overload 'breakers' then continuing along to lower voltage area then to the many needed areas....instantly!! So far several YT commentors all focus on this electrical schematic & emphasize the various flow Paths...but you are the only one who mentions the possible Cause...>like what feeds the big generators< ..# 1,2,3 & 4 which trigger everything that follows. As you say Chief, we all must wait for further info from NTSB...but I think you are on the right track! Thx Chief, 👍⚙️🔩👨🔧
@@YODAINFATSVILLEthe company that ran the Ever Given was (is?) Evergreen (Marine) ... Hence the large writing on the side of the ship. The ship's name (Ever Given) was on the stern (in much smaller writing Hope that helps ...
Chief Makoi, there are two kinds of "engineers" to be found in a ship's engine room. There are those who know which way to rotate a wrench when making repairs, and there are those that understand the physical laws and principles that define a ship's systems and operation. You obviously fit the latter category by your excellent presentation of the Dali's systems and probable failure causes.
That's the difference that having 4 stripes on your uniform makes :) The cadets and oilers/wipers do most of the heavy physical work of turning large wrenches and cleaning up messes.
I'm an old Coast Guardsman, 75, who served on the Bridge but I would have been honored to serve under you. Fair winds and a following sea in your travels. 🌍🚢
As an electrician I can say that the overcurrent protections trip the circuit breakers when there are problems downstream to protect the upstream installation, the exception is the differential protection and the fact that both switches on transformer 1 are disconnected at the same time, this leads me to the idea that the differential protection worked i.e. somewhere in the installation there was an insulation defect that put one of the phases to ground, due to the fact that after the second disconnection the electrician connected transformer 2 makes me think that he suspected an insulation defect on transformer 1
Thank you. When I heard BOTH breakers tripped, I wondered. That function would absolutely be needed if Both transformers were on line and one had a ground fault. (Ex ET radar not a Electricians mate, but that did push my What The button)
Good thinking on this. I'm not familiar with vessels of this size, but electrical systems on ships are required to be fairly fault tolerant for exactly this reason. It is considered to be safer to have a warning of a fault and continue to have an operating ship, rather than an automatic disconnect. In this system there may be a setpoint at which a warning is not sufficient and disconnect is required to prevent catastrophic damage.
@@davidsutton9195 Transformer diff, bus diff, gen diff will all trip instantaneously. No delay, no warning and usually attempts to prevent a catastrophic failure of that component. Over current, under / over frequency, over / under voltage you will have a delay within certain parameters and can be instantaneous outside certain parameters. A differential works by comparing what current is coming in to what current is going out on that piece of equipment. Any "differential" between that and it will trip to limit the fault current and try to save the equipment. And yes, the relays are configured to account for the different voltages and respective currents and or phase shift depending on transformer configuration. When something trips on differential you normally do not ever just reset and re-energize without inspecting the device that just tripped. When a lockout rolls due to a differential, it's usually an oh shit moment. If lucky, it was some unlucky animal that got itself electrocuted and the equipment is usually OK. On land, snakes, raccoons, birds, rats and even iguanas (when I worked in S Florida) are the usual culprits. I'm sure on ships you can get snakes or rats as well. With a three phase delta distribution / feeder, you can have one phase fault to ground and continue to operate with a ground fault warning. But if another phase were to contact ground, now you have a phase to phase fault. But any ground or phase fault within a differential zone of protection, as mentioned above will trip instantaneously.
@@davidsutton9195 I think it's just a matter of procedure here, namely the two transformers TR1 and TR2 I'm sure are identical, so there wouldn't be any problem if during the critical port entry-exit periods both are connected in parallel, and the differential protection of each transformer could disconnect in case of fault the transformer that has problems and the other one remains online. Yes indeed, the differential protection simultaneously triggers both switches on the transformer and the high voltage input and the low voltage one, I have not worked on ships but in factories this is how it works
Yes Chief, I've been waiting for your comments on the NTSB report. Your explanation and diagram are excellent but in the end the preliminary report seems to raise more questions than it answers. I guess we'll have to wait for the final version and hope that the mysteries are solved.
I’m a retired ships pilot. Thank you so much for providing these detailed videos about this issue and shipping in general. There are so many RUclipsrs that only have a cursory knowledge of shipping and really don’t have much experience. It would have been nice to work with you when I was sailing. Keep up the good work!
Could you imagine that losing `propeller walk´ once main engine slows down and finally stops could cause some `compensation effect´ pushing stern to starboard then (opposite to active prop-walk pushing to port for right-handed propeller)? I wonder whether such thing could explain Dali veering to starboard and towards the pillar once the first blackout happened. However, just thinking from physics here, and thus I'm interested in feedback from experienced seafarers & pilots.
I worked for 35 years on large broadcast transmitter plant that had very similar split HV/LV busbars like on that ship (although in our case the HV was 11kV). In my experience, nearly every HV breaker feeding a transformer had intertripping that caused the LV breaker to trip out if the HV breaker tripped. This way, the transformer was completely disconnected from supply - especially backfeed from the LV bus bar which could exacerbate a transformer problem if that was the reason the HV breaker tripped. Thanks for your excellent explanation of the NTSB report - it will be interesting what the final report says. As you note, I find it strange they seem to have been doing maintenance on the only working generator when the inadvertent closure of an exhaust damper caused a blackout. There's a lot to come out yet! Smooth sailing, Chief!
Sal from What's Going on With Shipping did a break down of this, but your chart/diagram makes it much clearer and makes your explanation easier to understand for us landlubbers. 😉 Thanks for the information and video!
your explanation is clear and concise, adding color to the wiring schematic is very helpful, explaining the reverse order of piston firing explained what has been previously fumbled by others, and the system as a whole is less complex than one may have thought, in explanations I have seen so far. this presentation was both informative and educational to the non technician, there is nothing worse than you tubers rushing to get it out first, when they know little of what they are discussing. thank you. carry on and remain calm, as usual !!
Chief Makoi and SteamMan are both notable in that both are actual marine Chief Engineers, serving on similar design and sized ships. To say they "know their stuff" is a massive understatement. They live it every day.
Many thx, I was waiting for YOUR video about the report because you know what you are talking about and for me you are by far the most reliable source of information regarding this kind of thematic! 👍👍👍 Have a good time! 🥰
I've seen walk-throughs of the NTSB report by a couple of other RUclipsrs... the NTSB's over-simplified graphics and RUclipsr explanations injected confusion and raised questions; your graphics and explanations cleared things up very nicely.
Good day Chief. Another excellent video, with your explanation which clears up all the misconceptions which arose from the too over-simplified schematic diagram put up by the NTSB report. I fully concurr with your statements that in normal operation all the bus tie breakers are closed. You have explained everything properly. Rgds, Richard (retired JRCS tech).
His diagram and explanation are a perfect example of good engineering practice. Never put anything in your explanation you don't need to make your point.
Your system diagram is head and shoulders above the NTSB release and makes the systems, and the report for that matter, more understandable to the less experienced viewer. Your coverage shows the difference between those that do, and those that are following along. You and a rare few are doing great work making all things seafaring interesting, enductional, and even fun to know about.
There seem to be serious questions that need to be answered about the competency of the NTSB people who released that report with such a deficient diagram that was incomplete, misleading and inaccurate. If that sort of thing is the basis upon which the NTSB conducts its business and investigations then there seem to be serious problems. Not the least of which being questions about their ability to even understand systems yet alone reach well reasoned and technically sound conclusions.
Thank you Chief, this is the true and correct explanation of the NTSB report, as it is very clear in all details. I worked with 50 Hz generators and the breaker usually trips either because of a current overload, an under/over voltage, or because of an excessive frequency deviation, say below 45 Hertz or above 55 Hertz. The engine governor keeps the frequency in range by intervening on the fuel pump; if - as per your hypothesis - the fuel was tainted, the governor couldn't keep the speed, the frequency dropped, and the breaker tripped. This make sense for the second blackout, when the 6,600 Volt line was killed; the first blackout, very likely, was triggered by an under voltage condition, as the frequency alarm is designed to accept the temporary frequency drop which occur when an heavy load is suddenly applied. Thank you once more! Greetings from the UK, Anthony
Thanks again Chief for your explanation. I would think that the ship did not respond to the rudder and in fact swung to starboard due to the still ebbing tide coming off the Curtis Bay channel which pushed the stern to port. My humble opinion as a long retired master mariner.
Chief MAKOi, yourself and chief `Steam man´ are doing great job here by following up and providing comprehensive explanations & insights as best as can. Each with partly slightly different perspective, but everyone trying to be very objective and focussed on facts - highly appreciated! So carry on , please!
Excellent analytical chronological report on that NTSB electrical schematic & many YT comments. You go to 'what Feeds' the 4 main generators? FUEL. Appreciate all t time you spent grabbing pics of the equipment + engine room video showing these big 'boxes'...very big stuff! Thx again Chief for all your time spent assembling & editing your report to all we viewers. A+👍👍👍
Chief - Thank you for your explanation, I was waiting for this. As a retired engineer who knows nothing about marine system design (but somewhat aircraft and industrial - I'm a mechanical guy) you filled in the blanks I was having to guess at with the NTSB report (not knocking them - I understand they are trying to communicate with all knowledge levels). I see some people talking about operating the system 'split' during critical maneuvering so if you lose half the system the other side keeps all systems functional, more akin to an aircraft layout. Would be interesting to hearing if that is ever done, pro and con, etc. Being retired from industry I also realize how cost enters into decisions many time - sometimes when it should not be a consideration. Enjoy getting your instructional course as you describe everything. Thanks for this effort, much appreciated.
Being one of the `some people´ 😅 (and even using allegory with 4-engine birds like B-747 or A380), let me share that basically my rationale when thinking about going for `split operation´ in confined waters comes from a safety approach; primarily targeting to avoid total loss of electrical power (due to full redundancy) but as fast as can be recovery at least. Reading other comments from chiefs & experienced seafarers, it appears to be common practice on ships to have both HR and LR cross-ties closed (but cutting one transformer path instead). Discussion also brought up `classic´ transformers (i.e. with coil windings) better should be kept online from HV-side (but switched off from LV bus, thus no further load) to have some heating to get rid of moisture plus avoiding strong initiate inrush currents. Keeping them connected to the HV bus would be possible for both scenarios. Generators need frequency synchronisation before switched to a common bus (some analogy from aviation is synchronisation of propeller engines to avoid the wings and fuselage build up oscillations due to the `beating´ frequencies coming from different RPM). Perhaps that syncing is slightly easier with HR cross-tie already connected, although the synchronisation control needs to be done by simple sensing of the frequencies already before generators are connected. For almost all cases, the approach with closed HR and LR cross-ties obviously worked fine so far, and there are also safety measures in place which are working fine if there’s sufficient time for emergency procedures. Such power switching does not happen instantaneously... Now comes probability from such an incident to happen in a location where every second counts… But we also have to wait for all details & findings of the investigation, of course. If there’s another, very central failure which causes the entire system to drown nevertheless, then splitting wouldn’t help either (but further reduce probability at least).
Great video update! Thanks for the analysis. Can you do a video on the status of the crew? I understand they are still aboard the ship and have not gone ashore at any time. How do they get food? How do they get fresh water? Are they getting paid? What has been their interaction with the NTSB? How do you think they are doing? Thanks!
Great video Chief! Your breakdown of what happened was very informative explaining what happened when the ship lost power steering and being underway. Thank you sir and God Bless You and your family! Prayers for the families of those men that lost their lives when the bridge was hit and collapsed.
The first impression I had from the NTSB report was the electrical schematics only showed the generators and transformers. Your schematics made it much easier to understand for this retired mechanical engineer. As you stated, a much more detailed analysis of all of the events on the Dali on that fateful day will be studied in greater detail before the NTSB will issue the final report. Your clarification in this video was greatly appreciated.
Hey Chief I was recommended to your channel I’m finally off my boat with the bandwidth to do It. Great synopsis. The black smoke is a big indicator to me, I’m sure you’ve seen stuck injection pumps in your career. Too many and the generator can’t control its speed and everything else goes wrong. I think the final report will have many more details including bow thruster stop time I have a theory stopping the bow thruster triggered the crew to stop a 3rd generator not discussed so far and that event showed the other 2 online generators unable to adapt to the load change.
Yes; good thought & approach also to look into electrical `load drops´, not only jumps with load increase. We can strongly assume preliminary NTSB report so far only included topics which are waterproof already. But that question wrt “bow thruster stop time” (plus when crew actually started stopping it; as it is supposed being less effective once ship gains speed ahead, thus there’s “plenty of time”) might also be interesting wrt to the direction of Dali’ and this veering to starboard towards the bridge pillar later on. I’d expect bow thruster has been used to make the 180° turn when leaving the pier and moving towards the main channel; possibly still being active when moving straight ahead. With the bow thruster causing water flow to turn the bow (for the 180° turn to port it needs to drag water from port and `pump´ it to starboard), it might be interesting what happens and how once bow thruster engine slows down and stops. Simple assumption is that power will be switched off from the bow thruster motor. Due to inertia of both engine and water flow, the flow will `gradually´ slow down until it stops finally. However, there might kind of `compensation reaction´ such, that water flow might also cause some small push of the bow in opposite direction now, which would be to starboard then. That would fit from timing because if the first blackout would be caused by switching off the bow thruster (while motor and propeller still spinning for a while), it would cause veering momentum which however might only be noticeable later. I could image such kind of `compensation´ also happens wrt `propeller walk´ once main engine slows down (but with much bigger effect there). NTSB prelim report has interesting detail that rudder was amidships (0°) when first blackout occurred - means that `propeller walk´ has not been compensated by rudder at that time. Posted a long comment & question in corresponding Sal’ videos on `What’s going on with shipping?´ wrt that. That’s when I’m spending thoughts wrt the physics involved here - but ask for feedback from any experienced seafarer (PS.: so please bear with me that I’ve hijacked your post for question wrt manoeuvrability, but perhaps somebody jumps on it. I’m really curious not only about the cadence of technical fails but also which effects they’ve caused leading to this overall disaster finally).
Two further questions wrt system components behaviour in case of loss of electrical power - using the opportunity to have 2 chiefs in this conversation here. To me it always interesting to also look into how systems behave when operating conditions are not as expected - especially when lots of inertia is involved. Part I: For a 2-stroke diesel engine, are inlet and outlet valves controlled mechanically or electrically? If mechanically and linked to the rotation of the propeller shaft, that would mean engine sequence would continue `as per normal´, except missing air blowers (I’d assume turbo-charger not active at vessel speed below 10 knots yet - ?) and high-pressure fuel injection. Thus at first moment of power loss there’s less resistance for compressing the air, while last remaining combustions still are done `normally´, but also face less resistance. That could even lead to a slight initial speed-up of the propeller rotation until lack of further combustions. That goes towards the effect of propeller walk. For short time, it might even get bit stronger, but then the increased imbalance of water levels might kick back stronger later on, providing a more pronounced push of stern to port. If valve control is completely done electrically, we would end up in a closed system with a (temperature dependent) compression, which I’d assume acts as kind of `damper´ and resistance to the rotation of the propeller. But also here loss of compression could lead to same effect on propeller spin & walk as per above.
Part II: behaviour of hydraulics of rudder control NSTB prelim report stated rudder amidship (0°) at the time of first loss of electrical power. That leads to question if rudder might face a certain clearance with the loss of pressure from hydraulic pumps. I’d expect for safety reasons, cylinders have control / blocking valves which help to keep pressure and thus rudder position to quite good amount, with liquids being much less compressible compared to air. However, if there’s certain clearance nevertheless, could it be that water levels & pressure caused by `compensation´ of propeller walk might slightly push the rudder towards starboard, thus also contributing a bit to the turn to starboard observed (although I’d expect `compensation effect´ of the prop-walk being main contributor here)?
@@NRZ-3Pi10 Dali has what we call an electronic main engine its designation is ME I have not worked on that type but know it’s electronic fuel injection. I’m not sure any of it matters for the accident as all 2 stroke diesels will immediately shut down on loss of electricity. Now will they turn for a bit before they truly stop? Sometimes and it depends on how fast the ship was going. Every ship and engine is going to have a different speed where that happens
@@steamman9193 Thanks again for sharing these details! Based on this and some more brainstorming, I more and more tend towards the reason why Dali veered to starboard once losing electrical power and main engine is due to the *currents induced in the relatively shallow waters* of Baltimore port by Dali’s *propeller itself* (!). As long as main engine still running, it appears like the propeller walk even seemed to be compensated by these currents, as rudder has been amidships (i.e. not compensating any prop-walk effect). Once main engine gone - which as per your feedback obviously can / will happen in quite short time - those currents will still keep remaining for a bit longer time due to inertia of water; now dominating since also no prop-walk any longer. I did very simple calculation trying to get a grip on the dimensions. For simplicity, let’s take a mass of 100000t (metric tons) which needs to be brought on speed of 8 knots ( ~ 4m/s ). Applying conservation of momentum ( momentum = mass * velocity ), it needs equivalent mass of 100000t at same speed (or less mass but at higher speed then), but in opposite direction. Sounds incredible, but considering water comes along with weight of 1t / m³ (1000t in a cube of 10m x 10m x 10m = 1000m³), it “just” needs 100 * 1000m³ , i.e. 100 of such 10mx10mx10m cubes. Dali has width of ~50m, and can only move along the main channel of Baltimore harbour. Thus I’d expect the amount of water which can be used for propulsion below bottom is quite limited. Means most of the water to be pushed & accelerated by the propeller needs to come from the sides then. For simplicity, let’s split 100 * 1000m³ in (2sides * 50cubes/side) * 1000m³ or (2sides * 2lanes * 25cubes per side&lane) * 1000m³. In other words, all the water needed comes from 2 lanes with width of 20m next to Dali at a length of 250m (which is almost full length of the ship), which will cause currents in the vicinity of Dali. Due to area besides the main channel is relatively shallow, I'd expect strong currents towardss water surface. However, due to rotation of right-handed propeller, there’s also drag / pull of water on starboard, and push-up on port side. So in principle a vertical component pushing Dali’ stern to port, but obviously compensated by propeller walk here. However, once main engine and propeller stops, the flow of tons of water will still continue for bit longer time, with a vertical component pushing stern to port still and thus causing bow moving to starboard (and the pillar) now; assuming the ship turns around its centre of gravity. Sounds reasonable? Would be interesting to know whether the water depth is considered in simulations of harbour situations. Currents of Curtis canal and remaining tidal currents, plus some wind might add on top in unfavourable direction. Feel free to file it under “Aahhh, another landlubber discovering maritime basics” 😅. But as engineer, I prefer to start getting understanding based on such basics first, before right-away going into esoteric stuff or even this conspiracy crap (…) why Dali veered towards the pillar during the blackout. Finally, it’s not by chance electrical engineering (especially for high frequency & micro-waves) uses terms like currents, waves & vortex as there’s lots of analogies to be found in fluid mechanics (but much more tangible there).
A good walkthrough, Eng. The more detailed one line diagram helps immensely by showing the vital bus, its generators, and the emergency bus tie breaker. Also, the normal lineup with the tie breakers shut. That ship’s loads were 480 V with 6600 V for cargo panels and bow thrusters was a big clarification. I share your suspicions about a 480 V fault and a SSDG fuel issue.
Thanks, excellant graphics and explanations. All said in done these "errors" cost 6 men there lives and over a billion dollars of damages. Inadequate crew training, neglect of testing emergency backup systems and lack of maintenance. This shipping company, not the US taxpayers, will be the damages, and paying for a new bridge.
I've seen a couple of good reviews of the NTSB report (including Sal M's), but your version of the electrical diagram made a big difference in clarifying how things work and the sequence of events. Many thanks for providing your experienced view. You can't beat the opinion of an impartial professional who actually does the job. Thanks and best wishes from the UK.
Former Master and DPA /retd) in a small German company here. I've been following you for a while now Chief Makoi, and like many others am sure, I've been waiting for your analysis on the USCG/NTSB report - many many thanks! Of course you are right, without the prop wash, the rudder would've been ineffective! If they see your videos, I wouldn't be surprised if the USCG or NTSB ask you to join them😂
Yes as a ex-chief electrical officer in the British merchant marine many years ago. I sure understand what you are saying in such a competent manner very much like the Chief engineers I sailed with. They understood their craft completely and in one case would only go to the engine room on entering or leaving port when he was legally obliged to. All other times he would call the second engineer and say go and check such and such. This was his ability to hear or feel by the sound or vibration the operation of the main engine and generators. I feel you are the same sort of chief though you will have in the cabin a lot of engine room monitoring gear. Many thanks, Chief Den
Well Done Chief, having watched your videos over the years I have a deep respect for you and your experience as a engineer, and later chief engineer on a variety of cargo ships. You did an excellent job of explaining the report and giving us your observations and thoughts on this accident. Well Done Sir.
As Marine Engineer I appreciate your technical analysis of the NTSB report. But from all indication the The Dali had a competent Engine room crew board
@@ChiefMAKOi ain't seen one that I didn't like. As a heavy truck mechanic for over 30 years it's interesting to see the difference in the equipment. For the most part they are all the same. Same principles I guess you could say. They are all nuts and bolts. Anyway let me know when you are going to treat your team to something different and I will definitely kick in some doh. It's an honor to. There's so many channels to donate to but like anything else some are probably a bit sketchy as to what the money will go towards I have no doubt when I donate to you. Ty for the informative and relevant information I love it. I'm to old to change my path now so it's nice to be able to see what it's all about. Take care of yourself and your crew. On last thing. What is the closest you have been to Canada or have you been here and if so have you ever sailed on the great lakes. Sorry if sailed isn't the correct word. Also you hear stories about how they can be far dangerous then the ocean's. I've heard stories of people who spent their entire lives on the water and say no way not happening. Thanks again and sorry for the long comment. 👍🇨🇦🔧
Judging by all the mainstream comments, for some reason people think that ships can just slam it in to reverse and stop on a dime. Im certainly glad your videos are out there. 👍👍
Great explanation Chief. I’ve watched a few of the other people covering this and they have done a great job but you nailed it on the engineering aspects of the report. Look forward to future comments when the final report comes out.
As an industrial electrical technician for almost 30 years. I appreciate the Chief detailed explanation. I will be awaiting any more videos especially when the final NTSB report is released. I do understand going thru alarms as I have troubleshoot failures on production lines to find the root cause of the line's shutdown. You have to figure out which specific alarm was the cause of the shutdown. You can only figure that out if you have a through understanding on how a particular system operates and how it can fail. Thank you, Chief.
Agreed...there was commentary that this also happened while in port those few days prior to departing. Sounds like its coming down to inexperienced crew. Also, back in the day most "rudders" were called a wash plate because they didn't really function well without the "prop wash" pushing thrusts of water onto it. Our world is changing....not enough theory of operation and history is being given to education and training from my observations. Folks today seem to know very limited information about their jobs and have little references when things go wrong as to how to correct it or, more importantly, just get it done as a temporary fix until legitimate procedures can be restored. I've seen this happen more times than not with todays workers, experts and so forth.
Second this from experience in my field. Keyword - or shall I better call it buzz-word - is `specialisation´, paired with high workload such that it's more important to jump from one task to next rather than also building up more broad-band knowledge...
That is terrifying to me. I was navy operator in the steam plant on aircraft carriers. We had to understand the fundamentals of systems in the plant right down to the basic physics. And while I was a mechanic and thus ran the turbines and pumps and propulsion an generators (turbinenside) I had to understand the electrical and electronics well enough to know how they behaved and why. In our school if you didn't know why you could fail even if you got the short answer correct. I know not all systems and ships were as "big" or complex or redundant as a carrier but tonnage is tonnage. And keeping a ship running and maneuverable is paramount. Maintains safety margins, knowing immeaditae actions, reading the plant quickly and decisively so it can be restored is just necessary. You can't do that if you don't understand that. Specialization might be good for being good at the technical knowledge need for good maintenance but these guys are operators to and need to be proficient in those core knowledge skills and abilites too.
@@zionbrin1 At the end, to me it’s key to have a healthy, balanced mix. On the one hand, specialists being able to really get down to atomic (or even sub-atomic) level are needed to push limits of science & engineering. Same time, you need more `generalist experts´, who can follow the specialists of different fields and especially are able to understand & build the links in between the various disciplines. The more people you have with such broadband skills, the better of course. In case of aircraft carriers and submarines, it’s essential being able to fix things and overcome critical situations quickly with limited crew (and no other help being in around which one could call …). So no surprise to me there’s such selection and training of crew members to achieve resilience; paired with intense emergency `drill exercises´. In principle, same applies for civil maritime crews for same reasons, of course. Wrt industry, I already put my comment above. Like mentioned, it depends on individual attitude and partly on workload. But I also challenge mgmt. levels here; with quite some of them putting more focus on their own career instead of strengthening & building up resilient team (and unfortunately preventing talented people to climb up). To be clear: this comment is not intended as kind of assessing or even judging on Dali’ crew performance here.
Many thanks to you Chief, for this detailed but easy to understand explanation of how this disaster unfolded. I enjoy all of your videos and appreciate learning about life as a seaman. My career was in underground mining where high voltage equipment was in common use. Similar but different to your electrical systems. Safe travels and best regards from Australia.🇦🇺
Watched a few of the other channels try to decipher the report, this is the best explanation yet. Black smoke on a diesel usually indicates an over fueling or rich fuel condition. I guess we will have to wait for the full report. This will take time as there is billions of dollars involved in the cleanup, rebuild, and commercial loss at stake here.
An interesting item is while the heavy smoke was present, according to AIS data the Dali was rapidly decelerating and turning to starboard - and only during the black smoke emission. AIS data is available every 10 seconds. From 1:25:00 when power was lost the first time until the smoke began at 1:26:09 the ship only slowed by 0.2 knots and COG changed to starboard by 1 degree. The ship was drifting. From 1:26:09 when the heavy smoke starts to 1:28:07 shortly before the smoke stopped, the ship slowed by 1.8 knots and COG went to starboard by 14 degrees. The ship was rapidly decelerating and turning. From 1:28:07 to just before impact with the bridge at 1:29:15 the ship only slowed by 0.2 knots and the COG changed to starboard by 2 degrees. The ship was drifting. It sure looks to me like the main propulsion engine was restarted after the first power failure and was running in full reverse for 2 minutes to cause the heavy black smoke and rapid deceleration, and prop walk caused the large starboard COG change which ultimately resulted in impact with the bridge. Nothing else explains the velocity and course change only while the heavy smoke was present.
I think you are right. The report did not talk about the smoke. That smoke looks like #6 fuel to me. I cannot understand how #2 could make that smoke. You are right about doing maintenance on a running system . I think they are using the testimony of the crew. I suspect some are not telling the truth. However, the full report will get to the truth. It may take a while, but they will get the the real causes.
Thank you, Some make assumptions about a situation that isn't fully supported by known facts. Or make statements from a desk that isn't supported by real world experience. Then being argumentive to those who ask questions or point out inconsistent statements made. In contrast you talk TO your audience, using your personal knowledge and experience to support your hypothesis. You do so in order to inform and educate your "crew". Showing leadership while still leaving room for discussion and input.
Thanks Chief between you and Sal, I understand what (not how) happened. Retired USn Interion Communications elect, that was qualified on 600lb. steam plant generator watch standing.
You are the only shipping channel I watch on the regular. You explain everything so simply. And the videos I’ve watched have been informative and though provoking.
thanks so much for your report as I am an apritance electrician in the reestural side I dont know about ship systems and your digram was great to help me understand ships systems and I found your throw Sal's youtube channel
Chief Makoi, I've been a long-time fan and enjoy your videos. Great analysis! at the 12:45 mark there is a brief subtle flash on the top beam of the bridge to the left of the Dali, about 20% of the screen width from the Dali. The lower beam of the bridge has a significant buckle at that point in time directly under that flash suggesting that there may have also been a pre-placed cutting charge on the top beam to facilitate/direct the collapse. I don't know if you or any of your viewers noticed or care to comment--keep up the GREAT work!
Could there have been a worm in the software of these automated systems? There have been reports that the Chinese container cranes in port could have surreptitiously inserted code into shipboard systems (as could numerous other causes), I know you're an engineer, not an IT security expert. But with automated systems, software is involved, probably not air-gapped systems so accessible online especially when in close proximity to appropriate digital transmitters as would be more likely in port than at sea...
Ahh the conspiracy stuff comes flying out. You don't think a million tons ramming a bridge can bring one down all by its lonesome? Look up the Tampa Bay Bridge, Tacoma Narrows and the Minnesota collapse (and the near failure of a bridge down Tennessee way that inspections were being faked on). You just proved there is no over coming the power of human stupidity.
Some considerations from technical perspective wrt collapse of the Key Bridge itself, some `moving lights´; but especially some `flashes´ which can be observed. Quite long comment, targeting to come up with the physics behind. Deleted my earlier comment and replaced with more detailed review now. Time stamps refer to YT video uploaded by `First Coast News’ (Full Video Francis Scott Key bridge ...); I've also uploaded this comment there. This moving light, starting 02m31s coming from right, going to left (until 03m13s) at a level where webcam position suggests is “same height as the main bridge truss”, can simply be either helicopter or airplane - that’s it. Period. Few considerations before digging into the other, individual flashes observed. My view upfront: some of them related to simple electrical shorts, the others most likely due to strong metal bending and ripping caused by forces of the collapse (only). At 0129 EDT am it’s typically dark, except from the lightshow coming from Baltimore harbour; with some top lights of the container cranes on same height as the bridge truss. So easiest explanation for some `flashes´ simply might be lights being hidden before. Possibly also some reflections when the bridge segment starts moving downwards. Plus the smoke from Dali also causing some blurring effect towards left side. Camera sensor might also be more sensitive with sudden changes when lights covered by the truss before get visible. However, yes, when carefully observing and watching the video, this cannot really explain the flashes observed. First glow at 05m39s (012849EDT), then 05m40s (012850EDT), the video shows two flashes, i.e. glowing spots in the middle of the left bridge truss which collapsed and shows serious bending already. Take note all 3 bridge’s flashing signal lights still operating at that time and turned on (especially the one to the right just switched on) - i.e. electricity still present. So easiest explanation could be that we simply can see their cables being damaged and creating short-circuit - which typically ends up with flashes. That’s very obvious for the left bridge truss segment. Assuming cables are running along top side of the truss, that could also explain the flashes observed close to the signal light in the middle of the main truss few moments later at same time 05m40s still. Note this signal light only briefly seemed to light up again but never fully made it and is gone then. At some point we might expect a breaker tripping due to high current. Also lighting on the bridge lanes disappeared on the left and middle truss segment (while still working on the one to the right). 05m42s (012852EDT) is very interesting since the main truss starts to break towards its right pillar, with flashes both on top side of the truss but also its lower, inner bow. I’d be bit surprised and ask why the cable for signal lights on the top should move down to the inner bow there. Could be; flashes would have same root cause then although I’d be surprised that no electrical fuses already cut off power there. Much more important, extreme bending can be observed, due to large amount of the truss already accelerating towards the water due to its weight and force of gravity (plus possibly some forced due to the impact when Dali hit the pillar), while the part close to the pillar still fixed to it. 05m43s (012853EDT) the middle of main truss has already reached water level - i.e. 50m lower. Same time lights went out on the right truss, possibly another short circuit in case there’s still been voltage present in the cables. So far some the flashes could have been explained by shorts in the electrical cables. First “white” flash, follow by more yellowish / orange one in case some of the isolation gets burned & vapourized. But I don’t think that’s all, so let’s get to some more nasty stuff - physics. To start with something easy: there’s no question that cutoff grinding creates a lot of sparks flying around, right? Obviously steel doesn’t really like this treatment. Glowing sparks suggest quite some energy involved, too. Main truss of the Key bridge had clear height of more than 50m / 167ft. Top level of the main truss could be up to 100m / 333ft. The bridge starts to collapse and gravitation kicks in. Very simple rule says with acceleration of 10m/s² , after 1 second speed could be as fast as 10m/s = 36km/h already; and main bridge truss already dropped by 10m then, too. In reality it can additionally be influenced due to some mechanical forces (either slowed down or accelerated further). Energy goes with velocity squared; v² - ooopps. At 05m42s; i.e. only 2 seconds after the initial flash described for left truss segment, the inner bow moved down by approx. 20m / 66ft, with a speed of already 2s * 10m/s² = 20m/s = 72km/h then. Tons of steel crashing down and heavily pulling at those points where one can observe the flashing in the truss. Again, 05m43s the middle of main truss has already reached water level - i.e. 50m lower. If you simply drop a stone from 100m height (let’s neglect some potential friction when moving in air), it reaches water surface after 4.47s , at a speed of 44.7m/s = 161km/h - oouuch. 05m44s (012854EDT) the last angle-steel strap rips-off finally, with another remarkable flash. I wonder if that’s electrical cable still, or whether this is different effect now. Bending and finally ripping-off creates much heat, and there’s very strong forces involved here to bend these angle steel straps for sure. So I’d say this flash might be caused by the forces & energies made visible in the darkness of the night when the electromagnetic bindings between the atoms are ripped off, possibly also ionising air due to the heat involved. Feel free to call me `mad dog´; but when has this made visible in such a way before? But I have something even much more spectacular for you: 05m47s; especially 05m49s (012859EDT) - check the collapse of the truss directly above the right pillar of main bridge section. It starts unsuspicious, however exactly when lower bow of the truss finally crashes on the pillar. You can observe very pronounced orange glowing then, first on the right, but later especially to the left. Could partly come from port lights, camera effects etc. However, this segment crashes down with upper parts from height of 70m minimum, then `rubs´ along the pillars (remember, 50m clear height minimum), creating lots of friction, bending and heat again. Yes, may look like blowing of charges or some explosion. But partly takes too long (expected to be short single flash); and I’m missing the smoke that would typically come along with that (especially when the flashes are in orange). It's all physics triggered due to MS Dali crashed into the pillar; without any other additional “influence”. By accident, the roadworks at night and quick reaction of Baltimore pilots office and MDTA officers prevented human disaster of even higher magnitude. Those 6 road-workers who have lost their lives - may their souls rest in peace. My sincere condolences to their families.
I've seen several explanations of the NTSB report. I thought they were good and helped me to understand what is known about the failure. With that said, your video provided better clarity. Thank You.
Wow. Chief Makoi. Thanks for the explanation. Scary scenario for all crews to watch out for. Perhaps a day tank to gravity feed the generators needs to be added. 15 minutes of extra gravity fed fuel may have kept the generators running perhaps depending on design.
Very interesting and detailed as usual. Who knows they may eventually come up with a plausible solution. That was an awful lot of black smoke. Doesn't sound like they have addressed that yet. Surely that must be coming from main engine. Not generators. Like trying to start up an old tractor or truck. Churn over and pump out smoke before they start. Whatever the real reason, the cost will be through the roof. And any insurance company will be playing pass the parcel. Trying to limit pay out.
Chief Makoi, you are a true asset to your profession. You are but a handful on the Internet that can describe complex systems in an understandable and respectful and timely manner. Glad you're "aboard" this platform.
8:02 - That is the emergency generator coming on. The navigation lights and emergency lighting for the walkways along the side of the ship came on, but the big spotlight on the front didn't dome back on. It comes back on later just before impact when they were using the 3rd generator and the second transformer.
@@ChiefMAKOi We had High Pressure Sodium when I started back in the 80s, then it shifted to Metal Halide and at the last LED. The HPS and MH had various rapid re-strike systems if they were considered emergency (every 3rd light in a facility). Some just had an aux Halogen bulb that came on until the HPS got going puling enough current to open the relay. Mercury are the worst of them for power use, HPS then MH and the LEDs of course very efficient (costly but far fewer failures of the bulbs or ballasts)
Master chief, Great new information on main generator issues. There was no mention why the ship turned towards the bridge peir. The rudder was amidship. So was ship going straight ahead or was it still turning at time of main engine failure and then continued to turn into peir? Why did ship not drift in a straight course when engine failed? There are 2 issues with this accident 1.Why engine failure? 2. Why ship turned into peir? Thank for best video on report yet! Cheers Warren
Excellent analysis Chief Makoi, especially the elaboration of the simplified NTSB circuit diagram. My conjecture - immediately after the crash - was a fuel related one. Possibly excessive paraffins, the wax of which will clog the low-micron sintered filters, which cannot easily be removed in the auto filter self cleaning operation. The suspected and alleged blackouts, when alongside, led me up that path. Search me, how could they even think of closing the dampers of a running generator? Isn’t this the domain of a senior engineer? (I’ve had this - choking of filters - happen to me twice, when we were, crazily, changing over filters while maneuvering, until we went to an older and different Diesel Oil source. The wax in the paraffins of Diesel Oil will choke the filters quickly. The same wax in the paraffins in Heavy Fuel Oil will not choke the low micron sintered filters as the HFO is heated to around +130 deg C. The melting point of these paraffins is from 45 to 60 deg C). The only way to clean these (choked) sintered filters is either to ‘steam’ them or use a light flame, the steaming being preferable. But the NTSB Preliminary Report is inclined towards malfunction of HR1 and LR1, normally very reliable, especially if they are Terasaki. If fuel related, loss of speed of the Generators 3 and 4, would have triggered the ‘Low Voltage’ or ‘Low Frequency’ alarms in the Generator Starting Circuit, which would have tripped DGR3 and DGR4, not HR1or LR1. Even as they were tripping (DGR3 / 4), Generators 1 or 2, or both, would have started automatically and come on load, as they would have been on ‘Auto Standby’. The total load on the switchboard would have lessened, as the ‘Non Essentials’ - including Reefer Containers and Domestic Systems - would have tripped. So, even one Generator would have been capable of taking the ship’s load, as the Bow Thruster would have tripped and would need to be reset before starting. (Although, I expect that they would have switched off the BT even before the blackouts near the Bridge - worth examining when did they switch off the BT). Noting the heavy black smoke after the black out, it could be from one or both the ‘Standby’ Generators starting up. In the ‘comments’ section, I read one comment that ‘Low Insulation’ of the HV Switchboard could have tripped this breaker HR 1. In this kind of an HV setup, it will be reasonable to expect heavy protection in the form of alarms, indication on meters, auto-tripping of minor breakers etc. in case of ‘Low Insulation’. If an HV Breaker were to trip due to Low Insulation, would it not have caused a heavy spark at some place or the other? Unless there was a problem with the breaker HR 1 / LR 1 itself. But why would the malfunction of one of them trip the other? Only one breaker should trip, not both. The irony is that, whatever took place, if it had taken place a few minutes later, it would have resulted in either grounding or drifting, no more. I do not want to speculate further, as the investigation is still on. But, we have not seen the end of it…..AR
Again I shall say " Good job Chief!" In our environment of misinformation and arm chair experts it is very refreshing to have an easy to comprehend, non biased explanation of the possible series of events...I am by no means a knowledgable seafarer but I was able to follow easily your explanations of the accident. It will be interesting to hopefully hear what exactly failed and what important lessons have been learned from this tragic event. Wish you and your mates continued smooth sailing.
Thanks, Chief. Take care and fair winds I thought the black smoke was the engine doing a reset exhaust expulsion as they attempted a restart. Clearing out the pipes as they say.
I have Noe experience, however am curious if not fascinated as to what could have caused this catastrophe. You explanation Chief was so clear and easy to follow. Thank you for the visuals as it was so helpful for a novice like me.
I've managed to get a farm tractor engine running backwards. Climbing on a pile of silage with too low throttle, the engine stalled and the tractor started rolling backwards and the engine came back to life. With gear still on and clutch not pressed, I accidentally did a hill start in reverse with a forward gear on. Now the forward gear moved the tractor backwards! After a few moments of fun to verify the gears were really the wrong way and the engine must be running backwards too, I restarted the tractor and all was right again. Probably water pumps and lubrication work better with the engine running the intended way! :^)
While you can start a vehicle engine in reverse (diesel) it has nothing to do with the Dali engine, it runs in reverse deliberately. Pumps are all totally independent and nothing to do with engine rotation. .
It often never a singular event that cause an airplane accident, but a serious of events that lead to the catastrophe. I appreciate you bringing this down to the level for us laypeople to understand. I suspect that we might find mechanical, along with operational faults, led to this happening… all at the worst moment it could happen.
Thank you so much. More technical than other sites which is valuable for your audience. Yep lots of questions. I was in engineer on a Navy ship so am very interested in the procedures for loss of SSDG or other loss of power casualties. Keep up the good work and your dissection of the reports is most interesting and valuable.
I wish you end up in an education position somewhere in your carrier. I had a few really good teachers I am always thankful, and you could be this teacher for a lot lot of people.
I’ve sat through more than a few electrical schematic discussions with graphics and detailed explanations for aircraft and your presentation was excellent. Yet I expected no less of an effort from you because you are always spot on in clarity. Thanks again for an insight into your profession. You do yourself and fellow Engineers proud.
Marine electrician and long time subsriber here. Well done video Chief! This was a great explanation that anyone can follow and understand. I hope the internet algorithm gets this out to all of those who are following the story.
Much appreciated
you're taking this guy's advice? last time he was popular on the internet he kept getting angry because people called him out when he kept incorrectly calling the Evergreen the "ever given" lol. It said Evergreen right on it. lolll
5/18/24..A+ on this your 2nd video re: MVDali vs Key Bridge collision. Chief, this video was much more understandable than several other YT reviews of the NTSB (preliminary?) report focusing on the Electrical layout. Much appreciated the time you have taken to pull up pictures of the different equipment 'boxes' & splice-in actual video of the engine room with close-ups of the various 'boxes'. Also you spent much time (editing) showing the chronology of the events as the flow path traveled from 1 box along its circut thru the safety circut overload 'breakers' then continuing along to lower voltage area then to the many needed areas....instantly!!
So far several YT commentors all focus on this electrical schematic & emphasize the various flow Paths...but you are the only one who mentions the possible Cause...>like what feeds the big generators< ..# 1,2,3 & 4 which trigger everything that follows.
As you say Chief, we all must wait for further info from NTSB...but I think you are on the right track! Thx Chief, 👍⚙️🔩👨🔧
@@YODAINFATSVILLEthe company that ran the Ever Given was (is?) Evergreen (Marine) ... Hence the large writing on the side of the ship. The ship's name (Ever Given) was on the stern (in much smaller writing
Hope that helps ...
@@YODAINFATSVILLE seriously???
Chief Makoi, there are two kinds of "engineers" to be found in a ship's engine room. There are those who know which way to rotate a wrench when making repairs, and there are those that understand the physical laws and principles that define a ship's systems and operation. You obviously fit the latter category by your excellent presentation of the Dali's systems and probable failure causes.
Right tighty lefty loosy 😂
That's the difference that having 4 stripes on your uniform makes :) The cadets and oilers/wipers do most of the heavy physical work of turning large wrenches and cleaning up messes.
Top man chief so clear and precise
I'm an old Coast Guardsman, 75, who served on the Bridge but I would have been honored to serve under you. Fair winds and a following sea in your travels. 🌍🚢
As an electrician I can say that the overcurrent protections trip the circuit breakers when there are problems downstream to protect the upstream installation, the exception is the differential protection and the fact that both switches on transformer 1 are disconnected at the same time, this leads me to the idea that the differential protection worked i.e. somewhere in the installation there was an insulation defect that put one of the phases to ground, due to the fact that after the second disconnection the electrician connected transformer 2 makes me think that he suspected an insulation defect on transformer 1
That's a very likely possibility.
Thank you. When I heard BOTH breakers tripped, I wondered. That function would absolutely be needed if Both transformers were on line and one had a ground fault. (Ex ET radar not a Electricians mate, but that did push my What The button)
Good thinking on this. I'm not familiar with vessels of this size, but electrical systems on ships are required to be fairly fault tolerant for exactly this reason. It is considered to be safer to have a warning of a fault and continue to have an operating ship, rather than an automatic disconnect. In this system there may be a setpoint at which a warning is not sufficient and disconnect is required to prevent catastrophic damage.
@@davidsutton9195 Transformer diff, bus diff, gen diff will all trip instantaneously. No delay, no warning and usually attempts to prevent a catastrophic failure of that component. Over current, under / over frequency, over / under voltage you will have a delay within certain parameters and can be instantaneous outside certain parameters. A differential works by comparing what current is coming in to what current is going out on that piece of equipment. Any "differential" between that and it will trip to limit the fault current and try to save the equipment. And yes, the relays are configured to account for the different voltages and respective currents and or phase shift depending on transformer configuration. When something trips on differential you normally do not ever just reset and re-energize without inspecting the device that just tripped. When a lockout rolls due to a differential, it's usually an oh shit moment. If lucky, it was some unlucky animal that got itself electrocuted and the equipment is usually OK. On land, snakes, raccoons, birds, rats and even iguanas (when I worked in S Florida) are the usual culprits. I'm sure on ships you can get snakes or rats as well.
With a three phase delta distribution / feeder, you can have one phase fault to ground and continue to operate with a ground fault warning. But if another phase were to contact ground, now you have a phase to phase fault. But any ground or phase fault within a differential zone of protection, as mentioned above will trip instantaneously.
@@davidsutton9195 I think it's just a matter of procedure here, namely the two transformers TR1 and TR2 I'm sure are identical, so there wouldn't be any problem if during the critical port entry-exit periods both are connected in parallel, and the differential protection of each transformer could disconnect in case of fault the transformer that has problems and the other one remains online. Yes indeed, the differential protection simultaneously triggers both switches on the transformer and the high voltage input and the low voltage one, I have not worked on ships but in factories this is how it works
Chief, thank you for your input on this report. You stated matters so clear, and your charts made it easy to follow. Thank you!
I appreciate that!
Yes Chief, I've been waiting for your comments on the NTSB report. Your explanation and diagram are excellent but in the end the preliminary report seems to raise more questions than it answers. I guess we'll have to wait for the final version and hope that the mysteries are solved.
I’m a retired ships pilot. Thank you so much for providing these detailed videos about this issue and shipping in general. There are so many RUclipsrs that only have a cursory knowledge of shipping and really don’t have much experience. It would have been nice to work with you when I was sailing. Keep up the good work!
Could you imagine that losing `propeller walk´ once main engine slows down and finally stops could cause some `compensation effect´ pushing stern to starboard then (opposite to active prop-walk pushing to port for right-handed propeller)? I wonder whether such thing could explain Dali veering to starboard and towards the pillar once the first blackout happened. However, just thinking from physics here, and thus I'm interested in feedback from experienced seafarers & pilots.
So nice to hear someone say "from my experience" when talking about a subject.
To the Chief & commenters THANK YOU
I worked for 35 years on large broadcast transmitter plant that had very similar split HV/LV busbars like on that ship (although in our case the HV was 11kV). In my experience, nearly every HV breaker feeding a transformer had intertripping that caused the LV breaker to trip out if the HV breaker tripped. This way, the transformer was completely disconnected from supply - especially backfeed from the LV bus bar which could exacerbate a transformer problem if that was the reason the HV breaker tripped. Thanks for your excellent explanation of the NTSB report - it will be interesting what the final report says. As you note, I find it strange they seem to have been doing maintenance on the only working generator when the inadvertent closure of an exhaust damper caused a blackout. There's a lot to come out yet! Smooth sailing, Chief!
Sal from What's Going on With Shipping did a break down of this, but your chart/diagram makes it much clearer and makes your explanation easier to understand for us landlubbers. 😉 Thanks for the information and video!
My pleasure! 😊
your explanation is clear and concise, adding color to the wiring schematic is very helpful, explaining the reverse order of piston firing explained what has been previously fumbled by others, and the system as a whole is less complex than one may have thought, in explanations I have seen so far. this presentation was both informative and educational to the non technician, there is nothing worse than you tubers rushing to get it out first, when they know little of what they are discussing. thank you. carry on and remain calm, as usual !!
I try my best. Thanks 😊
Chief Makoi and SteamMan are both notable in that both are actual marine Chief Engineers, serving on similar design and sized ships.
To say they "know their stuff" is a massive understatement. They live it every day.
Many thx, I was waiting for YOUR video about the report because you know what you are talking about and for me you are by far the most reliable source of information regarding this kind of thematic! 👍👍👍
Have a good time! 🥰
You are very welcome.
I've seen walk-throughs of the NTSB report by a couple of other RUclipsrs... the NTSB's over-simplified graphics and RUclipsr explanations injected confusion and raised questions; your graphics and explanations cleared things up very nicely.
THIS is why it's not worth the brain space to have little patience waiting on the Chief.
Good day Chief. Another excellent video, with your explanation which clears up all the misconceptions which arose from the too over-simplified schematic diagram put up by the NTSB report. I fully concurr with your statements that in normal operation all the bus tie breakers are closed. You have explained everything properly. Rgds, Richard (retired JRCS tech).
Thanks Richard.
2:45 A frakking beautiful work of art. I love info-graphics and yours is sublime for its content and simplicity.
Glad you enjoy it!
@@ChiefMAKOi I did indeed enjoy your video. Keep up the good work. What did you use to create the infographic?
Chief Makoi, you rule!!! As Electrical Engineer I enjoyed the crystal clear - though simplified - way you explained the entire timeline of events!
His diagram and explanation are a perfect example of good engineering practice. Never put anything in your explanation you don't need to make your point.
General Curtis LeMay had a saying I'm fond of: "I find it hard to tell the difference between the unfortunate, and the incompetent".
Incompetents don't listen and ignore repeated warnings (Stockton for example).
Your system diagram is head and shoulders above the NTSB release and makes the systems, and the report for that matter, more understandable to the less experienced viewer. Your coverage shows the difference between those that do, and those that are following along. You and a rare few are doing great work making all things seafaring interesting, enductional, and even fun to know about.
There seem to be serious questions that need to be answered about the competency of the NTSB people who released that report with such a deficient diagram that was incomplete, misleading and inaccurate.
If that sort of thing is the basis upon which the NTSB conducts its business and investigations then there seem to be serious problems. Not the least of which being questions about their ability to even understand systems yet alone reach well reasoned and technically sound conclusions.
I believe the first diagram is the original. It's called schematic diagram.
Thank you Chief, this is the true and correct explanation of the NTSB report, as it is very clear in all details.
I worked with 50 Hz generators and the breaker usually trips either because of a current overload, an under/over voltage, or because of an excessive frequency deviation, say below 45 Hertz or above 55 Hertz. The engine governor keeps the frequency in range by intervening on the fuel pump; if - as per your hypothesis - the fuel was tainted, the governor couldn't keep the speed, the frequency dropped, and the breaker tripped. This make sense for the second blackout, when the 6,600 Volt line was killed; the first blackout, very likely, was triggered by an under voltage condition, as the frequency alarm is designed to accept the temporary frequency drop which occur when an heavy load is suddenly applied.
Thank you once more!
Greetings from the UK,
Anthony
Well xplain. I use to be a tester of gen - set tester. 😊
Excellent explanation of the NTSB report! Thanks Chief!
Thanks again Chief for your explanation. I would think that the ship did not respond to the rudder and in fact swung to starboard due to the still ebbing tide coming off the Curtis Bay channel which pushed the stern to port. My humble opinion as a long retired master mariner.
I actually defer to Master Mariners when it comes to these topics. 😁 That's a good explanation.
Pure logic reporting (if somewhat above my previous knowledge), but put in a very clear chronological order, accompanied by a clear, precise diagram..
Excellent report Chief. I was waiting to hear your take and you did not disappoint.
Chief MAKOi, yourself and chief `Steam man´ are doing great job here by following up and providing comprehensive explanations & insights as best as can. Each with partly slightly different perspective, but everyone trying to be very objective and focussed on facts - highly appreciated! So carry on , please!
Thanks Sal! 😊
Excellent analytical chronological report on that NTSB electrical schematic & many YT comments. You go to 'what Feeds' the 4 main generators? FUEL. Appreciate all t time you spent grabbing pics of the equipment + engine room video showing these big 'boxes'...very big stuff!
Thx again Chief for all your time spent assembling & editing your report to all we viewers. A+👍👍👍
Thanks for being knowledgable and explaining so a layman can undwestand
My pleasure
Chief - Thank you for your explanation, I was waiting for this. As a retired engineer who knows nothing about marine system design (but somewhat aircraft and industrial - I'm a mechanical guy) you filled in the blanks I was having to guess at with the NTSB report (not knocking them - I understand they are trying to communicate with all knowledge levels). I see some people talking about operating the system 'split' during critical maneuvering so if you lose half the system the other side keeps all systems functional, more akin to an aircraft layout. Would be interesting to hearing if that is ever done, pro and con, etc. Being retired from industry I also realize how cost enters into decisions many time - sometimes when it should not be a consideration. Enjoy getting your instructional course as you describe everything. Thanks for this effort, much appreciated.
Being one of the `some people´ 😅 (and even using allegory with 4-engine birds like B-747 or A380), let me share that basically my rationale when thinking about going for `split operation´ in confined waters comes from a safety approach; primarily targeting to avoid total loss of electrical power (due to full redundancy) but as fast as can be recovery at least.
Reading other comments from chiefs & experienced seafarers, it appears to be common practice on ships to have both HR and LR cross-ties closed (but cutting one transformer path instead).
Discussion also brought up `classic´ transformers (i.e. with coil windings) better should be kept online from HV-side (but switched off from LV bus, thus no further load) to have some heating to get rid of moisture plus avoiding strong initiate inrush currents. Keeping them connected to the HV bus would be possible for both scenarios.
Generators need frequency synchronisation before switched to a common bus (some analogy from aviation is synchronisation of propeller engines to avoid the wings and fuselage build up oscillations due to the `beating´ frequencies coming from different RPM). Perhaps that syncing is slightly easier with HR cross-tie already connected, although the synchronisation control needs to be done by simple sensing of the frequencies already before generators are connected.
For almost all cases, the approach with closed HR and LR cross-ties obviously worked fine so far, and there are also safety measures in place which are working fine if there’s sufficient time for emergency procedures. Such power switching does not happen instantaneously... Now comes probability from such an incident to happen in a location where every second counts…
But we also have to wait for all details & findings of the investigation, of course. If there’s another, very central failure which causes the entire system to drown nevertheless, then splitting wouldn’t help either (but further reduce probability at least).
Great video update!
Thanks for the analysis.
Can you do a video on the status of the crew? I understand they are still aboard the ship and have not gone ashore at any time. How do they get food? How do they get fresh water? Are they getting paid? What has been their interaction with the NTSB? How do you think they are doing?
Thanks!
Great video Chief! Your breakdown of what happened was very informative explaining what happened when the ship lost power steering and being underway. Thank you sir and God Bless You and your family! Prayers for the families of those men that lost their lives when the bridge was hit and collapsed.
Always appreciate your analysis, Chief. Very clear as usual.
Much appreciated.
Your words are very confident.. I like to listen to your words.. cheers from Vietnam
Thanks and welcome
Thanks and welcome
The first impression I had from the NTSB report was the electrical schematics only showed the generators and transformers. Your schematics made it much easier to understand for this retired mechanical engineer. As you stated, a much more detailed analysis of all of the events on the Dali on that fateful day will be studied in greater detail before the NTSB will issue the final report. Your clarification in this video was greatly appreciated.
Hey Chief I was recommended to your channel I’m finally off my boat with the bandwidth to do
It. Great synopsis. The black smoke is a big indicator to me, I’m sure you’ve seen stuck injection pumps in your career. Too many and the generator can’t control its speed and everything else goes wrong. I think the final report will have many more details including bow thruster stop time I have a theory stopping the bow thruster triggered the crew to stop a 3rd generator not discussed so far and that event showed the other 2 online generators unable to adapt to the load change.
Yes; good thought & approach also to look into electrical `load drops´, not only jumps with load increase. We can strongly assume preliminary NTSB report so far only included topics which are waterproof already.
But that question wrt “bow thruster stop time” (plus when crew actually started stopping it; as it is supposed being less effective once ship gains speed ahead, thus there’s “plenty of time”) might also be interesting wrt to the direction of Dali’ and this veering to starboard towards the bridge pillar later on. I’d expect bow thruster has been used to make the 180° turn when leaving the pier and moving towards the main channel; possibly still being active when moving straight ahead. With the bow thruster causing water flow to turn the bow (for the 180° turn to port it needs to drag water from port and `pump´ it to starboard), it might be interesting what happens and how once bow thruster engine slows down and stops. Simple assumption is that power will be switched off from the bow thruster motor. Due to inertia of both engine and water flow, the flow will `gradually´ slow down until it stops finally. However, there might kind of `compensation reaction´ such, that water flow might also cause some small push of the bow in opposite direction now, which would be to starboard then. That would fit from timing because if the first blackout would be caused by switching off the bow thruster (while motor and propeller still spinning for a while), it would cause veering momentum which however might only be noticeable later.
I could image such kind of `compensation´ also happens wrt `propeller walk´ once main engine slows down (but with much bigger effect there). NTSB prelim report has interesting detail that rudder was amidships (0°) when first blackout occurred - means that `propeller walk´ has not been compensated by rudder at that time. Posted a long comment & question in corresponding Sal’ videos on `What’s going on with shipping?´ wrt that.
That’s when I’m spending thoughts wrt the physics involved here - but ask for feedback from any experienced seafarer (PS.: so please bear with me that I’ve hijacked your post for question wrt manoeuvrability, but perhaps somebody jumps on it. I’m really curious not only about the cadence of technical fails but also which effects they’ve caused leading to this overall disaster finally).
Two further questions wrt system components behaviour in case of loss of electrical power - using the opportunity to have 2 chiefs in this conversation here. To me it always interesting to also look into how systems behave when operating conditions are not as expected - especially when lots of inertia is involved.
Part I: For a 2-stroke diesel engine, are inlet and outlet valves controlled mechanically or electrically?
If mechanically and linked to the rotation of the propeller shaft, that would mean engine sequence would continue `as per normal´, except missing air blowers (I’d assume turbo-charger not active at vessel speed below 10 knots yet - ?) and high-pressure fuel injection. Thus at first moment of power loss there’s less resistance for compressing the air, while last remaining combustions still are done `normally´, but also face less resistance. That could even lead to a slight initial speed-up of the propeller rotation until lack of further combustions. That goes towards the effect of propeller walk. For short time, it might even get bit stronger, but then the increased imbalance of water levels might kick back stronger later on, providing a more pronounced push of stern to port.
If valve control is completely done electrically, we would end up in a closed system with a (temperature dependent) compression, which I’d assume acts as kind of `damper´ and resistance to the rotation of the propeller. But also here loss of compression could lead to same effect on propeller spin & walk as per above.
Part II: behaviour of hydraulics of rudder control
NSTB prelim report stated rudder amidship (0°) at the time of first loss of electrical power. That leads to question if rudder might face a certain clearance with the loss of pressure from hydraulic pumps. I’d expect for safety reasons, cylinders have control / blocking valves which help to keep pressure and thus rudder position to quite good amount, with liquids being much less compressible compared to air. However, if there’s certain clearance nevertheless, could it be that water levels & pressure caused by `compensation´ of propeller walk might slightly push the rudder towards starboard, thus also contributing a bit to the turn to starboard observed (although I’d expect `compensation effect´ of the prop-walk being main contributor here)?
@@NRZ-3Pi10 Dali has what we call an electronic main engine its designation is ME I have not worked on that type but know it’s electronic fuel injection. I’m not sure any of it matters for the accident as all 2 stroke diesels will immediately shut down on loss of electricity. Now will they turn for a bit before they truly stop? Sometimes and it depends on how fast the ship was going. Every ship and engine is going to have a different speed where that happens
@@steamman9193 Thanks again for sharing these details!
Based on this and some more brainstorming, I more and more tend towards the reason why Dali veered to starboard once losing electrical power and main engine is due to the *currents induced in the relatively shallow waters* of Baltimore port by Dali’s *propeller itself* (!). As long as main engine still running, it appears like the propeller walk even seemed to be compensated by these currents, as rudder has been amidships (i.e. not compensating any prop-walk effect). Once main engine gone - which as per your feedback obviously can / will happen in quite short time - those currents will still keep remaining for a bit longer time due to inertia of water; now dominating since also no prop-walk any longer.
I did very simple calculation trying to get a grip on the dimensions. For simplicity, let’s take a mass of 100000t (metric tons) which needs to be brought on speed of 8 knots ( ~ 4m/s ). Applying conservation of momentum ( momentum = mass * velocity ), it needs equivalent mass of 100000t at same speed (or less mass but at higher speed then), but in opposite direction. Sounds incredible, but considering water comes along with weight of 1t / m³ (1000t in a cube of 10m x 10m x 10m = 1000m³), it “just” needs 100 * 1000m³ , i.e. 100 of such 10mx10mx10m cubes. Dali has width of ~50m, and can only move along the main channel of Baltimore harbour. Thus I’d expect the amount of water which can be used for propulsion below bottom is quite limited. Means most of the water to be pushed & accelerated by the propeller needs to come from the sides then. For simplicity, let’s split 100 * 1000m³ in (2sides * 50cubes/side) * 1000m³ or (2sides * 2lanes * 25cubes per side&lane) * 1000m³. In other words, all the water needed comes from 2 lanes with width of 20m next to Dali at a length of 250m (which is almost full length of the ship), which will cause currents in the vicinity of Dali. Due to area besides the main channel is relatively shallow, I'd expect strong currents towardss water surface. However, due to rotation of right-handed propeller, there’s also drag / pull of water on starboard, and push-up on port side. So in principle a vertical component pushing Dali’ stern to port, but obviously compensated by propeller walk here. However, once main engine and propeller stops, the flow of tons of water will still continue for bit longer time, with a vertical component pushing stern to port still and thus causing bow moving to starboard (and the pillar) now; assuming the ship turns around its centre of gravity.
Sounds reasonable?
Would be interesting to know whether the water depth is considered in simulations of harbour situations.
Currents of Curtis canal and remaining tidal currents, plus some wind might add on top in unfavourable direction.
Feel free to file it under “Aahhh, another landlubber discovering maritime basics” 😅.
But as engineer, I prefer to start getting understanding based on such basics first, before right-away going into esoteric stuff or even this conspiracy crap (…) why Dali veered towards the pillar during the blackout.
Finally, it’s not by chance electrical engineering (especially for high frequency & micro-waves) uses terms like currents, waves & vortex as there’s lots of analogies to be found in fluid mechanics (but much more tangible there).
A good walkthrough, Eng. The more detailed one line diagram helps immensely by showing the vital bus, its generators, and the emergency bus tie breaker. Also, the normal lineup with the tie breakers shut. That ship’s loads were 480 V with 6600 V for cargo panels and bow thrusters was a big clarification. I share your suspicions about a 480 V fault and a SSDG fuel issue.
Thanks, excellant graphics and explanations. All said in done these "errors" cost 6 men there lives and over a billion dollars of damages. Inadequate crew training, neglect of testing emergency backup systems and lack of maintenance. This shipping company, not the US taxpayers, will be the damages, and paying for a new bridge.
Thanks, Chief! I love your electrical diagram, it makes sense of a long and wordy report.
Glad it was helpful!
Thankyou Chief. You are a real expert who can give an unbiased viewpoint on these big ships. Backed by experience and your job as a Chief Engineer.
Retired industrial electrician. Thank you for the explanations. Good to see you, Chief.
I've seen a couple of good reviews of the NTSB report (including Sal M's), but your version of the electrical diagram made a big difference in clarifying how things work and the sequence of events. Many thanks for providing your experienced view. You can't beat the opinion of an impartial professional who actually does the job. Thanks and best wishes from the UK.
yes as i am an apritnace ele on house hold 220 and 110 uthe digram made more since since I dont know ships ele systems
Excellent summary! Take care...
Former Master and DPA /retd) in a small German company here. I've been following you for a while now Chief Makoi, and like many others am sure, I've been waiting for your analysis on the USCG/NTSB report - many many thanks! Of course you are right, without the prop wash, the rudder would've been ineffective! If they see your videos, I wouldn't be surprised if the USCG or NTSB ask you to join them😂
Omg, sir, I'm so thrilled to finally see your take on this!
Hope you enjoyed it!
Chief, thanks for clearing the air about this event. Lots of armchair Captains and Engineers just got their little theories shot down.
Yes as a ex-chief electrical officer in the British merchant marine many years ago. I sure understand what you are saying in such a competent manner very much like the Chief engineers I sailed with.
They understood their craft completely and in one case would only go to the engine room on entering or leaving port when he was legally obliged to.
All other times he would call the second engineer and say go and check such and such.
This was his ability to hear or feel by the sound or vibration the operation of the main engine and generators.
I feel you are the same sort of chief though you will have in the cabin a lot of engine room monitoring gear.
Many thanks, Chief Den
Well Done Chief, having watched your videos over the years I have a deep respect for you and your experience as a engineer, and later chief engineer on a variety of cargo ships. You did an excellent job of explaining the report and giving us your observations and thoughts on this accident.
Well Done Sir.
As Marine Engineer I appreciate your technical analysis of the NTSB report.
But from all indication the The Dali had a competent Engine room crew board
Another comprehensive excellent video Chief!
Hey Chief it's great to get your Saturday videos. It's a great start to the weekend 👍🇨🇦
Glad you like them!
@@ChiefMAKOi ain't seen one that I didn't like. As a heavy truck mechanic for over 30 years it's interesting to see the difference in the equipment. For the most part they are all the same. Same principles I guess you could say. They are all nuts and bolts. Anyway let me know when you are going to treat your team to something different and I will definitely kick in some doh. It's an honor to. There's so many channels to donate to but like anything else some are probably a bit sketchy as to what the money will go towards I have no doubt when I donate to you. Ty for the informative and relevant information I love it. I'm to old to change my path now so it's nice to be able to see what it's all about. Take care of yourself and your crew. On last thing. What is the closest you have been to Canada or have you been here and if so have you ever sailed on the great lakes. Sorry if sailed isn't the correct word. Also you hear stories about how they can be far dangerous then the ocean's. I've heard stories of people who spent their entire lives on the water and say no way not happening. Thanks again and sorry for the long comment. 👍🇨🇦🔧
I have learnt a lot from this elaborate analysis. Thank you Chief!!
Judging by all the mainstream comments, for some reason people think that ships can just slam it in to reverse and stop on a dime. Im certainly glad your videos are out there. 👍👍
Great explanation Chief. I’ve watched a few of the other people covering this and they have done a great job but you nailed it on the engineering aspects of the report. Look forward to future comments when the final report comes out.
As an industrial electrical technician for almost 30 years. I appreciate the Chief detailed explanation. I will be awaiting any more videos especially when the final NTSB report is released. I do understand going thru alarms as I have troubleshoot failures on production lines to find the root cause of the line's shutdown. You have to figure out which specific alarm was the cause of the shutdown. You can only figure that out if you have a through understanding on how a particular system operates and how it can fail. Thank you, Chief.
Agreed...there was commentary that this also happened while in port those few days prior to departing. Sounds like its coming down to inexperienced crew.
Also, back in the day most "rudders" were called a wash plate because they didn't really function well without the "prop wash" pushing thrusts of water onto it.
Our world is changing....not enough theory of operation and history is being given to education and training from my observations. Folks today seem to know very limited information about their jobs and have little references when things go wrong as to how to correct it or, more importantly, just get it done as a temporary fix until legitimate procedures can be restored. I've seen this happen more times than not with todays workers, experts and so forth.
Second this from experience in my field. Keyword - or shall I better call it buzz-word - is `specialisation´, paired with high workload such that it's more important to jump from one task to next rather than also building up more broad-band knowledge...
That is terrifying to me. I was navy operator in the steam plant on aircraft carriers. We had to understand the fundamentals of systems in the plant right down to the basic physics. And while I was a mechanic and thus ran the turbines and pumps and propulsion an generators (turbinenside) I had to understand the electrical and electronics well enough to know how they behaved and why. In our school if you didn't know why you could fail even if you got the short answer correct. I know not all systems and ships were as "big" or complex or redundant as a carrier but tonnage is tonnage. And keeping a ship running and maneuverable is paramount. Maintains safety margins, knowing immeaditae actions, reading the plant quickly and decisively so it can be restored is just necessary. You can't do that if you don't understand that. Specialization might be good for being good at the technical knowledge need for good maintenance but these guys are operators to and need to be proficient in those core knowledge skills and abilites too.
@@zionbrin1 At the end, to me it’s key to have a healthy, balanced mix. On the one hand, specialists being able to really get down to atomic (or even sub-atomic) level are needed to push limits of science & engineering. Same time, you need more `generalist experts´, who can follow the specialists of different fields and especially are able to understand & build the links in between the various disciplines. The more people you have with such broadband skills, the better of course.
In case of aircraft carriers and submarines, it’s essential being able to fix things and overcome critical situations quickly with limited crew (and no other help being in around which one could call …). So no surprise to me there’s such selection and training of crew members to achieve resilience; paired with intense emergency `drill exercises´. In principle, same applies for civil maritime crews for same reasons, of course. Wrt industry, I already put my comment above. Like mentioned, it depends on individual attitude and partly on workload. But I also challenge mgmt. levels here; with quite some of them putting more focus on their own career instead of strengthening & building up resilient team (and unfortunately preventing talented people to climb up). To be clear: this comment is not intended as kind of assessing or even judging on Dali’ crew performance here.
Thanks for the wonderful explanation that a non-technical person like me could understand.
Many thanks to you Chief, for this detailed but easy to understand explanation of how this disaster unfolded.
I enjoy all of your videos and appreciate learning about life as a seaman. My career was in underground mining where high voltage equipment was in common use. Similar but different to your electrical systems.
Safe travels and best regards from Australia.🇦🇺
chief eng. in a small factory, excellent video, nice to hear a report from someone who knows what they are talking about
Watched a few of the other channels try to decipher the report, this is the best explanation yet. Black smoke on a diesel usually indicates an over fueling or rich fuel condition. I guess we will have to wait for the full report. This will take time as there is billions of dollars involved in the cleanup, rebuild, and commercial loss at stake here.
An interesting item is while the heavy smoke was present, according to AIS data the Dali was rapidly decelerating and turning to starboard - and only during the black smoke emission. AIS data is available every 10 seconds.
From 1:25:00 when power was lost the first time until the smoke began at 1:26:09 the ship only slowed by 0.2 knots and COG changed to starboard by 1 degree. The ship was drifting.
From 1:26:09 when the heavy smoke starts to 1:28:07 shortly before the smoke stopped, the ship slowed by 1.8 knots and COG went to starboard by 14 degrees. The ship was rapidly decelerating and turning.
From 1:28:07 to just before impact with the bridge at 1:29:15 the ship only slowed by 0.2 knots and the COG changed to starboard by 2 degrees. The ship was drifting.
It sure looks to me like the main propulsion engine was restarted after the first power failure and was running in full reverse for 2 minutes to cause the heavy black smoke and rapid deceleration, and prop walk caused the large starboard COG change which ultimately resulted in impact with the bridge. Nothing else explains the velocity and course change only while the heavy smoke was present.
I appreciate the attention you put into this and clarifying the report.
Your hand drawn diagrams were great with their clarity and giving immediate understanding to me. A nice breakdown by you. Thanks.
I think you are right. The report did not talk about the smoke. That smoke looks like #6 fuel to me. I cannot understand how #2 could make that smoke.
You are right about doing maintenance on a running system . I think they are using the testimony of the crew. I suspect some are not telling the truth. However, the full report will get to the truth. It may take a while, but they will get the the real causes.
Thank you, Some make assumptions about a situation that isn't fully supported by known facts. Or make statements from a desk that isn't supported by real world experience. Then being argumentive to those who ask questions or point out inconsistent statements made. In contrast you talk TO your audience, using your personal knowledge and experience to support your hypothesis. You do so in order to inform and educate your "crew". Showing leadership while still leaving room for discussion and input.
Thanks Chief. Another great video as always. I:m sure they will be sorting this out for quite a while and I look forward to your insights.
Thank you! This was very clear, and I appreciate you just stating the facts and staying on stuff you are an expert in.
A simple and understandable explanation of the system. Thank you Chief.
Thanks Chief between you and Sal, I understand what (not how) happened. Retired USn Interion Communications elect, that was qualified on 600lb. steam plant generator watch standing.
Thank you Chief! Great explanation !!!
Hey up mate your drawing and words is the first time this report has made some sense, thank you very much
Glad it helped
Not only you comment and ability to specify things, are rite , but clear as the day. Whatever others say. ,-)
You are the only shipping channel I watch on the regular. You explain everything so simply. And the videos I’ve watched have been informative and though provoking.
Excellent, clear, concise, and illuminating. Bravo!
Thank you Chief for another timely update and analysis.
Thank you for the detailed report and bringing it down to street smart levels of knowledge. Learned a lot.
Glad it was helpful!
Best video out here Chief, as retired ch/eng i have great pleasure to follow you
An excellent presentation and analysis of the NTSB report. I like the fact that Chief will not speculate.
thanks so much for your report as I am an apritance electrician in the reestural side I dont know about ship systems and your digram was great to help me understand ships systems and I found your throw Sal's youtube channel
Chief Makoi, I've been a long-time fan and enjoy your videos. Great analysis! at the 12:45 mark there is a brief subtle flash on the top beam of the bridge to the left of the Dali, about 20% of the screen width from the Dali. The lower beam of the bridge has a significant buckle at that point in time directly under that flash suggesting that there may have also been a pre-placed cutting charge on the top beam to facilitate/direct the collapse. I don't know if you or any of your viewers noticed or care to comment--keep up the GREAT work!
Could there have been a worm in the software of these automated systems? There have been reports that the Chinese container cranes in port could have surreptitiously inserted code into shipboard systems (as could numerous other causes), I know you're an engineer, not an IT security expert. But with automated systems, software is involved, probably not air-gapped systems so accessible online especially when in close proximity to appropriate digital transmitters as would be more likely in port than at sea...
Ahh the conspiracy stuff comes flying out. You don't think a million tons ramming a bridge can bring one down all by its lonesome? Look up the Tampa Bay Bridge, Tacoma Narrows and the Minnesota collapse (and the near failure of a bridge down Tennessee way that inspections were being faked on). You just proved there is no over coming the power of human stupidity.
Some considerations from technical perspective wrt collapse of the Key Bridge itself, some `moving lights´; but especially some `flashes´ which can be observed. Quite long comment, targeting to come up with the physics behind. Deleted my earlier comment and replaced with more detailed review now. Time stamps refer to YT video uploaded by `First Coast News’ (Full Video Francis Scott Key bridge ...); I've also uploaded this comment there.
This moving light, starting 02m31s coming from right, going to left (until 03m13s) at a level where webcam position suggests is “same height as the main bridge truss”, can simply be either helicopter or airplane - that’s it. Period.
Few considerations before digging into the other, individual flashes observed. My view upfront: some of them related to simple electrical shorts, the others most likely due to strong metal bending and ripping caused by forces of the collapse (only).
At 0129 EDT am it’s typically dark, except from the lightshow coming from Baltimore harbour; with some top lights of the container cranes on same height as the bridge truss. So easiest explanation for some `flashes´ simply might be lights being hidden before. Possibly also some reflections when the bridge segment starts moving downwards. Plus the smoke from Dali also causing some blurring effect towards left side. Camera sensor might also be more sensitive with sudden changes when lights covered by the truss before get visible.
However, yes, when carefully observing and watching the video, this cannot really explain the flashes observed.
First glow at 05m39s (012849EDT), then 05m40s (012850EDT), the video shows two flashes, i.e. glowing spots in the middle of the left bridge truss which collapsed and shows serious bending already. Take note all 3 bridge’s flashing signal lights still operating at that time and turned on (especially the one to the right just switched on) - i.e. electricity still present. So easiest explanation could be that we simply can see their cables being damaged and creating short-circuit - which typically ends up with flashes. That’s very obvious for the left bridge truss segment. Assuming cables are running along top side of the truss, that could also explain the flashes observed close to the signal light in the middle of the main truss few moments later at same time 05m40s still. Note this signal light only briefly seemed to light up again but never fully made it and is gone then. At some point we might expect a breaker tripping due to high current. Also lighting on the bridge lanes disappeared on the left and middle truss segment (while still working on the one to the right).
05m42s (012852EDT) is very interesting since the main truss starts to break towards its right pillar, with flashes both on top side of the truss but also its lower, inner bow. I’d be bit surprised and ask why the cable for signal lights on the top should move down to the inner bow there. Could be; flashes would have same root cause then although I’d be surprised that no electrical fuses already cut off power there.
Much more important, extreme bending can be observed, due to large amount of the truss already accelerating towards the water due to its weight and force of gravity (plus possibly some forced due to the impact when Dali hit the pillar), while the part close to the pillar still fixed to it.
05m43s (012853EDT) the middle of main truss has already reached water level - i.e. 50m lower. Same time lights went out on the right truss, possibly another short circuit in case there’s still been voltage present in the cables.
So far some the flashes could have been explained by shorts in the electrical cables. First “white” flash, follow by more yellowish / orange one in case some of the isolation gets burned & vapourized.
But I don’t think that’s all, so let’s get to some more nasty stuff - physics. To start with something easy: there’s no question that cutoff grinding creates a lot of sparks flying around, right? Obviously steel doesn’t really like this treatment. Glowing sparks suggest quite some energy involved, too.
Main truss of the Key bridge had clear height of more than 50m / 167ft. Top level of the main truss could be up to 100m / 333ft. The bridge starts to collapse and gravitation kicks in. Very simple rule says with acceleration of 10m/s² , after 1 second speed could be as fast as 10m/s = 36km/h already; and main bridge truss already dropped by 10m then, too. In reality it can additionally be influenced due to some mechanical forces (either slowed down or accelerated further). Energy goes with velocity squared; v² - ooopps. At 05m42s; i.e. only 2 seconds after the initial flash described for left truss segment, the inner bow moved down by approx. 20m / 66ft, with a speed of already 2s * 10m/s² = 20m/s = 72km/h then. Tons of steel crashing down and heavily pulling at those points where one can observe the flashing in the truss. Again, 05m43s the middle of main truss has already reached water level - i.e. 50m lower. If you simply drop a stone from 100m height (let’s neglect some potential friction when moving in air), it reaches water surface after 4.47s , at a speed of 44.7m/s = 161km/h - oouuch.
05m44s (012854EDT) the last angle-steel strap rips-off finally, with another remarkable flash. I wonder if that’s electrical cable still, or whether this is different effect now.
Bending and finally ripping-off creates much heat, and there’s very strong forces involved here to bend these angle steel straps for sure. So I’d say this flash might be caused by the forces & energies made visible in the darkness of the night when the electromagnetic bindings between the atoms are ripped off, possibly also ionising air due to the heat involved. Feel free to call me `mad dog´; but when has this made visible in such a way before?
But I have something even much more spectacular for you:
05m47s; especially 05m49s (012859EDT) - check the collapse of the truss directly above the right pillar of main bridge section. It starts unsuspicious, however exactly when lower bow of the truss finally crashes on the pillar. You can observe very pronounced orange glowing then, first on the right, but later especially to the left. Could partly come from port lights, camera effects etc. However, this segment crashes down with upper parts from height of 70m minimum, then `rubs´ along the pillars (remember, 50m clear height minimum), creating lots of friction, bending and heat again.
Yes, may look like blowing of charges or some explosion. But partly takes too long (expected to be short single flash); and I’m missing the smoke that would typically come along with that (especially when the flashes are in orange).
It's all physics triggered due to MS Dali crashed into the pillar; without any other additional “influence”.
By accident, the roadworks at night and quick reaction of Baltimore pilots office and MDTA officers prevented human disaster of even higher magnitude.
Those 6 road-workers who have lost their lives - may their souls rest in peace. My sincere condolences to their families.
I've seen several explanations of the NTSB report. I thought they were good and helped me to understand what is known about the failure. With that said, your video provided better clarity. Thank You.
Thank you Chief Makoi - for your professionalism and dedication to the maritime industry!
Wow. Chief Makoi. Thanks for the explanation. Scary scenario for all crews to watch out for. Perhaps a day tank to gravity feed the generators needs to be added. 15 minutes of extra gravity fed fuel may have kept the generators running perhaps depending on design.
Very interesting and detailed as usual. Who knows they may eventually come up with a plausible solution. That was an awful lot of black smoke. Doesn't sound like they have addressed that yet. Surely that must be coming from main engine. Not generators. Like trying to start up an old tractor or truck. Churn over and pump out smoke before they start. Whatever the real reason, the cost will be through the roof. And any insurance company will be playing pass the parcel. Trying to limit pay out.
Thanks much. Clarified everything. A standard multiple genset 100% redundancy configuration.
Thank you Chief for lending your extensive expertise to analyze the situation. Excellent and insightful!
Chief Makoi, you are a true asset to your profession. You are but a handful on the Internet that can describe complex systems in an understandable and respectful and timely manner. Glad you're "aboard" this platform.
Thanks Chief. Your plain language translation of the report is appreciated.
You're welcome. 😊
Thanks Chief! Another good one! 👍
8:02 - That is the emergency generator coming on. The navigation lights and emergency lighting for the walkways along the side of the ship came on, but the big spotlight on the front didn't dome back on. It comes back on later just before impact when they were using the 3rd generator and the second transformer.
That's usually a mercury lamp at the front. It takes a while to fully illuminate.
@@ChiefMAKOi We had High Pressure Sodium when I started back in the 80s, then it shifted to Metal Halide and at the last LED. The HPS and MH had various rapid re-strike systems if they were considered emergency (every 3rd light in a facility). Some just had an aux Halogen bulb that came on until the HPS got going puling enough current to open the relay. Mercury are the worst of them for power use, HPS then MH and the LEDs of course very efficient (costly but far fewer failures of the bulbs or ballasts)
Your explanation is very clear and makes sense to me.
Master chief, Great new information on main generator issues.
There was no mention why the ship turned towards the bridge peir. The rudder was amidship. So was ship going straight ahead or was it still turning at time of main engine failure and then continued to turn into peir?
Why did ship not drift in a straight course when engine failed?
There are 2 issues with this accident
1.Why engine failure?
2. Why ship turned into peir?
Thank for best video on report yet!
Cheers Warren
You are top notch with your knowledge.
Excellent presentation, Chief. I'm a retired hospital maintenance mechanic and really enjoy following and appreciating your knowledge.
Excellent analysis Chief Makoi, especially the elaboration of the simplified NTSB circuit diagram.
My conjecture - immediately after the crash - was a fuel related one. Possibly excessive paraffins, the wax of which will clog the low-micron sintered filters, which cannot easily be removed in the auto filter self cleaning operation.
The suspected and alleged blackouts, when alongside, led me up that path. Search me, how could they even think of closing the dampers of a running generator? Isn’t this the domain of a senior engineer?
(I’ve had this - choking of filters - happen to me twice, when we were, crazily, changing over filters while maneuvering, until we went to an older and different Diesel Oil source. The wax in the paraffins of Diesel Oil will choke the filters quickly. The same wax in the paraffins in Heavy Fuel Oil will not choke the low micron sintered filters as the HFO is heated to around +130 deg C. The melting point of these paraffins is from 45 to 60 deg C).
The only way to clean these (choked) sintered filters is either to ‘steam’ them or use a light flame, the steaming being preferable.
But the NTSB Preliminary Report is inclined towards malfunction of HR1 and LR1, normally very reliable, especially if they are Terasaki.
If fuel related, loss of speed of the Generators 3 and 4, would have triggered the ‘Low Voltage’ or ‘Low Frequency’ alarms in the Generator Starting Circuit, which would have tripped DGR3 and DGR4, not HR1or LR1.
Even as they were tripping (DGR3 / 4), Generators 1 or 2, or both, would have started automatically and come on load, as they would have been on ‘Auto Standby’.
The total load on the switchboard would have lessened, as the ‘Non Essentials’ - including Reefer Containers and Domestic Systems - would have tripped.
So, even one Generator would have been capable of taking the ship’s load, as the Bow Thruster would have tripped and would need to be reset before starting. (Although, I expect that they would have switched off the BT even before the blackouts near the Bridge - worth examining when did they switch off the BT).
Noting the heavy black smoke after the black out, it could be from one or both the ‘Standby’ Generators starting up.
In the ‘comments’ section, I read one comment that ‘Low Insulation’ of the HV Switchboard could have tripped this breaker HR 1. In this kind of an HV setup, it will be reasonable to expect heavy protection in the form of alarms, indication on meters, auto-tripping of minor breakers etc. in case of ‘Low Insulation’. If an HV Breaker were to trip due to Low Insulation, would it not have caused a heavy spark at some place or the other?
Unless there was a problem with the breaker HR 1 / LR 1 itself.
But why would the malfunction of one of them trip the other? Only one breaker should trip, not both.
The irony is that, whatever took place, if it had taken place a few minutes later, it would have resulted in either grounding or drifting, no more.
I do not want to speculate further, as the investigation is still on. But, we have not seen the end of it…..AR
Again I shall say " Good job Chief!" In our environment of misinformation and arm chair experts it is very refreshing to have an easy to comprehend, non biased explanation of the possible series of events...I am by no means a knowledgable seafarer but I was able to follow easily your explanations of the accident. It will be interesting to hopefully hear what exactly failed and what important lessons have been learned from this tragic event. Wish you and your mates continued smooth sailing.
Thanks, Chief. Take care and fair winds
I thought the black smoke was the engine doing a reset exhaust expulsion as they attempted a restart. Clearing out the pipes as they say.
I have Noe experience, however am curious if not fascinated as to what could have caused this catastrophe. You explanation Chief was so clear and easy to follow. Thank you for the visuals as it was so helpful for a novice like me.
I've managed to get a farm tractor engine running backwards. Climbing on a pile of silage with too low throttle, the engine stalled and the tractor started rolling backwards and the engine came back to life. With gear still on and clutch not pressed, I accidentally did a hill start in reverse with a forward gear on. Now the forward gear moved the tractor backwards! After a few moments of fun to verify the gears were really the wrong way and the engine must be running backwards too, I restarted the tractor and all was right again. Probably water pumps and lubrication work better with the engine running the intended way! :^)
While you can start a vehicle engine in reverse (diesel) it has nothing to do with the Dali engine, it runs in reverse deliberately. Pumps are all totally independent and nothing to do with engine rotation. .
It often never a singular event that cause an airplane accident, but a serious of events that lead to the catastrophe. I appreciate you bringing this down to the level for us laypeople to understand. I suspect that we might find mechanical, along with operational faults, led to this happening… all at the worst moment it could happen.
Thank you so much. More technical than other sites which is valuable for your audience. Yep lots of questions. I was in engineer on a Navy ship so am very interested in the procedures for loss of SSDG or other loss of power casualties. Keep up the good work and your dissection of the reports is most interesting and valuable.
I wish you end up in an education position somewhere in your carrier. I had a few really good teachers I am always thankful, and you could be this teacher for a lot lot of people.
I believe Chief Makoi has said he teaches on a Simulator at times and he has released video of working towards a training certificate.
Thanks Chief! Great job as always.
I’ve sat through more than a few electrical schematic discussions with graphics and detailed explanations for aircraft and your presentation was excellent. Yet I expected no less of an effort from you because you are always spot on in clarity. Thanks again for an insight into your profession. You do yourself and fellow Engineers proud.