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Several dozen ships lost propulsion in Maryland waters before Key Bridge collapse: ‘You’re basically just drifting’

Baltimore Sun reporter Alex Mann
PUBLISHED: | UPDATED:
Francis Scott Key Bridge collapse.
The wreckage of the Francis Scott Key Bridge is seen beyond the stern of the container ship Dali three weeks after the catastrophic collapse. (Jerry Jackson/Staff)

After delivering a load of sugar to the Domino refinery in Baltimore’s Inner Harbor two winters ago, a 567-foot bulk carrier departed for Georgia but didn’t get very far before experiencing engine trouble.

Not long after the Nazenin sailed underneath the Francis Scott Key Bridge, a mechanical malfunction cut the flow of cooling water to the ship’s main engine, disrupting the ship’s propulsion. Its crew dropped anchor just outside the channel in the Patapsco River to make quick repairs, according to a Coast Guard incident report.

Having replaced a “cracked cylinder liner” the Coast Guard attributed to poor maintenance, the Nazenin sailed south to the Annapolis Anchorage, just south of the Chesapeake Bay Bridge for the repair to be inspected. A day later after it resumed its voyage south in the Bay, the ship’s “oiler on watch,” who the report said was inadequately trained, made an error that caused it to lose propulsion again and it had to drop anchor again.

Crisis was averted both days, despite the ship twice being rendered mostly adrift not far from bridges providing passage to tens of thousands of motorists daily. At least 40 other times since 2021, cargo vessels experienced a complete loss, or reduction of, propulsion, power or steering while sailing in Maryland waters, according to a Baltimore Sun analysis of Coast Guard reports.


Incidents involving loss or reduction of propulsion or power, 2021 – present

There have been at least 42 incident reports indicating a vessel experienced a loss or reduction of propulsion, power, steering or maneuverability from the start of 2021 to April 18, 2024, in Maryland waters. Incident location is approximate.

Map: Annie Jennemann, Source: U.S. Coast Guard


Those incidents are rare — hundreds of ships call in Baltimore every year — and generally minor. They happen at the dock or tugs assist the ship or it drops anchor harmlessly, but catastrophe came in the early morning of March 26, when a massive cargo ship apparently lost all power while approaching the Key Bridge and crashed into one of its critical support piers. The span collapsed immediately, sending six construction workers filling potholes plummeting to their deaths, indefinitely disrupting Baltimore’s busy port and permanently altering the skyline.

What went wrong aboard the Dali, the 984-foot ship that weighed 112,000 tons when it struck the bridge, and whether it could or should have been prevented, is the question at the center of parallel probes by the National Transportation Safety Board and the FBI. The former investigates with an eye toward preventing another tragedy, while the latter looks for potential criminal charges.

Experts believe the Dali suffered a blackout, or a complete loss of propulsion and electrical power, as it approached the bridge. Such events are rare, but not unheard of. A ship losing propulsion, or the ability to turn the propellers that drive vessels forward or backward, is more common but still statistically unusual. Both can be terrifying.

“It means you’re dead in the water,” said Thomas Roth-Roffy, a former NTSB marine investigator of almost two decades and a Coast Guard-licensed chief engineer. “You can’t go ahead or astern. You’re basically just drifting. And depending on how long the propulsion failure lasts, you can run into big problems: grounding, collision or allisions with bridges.”

At the same time, vessels losing propulsion have rarely been publicly noteworthy. Oftentimes, experts say, it happens at sea, where the risk of crash or casualty is low, and well-trained engineering crews usually can make repairs before anything bad happens.

“It’s all about timing, time and place,” said Kevin Calnan, an assistant professor of marine transportation at the California State University Maritime Academy. “Normally when this happens you’re in the open sea in the middle of the Atlantic or Pacific Ocean, and it’s not really such a problem. You’re just going to float until you can get things figured out.”

“In the situation like Baltimore,” he continued, “it was a perfect storm of everything that could have gone wrong did go wrong at the exact time where it shouldn’t have gone wrong.”

But the Key Bridge collapse is not the first time a wayward ship resulted in tragedy. In 2015, the U.S.-flagged cargo vessel SS El Faro lost propulsion in the middle of a hurricane and sank near the Bahamas along with its 33-person crew. Six years later, a 623-foot bulk carrier lost steering and crashed into an office barge on the Lower Mississippi River, injuring one person and causing $6 million in damage.

Ships that experience a loss, or disruption of, power or propulsion in American waters are required to report the incident to the Coast Guard, which produces reports explaining the problem and what caused it.

The Sun examined more than 1,300 such incident reports for freight ships from the beginning of 2021 to date. More than half involved a vessel’s loss or reduction of propulsion, power or steering. Forty-three happened in the Coast Guard sector encompassing Maryland before the Dali, for which the agency hasn’t released a report.

Although that figure represents what is likely a small fraction of overall vessel traffic to Baltimore, it’s still “too many,” Roth-Roffy said, “because every time you lose propulsion, it’s a nightmare.”

Many of the vessels lost propulsion near shipping terminals in port. For some, it happened while sailing in the Patapsco River and Chesapeake Bay. All of them were on journeys requiring them to pass beneath the Key and Bay bridges at some point — twice, in all but two cases. Those two ships were en route to the Chesapeake-Delaware Canal, which also requires bridge navigation.

“The hardest part and most dangerous part of any transit for any of these ships is when they come into port, because God forbid something happens, that’s where there can be a devastating impact just like we saw in the Key Bridge crash,” said Roland Rexha, secretary/treasurer of The Marine Engineers’ Beneficial Association, a maritime union with roots in Baltimore and a training school in Easton.

The freighters that lost power or propulsion ranged from 567 to 1,203 feet, more than 200 feet longer than the Dali. Fifteen hailed from countries labeled “high” or “medium” risk flag administrations by the Coast Guard in 2023 because their ships failed comparatively high proportions of inspections at American ports over the past several years and were temporarily barred from going to sea.

Nineteen ships that lost propulsion in Maryland waters had experienced similar issues on another occasion in the approximately three-year range of reports The Sun reviewed.

The MSC Tomoko, a 1,089-foot Mediterranean Shipping Co. container ship from Panama that experienced reduced propulsion “in the vicinity of” the Bay Bridge in February 2022, had lost propulsion five days earlier in New York, according to the Coast Guard. A 650-foot U.S. government vehicle carrier, the Cape Wrath, lost propulsion in the Chesapeake Bay because of “equipment failure” — one of five reported problems over about as many years.

Both of those ships made repairs and sailed on.

“A repeat of a propulsion failure should kind of raise a flag to the regulator and the classification society to give them a little more attention in terms of inspection and oversight,” Roth-Roffy said. “And certainly the owner of the ship should be tracking failures because it’s their ship, or the operator, because any accident they can be liable for.”

Apr 5, 2024: A view from Riviera Beach of the Francis Scott Key Bridge wreckage with removal underway after the Singapore-flagged container ship Dali struck one of the supports last week. (Karl Merton Ferron/Staff)
A view from Riviera Beach of the Francis Scott Key Bridge wreckage with removal underway after the Singapore-flagged container ship Dali struck one of the supports. (Karl Merton Ferron/Staff)

Five days after Dali struck the Key Bridge, the Singapore-based companies that own and manage the container ship filed in Maryland’s federal court to absolve themselves from or limit liability stemming from the disaster. U.S., Maryland and Baltimore officials have pledged to hold the companies accountable for the crash, if the investigation supports legal action.

NTSB investigators have homed in on the Dali’s engine room, calling in support from Hyundai, the South Korean company that built the ship, to help them retrieve data about its electrical power system and circuit breakers.

Citing an anonymous source with knowledge of the situation, The Associated Press reported that the Dali experienced apparent electrical issues before it left the Port of Baltimore. That person said alarms went off on the ship’s refrigerated containers while it was still docked, likely indicating an inconsistent power supply.

Crews are supposed to test their ship’s engine, generators and switchboard before leaving a port, but Rexha worries that mariners on some international ships may not feel empowered to raise potential safety issues.

“It’s harder when you’re making less than minimum wage in a country where you are very lucky to have a job like this to be able to speak out against the company, because they won’t hire you again,” he said. “We’ve seen the ships get bigger. We’ve seen the crews get smaller, all in an effort to maximize the amount of money they make, and they do it on the workers’ backs.”

Former merchant mariner Sal Mercogliano wants to know more about what happened to the Dali when it was docked.

“Sometimes when you plug in refrigerated containers, they can overload the system and you don’t lose power to the ship, you lose power to the reefers,” he said, referring to the cooled containers. “It’s like blowing a fuse in your house — you didn’t lose power to your house, you just lost a fuse in a room or something.”

“The question is,” he added, “is it the full power of the vessel? If the ship goes dark, that’s something wrong.”

On cargo ships, the engine spins the ship’s propeller, thrusting it forward or backward, while separate generators produce electricity for the vessel. The engine relies on electricity for pumps that inject fuel and circulate oil and water to keep components lubricated and cool.

Myriad causes could lead a ship to lose power or propulsion, or to experience a complete blackout, typically coming down to failures of either the ship’s co-dependent electrical and mechanical systems, experts said. The Coast Guard reports reviewed by The Sun cited equipment malfunctions and human mistakes as causes for the ships losing propulsion.

Routine vessel vibrations jarred parts loose. A second engineer on a ship that didn’t have an alarm system for the main engine’s air compressor didn’t realize it was on manual, rather than automatic mode, leading to low pressure that caused the engine to shut down. A defective sensor led to a lack of cooling oil for another vessel’s engine.

When a ship’s automated engine monitoring system recognizes a problem, it cuts the motor off to avoid costly damage, Mercogliano said.

“They’re designed to protect themselves,” he said.

The 691-foot Grande Cameroon, of Italy, was on its way to Baltimore when it experienced a complete blackout in the Chesapeake Bay, just south of Tilghman Island. According to the Coast Guard, the ship lacked proper sensing equipment to recognize temperature changes in a steam line connected to one of its fuel tanks.

“A blackout requires more time to reset compared to just a loss of propulsion,” said Mark Phillip Laurilla, a chief marine engineer based in the Philippines, in an email. “Loss of propulsion doesn’t happen all the time but it happens often enough that some companies send their officers to simulator training particularly for this type of scenario.”

Students at Cal Maritime run through scenarios in simulator-based classes.

“We’ll run a scenario where we’ll throw all sorts of situations at them, total loss of steering, total loss of propulsion … so our students really get familiar with those emergency procedures, and they become second nature,” Calnan said.

In November 2021, a 981-foot, Liberian-flagged container ship lost propulsion in the Patapsco River, after going under the Key Bridge en route to Seagirt Marine Terminal. Tugboats guided it back out and down the bay to the Annapolis Anchorage for repairs. The Coast Guard report said the crew aboard the Agios Dimitrios failed to calibrate a component of the main engine.

Video of the Key Bridge collapse showed the lights aboard the Dali go out and then flicker as it approached the 1.6-mile span. A local pilot, who was on board to guide the ship out of the harbor safely, reported losing all power, including the ability to steer, in a “mayday” call shortly before striking the bridge.

Experts who watched the footage have postulated multiple possibilities, from electrical failures to contaminated fuel to human error.

“What happened to the Dali was not one generator failing, but an entire system,” Laurilla said. “It is highly unlikely that all of their generators were in poor condition. So something common to all of them caused the problem and forced them to shut down. The only common denominators would be fuel or switchboard problems.”

Baltimore Sun reporter Annie Jennemann and editor Christopher Dinsmore contributed to this article.