Baltimore Bridge Crash: Risk Management Questions

There are contradictory reports on some key facts regarding the container ship MV Dali destroying Baltimore’s Francis Scott Key Bridge. For instance, the Wall Street Journal quoted an officer of the saying they did not drop anchors, while a shipping expert reported on YouTube that a helicopter had taken and circulated an image of port anchor being deployed but he was not sure about the starboard. Similarly, the BBC reported that the state governor said the vessel was going very quickly, when other commentators have said the reverse (and with a pilot from the port aboard to direct the ship, speeding would seem unlikely).

Nevertheless, even with a less than full picture of what happened, we might be able to pose some productive questions now.

One of the tacit assumptions in much of the coverage is that this event was a Black Swan, or more colloquially, an extreme case of Shit Happens. However, that perspective can divert attention from the notion that there was operational and/or safety corners-cutting that made an event like this too likely given the (heretofore hidden) risks being taken. Naked Capitalism readers, having higher expectations for what passes for our betters, instead took this as yet another sign that we are not a serious country.

The very short version of what happened, as you can track in some of the narrated videos, is that the ship lost power when very close to the bridge, appeared to get it back briefly (which belching of smoke) but looked to be out of control and soon swung out of its channel and into the bridge pier”

Some of the issues:

Why did the power fail? The ship is normally powered by a diesel engine. When the lights came back on and the ship belched smoke, that may have been a restart of the engine. An exclusive Wall Street Journal story says investigators are looking at dirty fuel as a cause. Recall the vessel has passed regular inspection with only minor problems cited. But if this ship got engine-busting bad fuel, why aren’t there other cases?

Why was there no backup capable of very quickly restoring navigation? Again we don’t have a clear picture yet, but the big belch of smoke suggests the crew either tried to restart the engine or perhaps an auxiliary diesel engine. But that sort of process has to take time when there is never enough time in an emergency. It appears there was no battery backup. This is something to watch for as more blow-by-blow reconstructions emerge.

From BBC:

The National Association for Pilot Profession has provided some more details on the ship that crashed into the Baltimore bridge.

The association says the ship lost full power, with no lights, no electronics and no engine propulsion, making it essentially a “dead ship” within 20 to 30 seconds.

The group says lights came back on in the ship thanks to an emergency generator, but that doesn’t give the engine power. Video shows lights flicker back on briefly before the vessel hits the bridge.

Black smoke that billowed from the ship around this time was likely an emergency diesel generator kicking in, the pilot group says

From reader scott s. in comments (emphasis added):

First off, my professional background is US Navy marine engineering, not commercial….

Ships like this use a slow-speed direct coupled diesel that does a max of 90 rpm or so, designed entirely for fuel efficiency. The diesel is remotely controlled via a local control panel. AFAIK typically intended for unmanned operation, though I don’t know if a watchstander is required for entering/leaving port. I assume the local control panel and individual cylinder controls are battery-backed for loss of power…

Ship’s service AC power would be via separate diesel generator with emergency diesel or battery as backup. Certainly the steering motor has normal and emergency power source. In USN practice we use AC motor-driven redundant hydraulic pumps. We have the ability to hand pump the hydraulics (and also set the direction of travel manually) but it’s slow. Actually there is also a big nut on a screw thread alongside the ram and a monster wrench that can be used in last resort to force the rudders into position.

All the control circuitry (helm to rudder and EOT to engine) should be battery-backed.

Did the pilot have any control over the ship after the power failure? The Wall Street Journal says not:

A harbor pilot and assistant reported power issues and a loss of propulsion before the crash, according to a Coast Guard briefing report viewed by The Wall Street Journal.

“The vessel went dead, no steering power and no electronics,” said an officer aboard the ship Tuesday. “One of the engines coughed and then stopped. The smell of burned fuel was everywhere in the engine room and it was pitch black.”

With everything dark and presumably communications within the ship impaired (and this source apparently in the engine room), a single source could have some details wrong. Note that the shipping expert above points out in the video above that if the power had come back sufficiently to regain control of navigation, and the ship had tried to “back off” which I take to mean go into reverse to cut the speed, that would result in the ship careening and so would not have prevented, and could even have helped cause, the crash.

This video overlaps with the one above but has good detail on what the ship’s crew might have done with when the power went out:

scott s. also explained why dropping the anchor wouldn’t/didn’t prevent the disaster:

It was mentioned they did drop an anchor which is also standard naval practice. But just putting an anchor “underfoot” doesn’t provide much holding power. You need to veer chain so the mass of chain works against motion.

Why weren’t tugs used to escort ships, or at least big honker potentially bridge-destroying ships, past the bridge? The news stories say that in the Baltimore harbor, tugs normally only help vessels get in and out of berths. I will have to recheck with Lambert, who has spoken often with a tugboat operator in New York City’s harbor, but the impression I have second-hand is that the New York City tugboats do a fair bit of escorting in the harbor.

The reason this might not be an unreasonable question give the lack of past disasters is that the riskiness of ships going in and out of harbors has likely increased. One has to assume that average sizes have increased, and perhaps also the number of ships going in and out of a port in any year. If you watch the first video above, it looks as if the Dali had barely gotten out of its channel when it hit the pier. If so, that would indicate the margin for error with a pretty big vessel was not that large.

Of course, we know the answer is “because cost”. But if you view tugs as insurance, it now looks as if even many many many years of tugboat assistance would still come in cheaper than the cost of the loss of the harbor during bridge clean-up, the cost of diverting land traffic, and the expense of rebuilding the bridge.

Lambert also notes, and I have not confirmed, that the original proposal was for a tunnel under the harbor, but a bridge was cheaper. That now looks like another false economy.

Was the bridge design or construction deficient? From reader Glenn Olson, in comments:

I’m amazed at how few seconds it took for the bridge to collapse into the water and how many pieces it broke into. As an engineer I’m at a loss to understand the tradeoffs that were made in the design such that loss of one support resulted in so many shear points and total loss of the center span. It’s almost like it was made of glass and shattered at the first impact. Steel designs should not do that.

Reader bob opined that it’s just not possible to design a bridge to withstand this kind of impact. Perhaps that is correct, but Alexander Mercouris regularly claims that bridges are seriously over-built. I am not sure what the analogous terms are in the bridge world, but buildings are designed to handle compression load, wind load on each face of the building (and for eccentric designs like Citicorp Center, rotation load) and again for skyscrapers in New York City, the impact of small aircraft.

But it appears handling impact, such as not collapsing catastrophically, was not a design consideration here. For instance, the bridge appear to have not “dolphins” as in protective underwater structures to take the impact of a ship collision. From Maritime Executive:

Wednesday’s disastrous bridge collapse in Baltimore brought to mind lessons learned in 1980, when the freighter Summit Venture struck and destroyed half of Tampa’s Sunshine Skyway bridge. 35 people died in that disaster, prompting a decade-long rethink of highway bridge design. The Skyway Bridge was rebuilt with a fortress of protective concrete dolphins – but it is unclear whether Baltimore’s Francis Scott Key Bridge was updated to meet a similar standard before it was hit by the boxship Dali on Wednesday morning.

Baltimore’s Key Bridge opened in 1977, three years before the Skyway Bridge disaster (and two years after a similar casualty in Tasmania). Based on visual evidence, the Key Bridge had one small dolphin on each side of the central span’s piers, intended either for scour protection or for defending against allisions. When the container ship Dali approached early Wednesday morning, the vessel appeared to pass by the dolphin and strike the pier directly with her starboard bow.

“Maybe [the dolphin] would stop a ferry or something like that,” consulting engineer Donald Dusenberry told the New York Times. “Not a massive, oceangoing cargo ship.”

Tampa-area attorney Steven Yerrid was involved in the response to the Skyway Bridge disaster in 1980, and he told local media that when he saw the fendering system on the Key Bridge, it looked all too familiar. “I felt not only shock, but extreme sadness, because I knew other people had to unnecessarily lose their lives to learn a lesson that was taught 44 years ago,” Yarrid told Tampa’s Fox 13.

The Skyway Bridge’s lessons were written down and codified by AASHTO, America’s highway standards body, in 1991….

For many engineers, the fact that a landmark structure like the Key Bridge could still be felled by marine traffic is a call to action. “As a matter of principle, when there is a bridge pier in a shipping channel we should expect the bridge to be strong enough to withstand impact or to be protected from impact,” structural engineer Shankar Nair told the Baltimore Banner.

Mind you, the dolphin question is separate from the one raised by Glenn, which is even more germane given the lack of ship-protections like dolphins. Shouldn’t the design and construction provided for enough structural integrity so that a severe hit to a pier would result in only a partial bridge collapse?

Right now, we have more questions than answers. And the questions above may not be the best formulated. But it’s important to keep key issues front and center to understand why this happened and what to do to prevent its recurrence.

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  1. flora

    Thanks for this post.
    Per part of your comment: “…the notion that there was operational and/or safety corners-cutting that made an event like this too likely given the (heretofore hidden) risks being taken.”

    I’m going with this explanation until I’m shown hard evidence of something else.
    See also: Boeing doors, aka because Markets. (aka neoliberal economics.) / my 2 cents.

    adding about the governor’s comments and Gen Flynn comments and others: I understand the political pr reasons for trying to look like one knows what’s happening immediately, but in areas outside one’s expertise coming out with baffle-gab, especially alarmist-sounding baffle-gab – ship too fast, national security response, etc – it’s much much better to say “we are waiting for the maritime and other experts to determine what exactly happened here.” Anything else sounds either childish or political to me, emotionalism instead of steady reason. / my 2 cents.

    1. mrsyk

      Thanks from me as well. I too am going with the corner cutting theory. And thanks for the insurance analogy on tugboats. That cleared a thought logjam. The “victim” profile of this tragedy blows my mind. I can’t help but speculate a massive bailout in the insurance sector or PE is in the making.

      even odds the bridge doesn’t get rebuilt.

  2. dandyandy

    UK Engineer here. My background is in design of civil and structural engineering structures as well as port protection structures.
    To us engineers, to see such a great looking bridge collapse, is a day of sadness.

    The very first thing that surprised me when I watched the videos was that the ship was even allowed to get this close to the principal column set (the main span has two sets of columns with four individual columns in each of the two sets). As it happens, it seems to me that the ship’s bow cut into one of the four columns inside the set, and destroyed it in the process. Photos show the starboard bow side with a big slice taken out of it and no damage to the hull. When the first column out of four collapsed, its pair then became overloaded vertically by the deck by a factor of two (with added eccentricity exacerbating even more than 2), and collapsed, and then pulled the opposite two columns down with it. The entire deck relying on this column set then collapsed, then the opposite side span became unbalanced and collapsed as a consequence. The videos are an educational example of a “disproportionate collapse” of a structural system without any spare redundancy built in it.

    The bridges are designed to handle traffic loadings, and this bridge being where it is must have been designed to handle military type loads (70ton tanks and such), which means that the span itself was adequate.

    But if people were using this bridge since ’77, and if the original bridge designer did not foresee the possibility of a moving vessel impact, I would query, where were the port operator or government supervisor and their risk assessments all this time. I cannot imagine that nobody in the last 45 years hadn’t had a thought of a vessel impacting the bridge supports. Think hijack if not malfunction or juiced up pilot. Any timely risk assessment would have detected not possibility but a real probability of a ship hitting the principal columns set, and remedial measures should have been implemented. Meaning, either, build a dolphin designed to sustain impact of heaviest possible vessel travelling at 10+knots, (practically, sink the ship before it destroys the bridge)(practical and proven solution), or in the alternative, totally redesign the columns’ set to sustain such lateral impacts, perhaps by modifying it into a closed box structure which would have retained a great deal of residual robustness but would still be riskier than a meaty dolphin.

    1. flora

      Thanks for your comment. My quibble, if it is one, is that the bridge was designed and constructed in the early 1970’s and opened for traffic in the late 1970’s, 50 years ago. At that time, the huge container ships we see today were still in their infancy in terms of size, weight and general use. I wonder if that was a factor in the Key bridge design.

      I don’t know how the Dali ship compares in size to the largest container ships. Here’s a graphic comparing the avg. size of container ships from 1950’s to now.

      1. lyman alpha blob

        That’s what I’ve been wondering too – were these massive container ships in widespread use when the bridge was designed?

        And if they weren’t, how many other older bridges might be in danger now that these behemoths are everywhere?

        1. Benny Profane

          No. These ships were just starting to grow into monsters at that time. China’s economy was still dirt peasent based, not the factory town to the world it is today. And, if I remember well, Baltimore Port was just starting to grow, as the industry moved a ton of work from NY, to nust that powerful union. And, containerized shipping also helped eliminate those labor costs, because a lot of that was done by hand and machines on the dock.
          So, in the past 40-50 years, this is what developed, and you betcha a lot of people involved on ships and the port and traffic engineers imagined something like this happening, but put it on the back burner as somebody else’s job. A port in an awkward place, and a poorly designed bridge for the future. Whoops. But at least Uncle Joe is going to pay for a brand new one, and he’ll probably put train tracks on it!

          The price we pay for cheap stuff on Amazon.

          1. Altandmain

            There is a precedence for this. After the Exxon Valdez oil spill, all oil tankers had to be double hulled.



            This does mean higher costs in construction that will inevitably be passed onto the customer.

            But in this case, it’s cheaper in the long run to have fewer oil spills, which are very expensive.

    2. Yves Smith Post author

      This is extremely helpful!

      And I neglected to mention a key point you made prominently, that the navigation channel seemed way too close to the pier. The ship was out of control only a short time and at least a minute of those 2-3 minutes was it drifting forward, still in the channel.

      And I never thought of your additional point, that the bridge should have been designed to anticipate someone maliciously driving into a pier.

      1. Reply

        America is a very open country from the perspective of infrastructure exposure. There is some previously-assumed element of high trust in much of what people see and rely upon. Bridges are weak points, as are power grids, water supplies and public transit to list a few more obvious examples.

        How that trust has been eroded has many factors, one of which is the Because Markets mantra. A corollary to that factor would seem to be Never let a crisis go to waste. We will continue to pay literally and figuratively for the erosion and many reactions for decades.

      2. dandyandy

        The narrow channel, the malicious intent, DUI, those are all factors that can come to the fore as one goes through a lifespan of a capital structure like a bridge.

        But it’s the continuous assessments of all the new circumstances that the management is normally tasked with and which I see not having been performed in this case.

        Technical experts’ job is to think of unthinkable. They missed a big one on this occasion, sadly.

    3. flora

      I had to look up your term “dolphin”. I realized that’s exactly the way my uni’s old traffic control booths, with a person inside to either allow or disallow traffic onto campus during class hours, were built. The booths were set in the center of the road at the campus edge. The smallish booths were surrounded by a very stout concrete architecture that had a raised, bow-like appearance both front and aft, that curved around the booth like the sides of a canoe. (The booths looked like small tugboats.) The dolphins must have deflected more than a few vehicles judging from the dings in the cement over the years. No booth was ever hit by a vehicle, no booth worker was ever injured at work.

      Meaty dolphins does sound like an excellent idea for bridge supports. I am not a structural engineer.

    4. Peter

      The Sydney Morning Herald article on the collapse pointed out that the defensive mechanisms for the bridge were deficient in two ways: Firstly, dolphins were present, but the ship skirted them without impact, indicating that their placement was inadequate. Secondly, the “fender”, which surrounds the columns to prevent impact by a ship, was designed in the 70s for ships one quarter the size of the ship which destroyed the bridge.

    5. Glen

      Yes, I was surprised to not see any dolphins around the bridge. Just to the north of the bridge are two very large power poles with what looks like large protection zones (dolphins) around the base of the poles. Here’s an example of the dolphins installed around the Skyway bridge after a similar ship collision there in 1987:

      Still, the container ships are much more massive now that when these bridges were designed, and it’s notable that the MV Dali starboard bow projected so high up and far forward that is struck the support very high up, collapsing the support, followed by the whole arch.

      Sal at “What Is Going On With Shipping” has a good update here:

      MV Dali and Port of Baltimore Update – March 27, 2024

      I know this is being characterized as a black swan event, but I think that financialization/enshitification of our society/infrastructure makes it much more likely that such events can occur.

    6. redleg

      I was involved in the response to the 35W bridge collapse in Minneapolis. That bridge failed because of a gusset plate. The truss holding up the bridge was “fracture critical”, meaning that the truss was not capable of staying up if one component failed. That bridge was built in 1968. I have the plans.
      This bridge looks like a similar design- an arch truss that is fracture critical. I don’t have these plans, so this an observation not inside knowledge.

  3. Louis Fyne

    the Key Bridge opened in 1977. according to google-fu, back then the average container ship held about 3,000 containers, today 3,000 containers is essentially the floor for a typical container ship.

    There is a whole class of very large container ships, Ultra Large Container Vessel (ULCV), 3x the 70’s average, which can’t dock in any US port given the inability of US port infrastructure to handle a ship of such size.

    maybe in a perfect world, with a bunch of mitigating factors (smaller ship, more redundancies, less wind, etc), the disaster would have been averted .

      1. LY

        The ship is significantly larger than Panamax (5,000) , but less than the max for New Panamax (14,000). I remember the New Panamax standards since the Bayonne Bridge between NJ and Staten Island had to be raised less than a decade ago to accommodate the larger ships.

        The problem of these really large ships is not a decade old. With the state of risk management… we’re not a serious country.

    1. Benny Profane

      “can’t dock in any US port given the inability of US port infrastructure to handle a ship of such size.”

      And it’s not as though there’s anymore places on the East coast we can build a modern port to handle these things. It’s all become wealthy waterfront residential property.

  4. Matthew G. Saroff

    As an FYI, the kinetic energy of a 116,000 ton ship at 7 kts is about 694 MJ, which is equivalent to about 163 Kg of TNT.

    Note that pretty much all of this force would be focused on the bridge supports, so that is more like a shaped charge than a bomb in free air.

    1. jsn

      And spans sit on movement joints to absorb expansion/contraction and some amount of differential movement.

      The impact probably knocked the supports out from under their bearing points, with the larger inertia of the larger structure holding it in place until it was unsupported, then fee fall.

      I’ve never seen such a quick and total failure.

        1. The Rev Kev

          And as firefighters say, ‘Don’t trust the truss.’ And weren’t the Twin Towers all truss construction too?

          1. flora

            Mmmmm… Let’s not go there. Let’s wait for more information. Baltimore is still in recovery mode. Still working to find peoples fallen into the waters.

  5. Synoia

    Why was there no backup capable of very quickly restoring navigation? Again we don’t have a clear picture yet, but the big belch of smoke suggests the crew either tried to restart the engine or perhaps an auxiliary diesel engine

    1. Most ships of this class have 1 (large) engine, and rotorable thrusters instead of a rudder.

    2, Tugs are expensive, and if the Ship is newer, relies on swiveling thrusters for maneuvering, so eliminating the expense of tug assistance.

    3. Engines are machines. They fail.

    4. It would be interesting to know the maintenance cycle of this vessel.

    1. scott s.

      Well, I don’t think we understand yet what caused the bow to turn to starboard. Simply losing all power, even assuming the propulsion diesel shut down, the shaft would be slowing to a stop and going from memory so don’t quote me, but I think the steering gear ram would be in a hydraulic “lock” at last commanded position.

      We need a marine surveyor familiar with IMO requirements (minimums) or a Coast Guard Marine Safety Officer who would be familiar with requirements for operation in US waters.

    2. stickNmud

      I’m not an expert, but I think bow or stern thrusters are only used for maneuver in and out of the ship’s berth, not while underway in the shipping channel. Also, the MV Dali has a single engine and rudder. This account says there were two harbor pilots aboard, and back up generators need 30-60 seconds to start up. It also mentions the role of tides as contributing factor:

      Matthew Collette, a professor of naval architecture at the University of Michigan notes, “there’s one propeller on the ship. It is the only engine that can turn the propeller.”

      However, Collette speculates an electrical failure suggested by the video of the accident could have been a contributing factor. The lights on the ship could be seen switching on and off several times before it struck the bridge.

      He says the engine has redundant systems, but the fuel system requires electricity to keep fuel feeding it. A ship the size of the Dali “would have either three or four independent diesel generators” to provide electricity and another above the main deck ready to “automatically start in a blackout condition,” Collette says.

      “But it’s not instantaneous. It might take 30 seconds or 60 seconds” to start them and restore power to the ship, he says. Without electrical power, both the engine and the steering system could have been disabled in the critical moments leading to the collision, he says.

      While, the steering system is triply redundant, Collette notes, each of the backups is dependent on electricity to run pumps that then pressurize the hydraulics and activate the ship’s massive rudder.

      At the time of the collision, an ebb tide was also running, meaning that the current would have been flowing out of the harbor — the same direction the vessel was traveling. When a tide is running with the ship, it makes maneuvering more difficult, according to Collette. Compounding that difficulty, the collision occurred just one day past a full moon, when tidal current velocities are especially strong.

  6. ilsm

    Too many black swans.

    100k ton ship loses control over momentum. Complicit crosswinds veers the rudderless ship toward too small “pillars” with no guarding structure. The bridge is one long span over 1000m with two light supports either one damaged…..

    Similar to other famous US catastrophes nowhere is a damage effect model to study multiple black swans.

    Black swans in series would suggest a plan.

    1. Alan Roxdale

      This even is not a “black swan”. A black swan would be a pod of blue whales crashing into the bridge during a migration season.

      This is almost certainly the final result of operational and institutional decay. There were probably lots of safety procedures, speed limits, backups, and pilot boats in the harbour at one point, and one by one they were relaxed, rescinded, removed, and hurried on to make way for more traffic, more turnaround, and more profit.

      I’d call this the Chernobyl of American maritime transportation, but thankfully it happened late enough at night that only a few unfortunate people lost their lives.

      1. ilsm


        Looking at the Wiki on MV Dali. In port the ship is moved using a “forward thruster” powered by 4 generators, any one of which should operate the thruster. It is possible several generators were off line leaving the ship with a single source of failure to energize the thrusters…..

        That would be an operational error!

        Since the ship is largely intact and standard procedure for generators id to log on and off time….. That possible cause should be run down.

      2. DeltaGlider

        I agree with Alan Roxdale. I will wait for further comment from maritime and structural engineers.

        As we have seen in recent episodes in the rail industry (Norfolk Southern) and air transport industry (Boeing 737 Max), the temptation to hyperfocus on profit can motivate you to opt out following basic, obvious safety measures. No conspiracy needed.

        If I was in charge of a port, some obvious “what-ifs” I’d consider for a ship transiting critical infrastructure include:
        – a ship should have a backup power system
        – a ship should have a backup directional control system
        – backup systems should be running until the critical phase is over
        – a ship lacking the above should have a tug(s) escort

        I find it hard to believe such aspects were never considered, but easy to believe they were ignored.

      3. CA

        “This is almost certainly the final result of operational and institutional decay. There were probably lots of safety procedures, speed limits, backups, and pilot boats in the harbour at one point, and one by one they were relaxed, rescinded, removed, and hurried on to make way for more traffic, more turnaround, and more profit…”

        Really, really helpful explanation-outline. I do appreciate an elegant outline.. Thank you so much.

    2. flora

      Or very bad luck.

      “When troubles come, they come not single spies, but in battalions.”
      – As Shakespeare did not quite say. / ;)

  7. Henry Moon Pie

    Personally, I’m in the it’s-all-DEI’s-fault camp. /sarc

    Not directly related, but I checked in on the news at noon, and they’re saying the area most likely to be hit by this is the Midwest. Guess lumber at Home Depot will be be headed back up.

    On to explain to Andrea about how this will impact the Greenspans’ bottom line was the charismatic Janet Yellen in her Beatles-tribute hairdo. I’ll cop to my still unredeemed sexism and ageism likely playing a role, but whoever appointed her to Fed chair or SecTreas? Andrea was all animated, trying to set up one of Joe’s plethora of surrogates, but Yellen was as dead-eyed, unsmiling (where’s your smile?) and bummer spreading as possible. I think about Biden’s cabinet. Blinken looks like a scarred rabbit. My nickname for Jake Sullivan is Kaa from Jungle Book. Pete hides in the hospital bed, while Austin secretly checks his PSA.

    Did Warren Harding have worse? Will Trump’s cabinet be even more ridiculous? This is a collapse of epic proportions.

    1. mrsyk

      The dysfunctionality of state is laughable. A shambles. Perhaps this explains Lina Khan’s survival in some way.

  8. Es s Ce Tera

    When/if they regained any power they should not have put the boat in reverse, to avoid prop walk, but I feel the captain and pilot would have known not to, assuming they were even able to. Also the smoke was showing the wind was brisk and may have been coming from the fore to starboard and a boat with such high topsides would have been acting like a giant sail, so I think it’s going to come down to the wind and currents being the decisive factors, coupled with engine failure.

    One thing that’s bugging me is that backup generator seemed to take an awful long time to fire up, I think diesel generators are faster than that? And also, wouldn’t a modern ship have backup battery banks? So if the electrical went out it would have been a brief flicker? Is it possible the smoke isn’t from the generators but possibly an engine room explosion which also caused the shipwide electrical to get temporarily knocked out? I dunno, there’s something off about the electrical aspect.

    1. ian

      I was wondering why not have the backup generators already running at critical moments like entering or leaving ports? I mean, what’s the harm having them run for an hour or so?

      1. Es s Ce Tera

        Indeed, could it be they probably were running? I guess we’ll have to wait to find out.

    2. ilsm

      See above there are 4 generators any one of which should have powered the thruster that is used in port.

      The main propulsion with a huge Hyundai diesels direct drive is not used in port.

      Per wiki on the ship.

      All witnesses are available.

    3. BillC

      … redundant generators and backup batteries …

      Yes, the power sources ARE redundant, but the principal distribution SYSTEM may not be. Airliners have distinct redundant electrical and hydraulic systems, each powering a different collection of loads, but I don’t know that box ships do.

      I saw somewhere (?) a comment that the Dali had some power outages on board while in port in Baltimore. If there’s an intermittent short circuit, overload, or AC sync problem on the main shared distribution system that’s hard to identify and isolate, even redundant power sources won’t prevent outages.

  9. Alan Roxdale

    “The vessel went dead, no steering power and no electronics,”

    And no software control. I’d wager several ships systems had to wait for Windows boot ups, online logins, and automatic update routines before the helmsman could even think of entering commands. I’ll further guess that the crew had to re-insert their key-fobs or passwords as well. I am not making a joke.

    1. Lost in Africa

      I work in the mining industry, (with and without self generated power). Generally, all electronic systems are connected to a UPS to prevent loss of PLC’s, SCADA’s and other monitoring systems in the event of a power outage. They even have their own backbone network and are generally not connected to the internet to prevent hacking and other malfeasance. I would have thought that a ship of this size would have the same back ups installed as a bare minimum.

      The bridge incident is truly tragic, but not the only hazards ships will face on the high seas.

  10. BillC

    Today’s “box ships” are designed for economy at the expense of redundancy. One huge diesel engine (piston diameter ca. 1 meter) drives a solid propeller through a solid shaft, red line around 90 RPM. No transmission, no clutch, no variable pitch. Nice and simple, but ONE of each.

    “Reverse gear” means: stop the engine, switch controls on certain components (fuel injectors, …?), and restart the engine using large volumes of stored high-pressure air. Rudder control is hydraulic using electric pumps powered by diesel generators, not the main engine. When the engine or electrical system fails, you have an uncontrolled but massive vessel drifting on momentum, tide, and wind.

    These vessels have traded reliability for economy, and that’s what keeps our stores full of merchandise that arrives cheaply by container from overseas. Unless we continuously upgrade our port infrastructure to be robust enough to survive certain but unpredictable “accidents” or we force the container trade to transition to more reliable and costly vessels, we’ll continue to see events like this every few years. That’s the price of “cheap” … and of the profits it generates.

  11. Martin Oline

    I suspect when “Alexander Mercouris regularly claimed that bridges are seriously over-built”, he is speaking of the bridges over the Dnieper but your experience may vary. I looked at images of the Kerch bridge yesterday and it has one suspension area for ships with huge dolphins protecting the piers. Very serious engineering. Wiki has pictures of that which can be enlarged.

  12. wendigo

    Wikipedia describes a continuous truss bridge as cheaper to build than a bridge with a series of simple trusses.

    Only problem seems to be it requires every part to stay standing.

    Gcaptain dot com and its forum have some information/speculation.

    1. Darius

      A continuous truss is also a magnificent structure to look at and drive across. I’m thunderstruck that Maryland DOT didn’t protect the bridge from vessel collision 44 years after the Tampa Bay disaster.

  13. East Dadeville

    In addition to concerns over proximate factors contributing to the bridge collapse, with official findings some time in the future, the collapse was an obtrusive illumination of a history of documented and sanctioned labor problems with the ship’s owner(s) who chartered the boat to a major international shipping company.

    Extraordinary search and rescue efforts were undertaken to locate the workers repairing the roadway on the bridge and who ended up in the water when the bridge collapsed. It’s reported two were rescued. All the repair workers and the supervisor appear to be foreign born subcontract employees working a low-traffic, midnight shift.


  14. VietnamVet

    As mentioned in the second video, the cargo ship Ever Forward ran aground in the Chesapeake Bay in May 2022. Off the top of my head, Ever Given, a colossal container ship crashed in to the bank of the Suez Canal in March 2021 blocking it for six days. Three days ago, a Chinese-owned oil vessel was hit by Houthi missiles in the Red Sea. Two bridges were brought down in the 1970s by ships in Florida and Tasmania. Climate change drought has lowered the volume of traffic by a third in the Panama Canal. These are not black swans. Maryland has to consider if the piers of the Bay Bridges are secure from destruction by container vessels. Will Congress pay to upgrade them too?

    The era of cheap transport of global goods to Europe and the Americas is over. Without peace and safe transport of goods, shortages/inflation and upheaval are assured. To survive, future planning is a necessity to balance the risks/costs verses the benefit to the people. This means acknowledging reality.

    1. MajorMike

      Let’s acknowledge reality. . .

      Adding “Climate change” as an adjective to the word “drought” is a meaningless effort to be politically correct. Yes, there is a drought in Panama that affects the operation of the canal. The canal locks depend on a water supply from Lake Alajuela (formerly Madden Lake), which is a manmade reservoir on the Chagres River which is controlled by spillway operations to meet the demands of shipping in the canal, which is downstream from Lake Alajuela. In 2010 the canal was shut down because of too much water in Lake Alajuela. 2010 was a “LaNina” year which typically causes intense rainfalls during the wet season. 2023 and 2024 were strong “El Nina” years which typically causes drier wet seasons.

      The El Nino drought event of 1997-1998 was much more severe in Panama than the recent El Nino related drought event, however there was no major effect on the operation of the Panama Canal. Why? This event occurred prior to the widening of the Canal (2006-2016). After widening the water demand from Lake Alajuela skyrocketed because of the displacement requirements for larger container ships passing through the canal.

  15. TomDority

    Right now, we have more questions than answers.
    My one question is why Dolphins were not added to/adjacent the structure prior to this event.
    As to engineering to make the loss of one pier non-critical – well if you did that you would just forego the pier — oh wait — physics, gravity, strength of materials, expansion, contraction etc. – for that matter, why would you design a tire that could be punctured, a program that can crash, or an economic system that bubbles and bursts.
    Could speculate all you want but bottom line, Get you causes together and figure the way forward so that current and future designs and systems are upgraded and made to perform the best they can – never perfect in this universe – one other thing, ensure (as best is possible) that proper maintenance and procedure in place — This of course, will still never ensure that it is, or ever will be 100% correct
    Just my, maybe, two cents worth.

  16. Telee

    Eight months before the collapse of the bridge in Baltimore harbor, the labor department sanctioned the Maersk shipping conglomerate for retaliating against an employee for reporting unsafe working conditions aboard a Maersk ship calling such practice repugnant and unlawful. The employee was fired for voicing his concerns. The Seaman’s Protection Act was violated and one has to question whether the government is actually enforcing these laws. Company policy required workers to report concerns to the company and not the regulators. In other words higher priority was given to profit rather than safety. My guess is this a common practice in the shipping industry as well as other industries. Think Boeing and many others.

  17. notabanker

    I am not an engineer or sailor of any sort and don’t have a “camp” on this, I’ll leave that to those better qualified to speculate, but i did lift a couple/few factoids out of the YT’re who had a CEO of a shipping company on his channel last night:
    – Throwing the anchors seemed to be a last ditch effort and likely futile at that point. In fact he speculated hat could have caused more casualties to the crew than benefit to the disaster
    – Pilots are paid in the specific jurisdiction to navigate through those waters by the tonnage, and tugs come out of the over all cost borne by the shipping customers, but also from the tonnage formula they get comp’d on.
    – The cost of liability is transferred to the shipping container customers under 100’s of years old maritime law, going back to traditions set when crew members were encouraged to throw any cargo overboard to save the ship without fear of reprisals from a specific customer. Will be interesting to see Mersk duck liability for this, but there is ample example of freight sitting in Panama un claimed with millions in liability associated with it and no cargo insurance coverage by the shipping customers.

    1. ChrisPacific

      I’ve heard post-mortem discussions of other similar (much less serious) incidents. Throwing anchors is done for insurance purposes as much as anything, to demonstrate you weren’t asleep at the wheel, drugged up etc. and you were actively taking what steps you could to mitigate the situation. If you collide with a land based structure and your anchors are still shipped, people will ask why, and the microscope will focus on the pilot even more than it already does.

      They rarely do much to stop anything, and especially not in situations like this where there is so little time.

  18. dogwood

    Sal Mercogliano of What’s Going on With Shipping (you linked to his side by side analysis above), also does an informative interview with tons of very interesting details with John Konrad (“…licensed to captain the world’s largest ships and has sailed from ports around the world…”) of gCaptain. Sound is a little muffled in the beginning but overall just fascinating.

    1. VietnamVet

      This video is well worth the time to watch. Getting accurate timely information is precious. They mentioned that the maritime industry is siloed. This is true across the board in the 21st century West. It is how corporate profits are made e.g. healthcare. They said that the US Navy privatized all of its salvage operations and got rid of its salvage ships and equipment — just like the US Army privatized logistics (and logistics wins wars). They said that the US Navy must be in charge of clearing the Key Bridge steel and concrete from the shipping lane into the Port of Baltimore or the ship owner, will hire the cheapest salvage company, and it will take years to finish.

      Who is liable and to what degree needs to be determined from the Dali owners – Grace Ocean Investment, the ship leasing company – Synergy Marine Group, lessee – Maersk and/or the container owners under US and maritime law.

  19. Karl

    I doubt an insuer would have covered the bridge without dolphins and other safety features, hence probably not insured. Insurance is another risk management control that may haveen lacking.

    1. Rip Van Winkle

      Not uncommon for toll bridges to have insurance, for property and loss of income. TRIA terrorism option / add-on. Don’t know about this one.

  20. flora

    adding: 8 knots is per hour per an online conversion calculator ( for us non-mariners) is roughly 9.2 miles per hour. That is 1 knot = 1.15 miles per hour. If this helps anyone understand the ship’s speed situation. That is, 1 knot per hour is only slightly more than 1 mile per hour.

    1. flora

      adding, and to go on too long: it’s not only speed but also weight. A canoe hitting a pier at ~9 miles an hour is nothing to the pier, for example.

  21. Karl

    Very cheap and foul bunker fuel is typical in diesel powered shipping. Dirty fuel could well have been a root cause.

  22. Tom Pfotzer

    A few points:

    a. power fail-safe systems for navigation electronics would have to be present. I will fall out of my chair if the control systems for that ship didn’t have a battery-based UPS with diesel generator backup which would have come on automatically within 30 secs of power failure

    b. power failure implies a diesel-powered generator on the ship failed. That generator would have to be independent of the main propulsion engine (too slow RPMs to gen AC 60 cycle power). That generator was not fueled with bunker fuel; it was diesel powered.

    c. It’s plausible to me that the main power generator failed, and that caused momentary loss of rudder control.

    The core question for me is why the backup generator didn’t start and connect-in. The ship would very likely have had a special transfer switch, designed for a multiple-generator environment, to sense power failure, start the backup generator _at the moment_ the primary generator failed, and transfer the load to that backup generator. That should have been automatic, and fast (30 secs max).

    The fact that the power went off, then on, then off suggests that there’s a problem with that transfer switch, or the backup generator didn’t successfully start and continue running. Transfer switches are designed to switch to backup a few seconds after the primary power source fails, and stay with the backup for several minutes after the primary source is restored, in case the problem with the primary is intermittent failure, not constant failure.

    I’m still not clear on exactly what ship-board electricity-generating equipment failed, and why the backups didn’t come up and transfer correctly.

    Electrical power seems to be the root-cause of the problem. Why didn’t it work correctly?

  23. dirke

    Everyone seems to have everything covered. The next question is “How long will it take to get the navigation channel open?” The bridge is not needed for port operation. To remove the damaged bridge structures from the channel shouldn’t take to much time.

  24. Benny Profane

    Holy mackerel. I’m watching a press conference from Baltimore of officials supposedly informing people of the situation, like you usually see after major incidents, but then it devolved into both Maryland senators just mouthing cliches, and then, and then, they trot out Tom Perez as a “spokesman” for the Biden WH, and the first thing he says is the Biden family is no stranger to this kind of tragedy (honest to God) and proceeds to do a quasi campaign speech praising Joe’s awesome response to all this. it was really gross. He did it at a rally level volume. then he went into repeating it in Spanish, which I don’t understand, but said Presidente! four times before CNN, yes, CNN, decided to pull the plug on that. These people are depraved. What an awful bunch of people in charge.

    1. flora

      omg. Has ye olde B admin/campaign has gone full Monty Python and doesn’t even know it? Too funny, or horrible, or sad if so.

  25. Old Sarum


    If the ensuing investigation does not emphasise the lack of adequate dolphins to protect the bridge I will not be surprised as the US seems to have lost its organizational & technological mojo and has become a “case study”.


    ps Check out Dan Gryder’s YouTube channel and get a whiff of what he thinks of the NTSB.

  26. David in Friday Harbor

    Globalization and cost-cutting are the culprits here, although the dolphins surrounding the bridge supports were a joke.

    The MV Dali is crewed by 22 Indian nationals at the very bottom rung of the maritime compensation sale; virtual slaves. Their mission is to do the bare minimum to maintain the vessel with their main focus on conserving fuel. A G-Captain poster reports rumors that the crew complained that power had been failing continuously during MV Dali’s 36 hours at the quay, possibly due to faulty refrigeration units in the cargo tripping the ship’s circuit breakers.

    A massive Neopanamax container vessel isn’t maneuverable in port under the best of circumstances due to its single-shaft fixed-pitch propeller. The loss of power rendered the vessel impossible to steer as the single bow-thruster required electrical current to function. Under the command of a Baltimore Pilot unfamiliar with the ship’s propulsion systems, if the main engine was reversed once it got turning again, cavitation and torque-thrust would temporarily render the rudder useless (as apparently happened to the Titanic) and probably caused the “hook” to starboard just before the collision. Dropping the anchor at that point was merely a gesture.

    But we can get a bunch of ticky-tacky from ScAmazon and Walmart — cheap!

  27. PlutoniumKun

    Just as a point of comparison, there was a not dissimilar event last month in Guangzhou – a barge took out the span of a cantilever bridge after hitting one of the piers. In that case, there was a big stoke of luck in that a bus was destroyed but there was only a driver on board, it could easily have been a mass casualty event. It’s not clear in this case what caused the barge to lose control.

    As a general rule, a bridge can be made robust by either making it very massive and rigid, or by making it flexible enough to take all reasonable loads. When there is a need for a very long span for navigation reasons, usually the latter is the preferred option. Truss structures are the least elegant, but most cost effective designs for when long spans are needed. But we’ve seen the drawback of trusses – when they are fatally compromised, the entire structure goes down.

    My understanding of dolphins is that they are primarily useful for deflecting collisions, not stopping a heavily loaded vessel on a direct collision course. It all depends of course on anticipated circumstances – it’s possible that the original calculations were based on an assumption of smaller vessels typical of the 1970’s. But it still surprises me to see no visible protection whatever. It’s not uncommon for reasonable design assumptions made decades ago to become problematic as circumstances change.

    I think a possibility is that dropping the anchor made things worse – it caused the course deflection into the bridge.

    1. David in Friday Harbor

      I doubt that the anchor did anything. They didn’t have the distance to pay-out enough chain for the anchor to grab the bottom, let alone for the rode to stop the forward motion of the vessel.

      The AIS track shows a classic case of transverse thrust caused by a reversing single screw propeller. The vessel will want to twist her bow to starboard (right) and twist her stern to port (left) if the rudder isn’t biting water due to cavitation.

      1. PlutoniumKun

        Since I wrote that I read quite a convincing outline by a former engineer on what happened – essentially, an electrical breakdown causing the first loss of control, a recovery, followed with a double ‘trip’ caused first by putting the engines into emergency reverse, and then by activating the forward thrusters. The latter could have caused the change in course towards the bridge.

        I think as with most accidents of this nature fairly simple explanations are best, although there are usually a conjunction of cascading failures.

        1. David in Friday Harbor

          The MV Dali is equipped with a single bow thruster. Normally such a device would only be capable of providing 90-degrees of lateral thrust intended to move the bow of the vessel from side-to-side during low-speed maneuvers.

          The more significant problem appears to be cavitation produced by reversing the propeller. A sudden reversal will create a “cavity” in the water, rendering the rudder ineffective because it has no water to deflect. I have a USCG Coastal Navigation Certificate and was close friends for many years with a Ship’s Master for Exxon. The physics of cavitation is well-understood.

          The issue seems to be that control of the rudder and the bow thruster are dependent on diesel-generated electricity. The ship temporarily lost electrical power and all ability to steer. The pilot appears to have decided to “bail” on threading the bridge without steering. However, reversing the engine/propeller only made his problem worse due to transverse thrust turning the vessel’s momentum starboard (right) out of the shipping-lane directly toward the bridge support. You can see it happen on the AIS track.

          It’s the Titanic problem — reversing her screws turned the ship into the iceberg. Depending on the current, the pilot might have been able to simply use the ship’s forward momentum to “coast” along the shipping lane if he hadn’t called for Emergency Reverse Engine. The bow thruster probably had very little effect and any that it did would have been to straighten the ship’s track to port (the left).

          The behaviors of boats are very predictable but the physics are very difficult to overcome!

          1. ChrisPacific

            For the uninitiated, cavitation = lots of bubbles (air, basically).

            Kind of hard to steer a 100k ton ship by pushing against air.

  28. mrsyk

    Just watched NTSB Chair Jennifer Homendy brief the media. There are a number of containers of hazardous materials onboard the Dali. Twice, she specifically mentioned corrosives, flammables, and lithium batteries. She stated that there are breached and submerged containers.

    1. ChrisPacific

      Reminds me of the MV Rena which lodged on a reef off the coast of New Zealand and gradually broke up over time, shedding containers over time which cracked and released their contents into the wild (we got to guess which ones contained hazardous substances). And of course, a good deal of oil.

      The cleanup was a multi-year effort. Access should be a good deal easier for this one, but it also looks to be considerably larger.

  29. eg

    I see “efficiency” over robustness/resilience because markets/profits.

    Penny wise, pound foolish …

  30. Altandmain

    Yves, one thing to keep in mind about Alexander Mercouris and his comments about bridges being overbuilt – that’s referring to the bridges that the USSR built in Ukraine.

    The USSR overbuilt bridges to survive a major catastrophe (think about nuclear conflict – a bridge won’t stand a direct hit near the center of the blast of a multi-megaton warhead, but if it is far enough, overbuilding can cause it to survive).

    That doesn’t mean that the USSR and now Russian bridges are invulnerable. To give an example, the Kerch Bridge has been subject to multiple attacks from Ukraine, mostly from munitions supplied from the West. Usually it means that the bridge takes minor damage and the collapse is localized. There are still fatalities, but they are only in one small section in close proximity to the blast. One important point is how rapidly the Russians are able to repair the damaged section of the bridge and bring the bridge quickly back into service.

    Note how the leak about the German proposed Taurus strike required a large bombardment of missiles to collapse the bridge. It’s an indication of how tough the West expect the Kerch Bridge is to destroy. One wonders how a comparable bridge in the West would stand up to such a theoretical attack.

    The same overengineering cannot necessarily be said about the US made bridges. Even many USSR bridges may not be so overbuilt, you’d have to do an analysis on a bridge by bridge basis.

    In 2021, the American Society of Civil Engineers indicated that 7.5% of all bridges in the US are in poor condition.

    Evidently, the US has suffered from many years of underinvestment in infrastructure. Note how the report even wanted just a few billion per year – I’d be very interested to see how much progress the US has made on this. In all likelihood, the US has spent money on other areas (such as war) and under-invested. The next infrastructure report card is due in 2025.

    It’s too early to draw final conclusions. When the final report from the NTSB and other agencies comes out, I suspect that we will find out that there were multiple points of failure.

      1. mrsyk

        Bridge detail as per the NTSB via the video linked above, starting at about the 17:45 mark
        The Key Bridge is/was a “fracture critical bridge”, defined by having no redundancy. Thus the whole bridge coming down with one shot. Other data, 30,767 vehicles per day usage. Of approximately 615,000 US bridges, 17,468 are defined as “fracture critical”.
        Note, NTSB chair Jennifer Homendy is running on fumes in this video. This is an excellent opportunity to observe her.

        1. mrsyk

          I suggest watching the tugboat question at about 25:50 for a telling moment. It’s the only point during the interview where she loses her focus for a very brief second.

  31. Bobby Gladd

    I live in Baltimore. My kids own a sailboat, moored in Fell’s Point (my civil engineer daughter-in-law is a veteran sailor and former sailing instructor). We’ve sailed around and under that huge bridge. We’re all still dumfounded by this. A terrible tragedy and enormous long-term mess.

  32. Matthew S

    FYI, a recent Washington Post article says “In the case of the Dali, Ralby said the possibility of a cyberattack should not be dismissed. It’s also possible that the ship had a purely mechanical failure in one of its critical systems.”

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