NTSB Releases Preliminary Key Bridge Report

THURSDAY, MAY 16, 2024

The cargo ship that caused the Francis Scott Key Bridge collapse in Baltimore earlier this year reportedly had a pair of “catastrophic” electrical failures minutes before the crash, as well as two blackouts the day prior, the National Transportation Safety Board found.

According to the 24-page preliminary report, the outages were triggered by two critical circuit breakers tripping, causing several pumps for the ship’s propellor and its rudder to stop working.

Collapse Background, Investigation

The bridge collapse occurred around 1 a.m. on March 26 after a container ship ran into one of the bridge's supports. Video and images showed the collapse, with part of the bridge landing on top of the shipping vessel. 

Maryland Governor Wes Moore confirmed at a press conference that day that the cargo ship Dali had reported losing power just before it crashed. Moore said that an emergency call from the ship allowed officials to limit traffic on the bridge before the crash, as the structure typically sees thousands of vehicles per day.

Moore also reportedly declared a state of emergency after the incident and said that he was working to get federal resources deployed. The Federal Bureau of Investigation was on the scene and have since confirmed that there was “no indication of terrorism as a motivating factor.”

Maryland State Transportation Secretary Paul Wiedefeld said that eight construction workers were on the bridge at the time of its collapse. Following the accident, two were rescued from the water, with one sent to the hospital and the other described as “okay.” The bodies of all six victims have been recovered from the site as of May 8.

The container ship was reportedly chartered by shipping company Maersk and was carrying customer cargo when the incident occurred. However, no Maersk crew or personnel were on board the vessel at the time of the crash.

The Dali was reportedly not being piloted by its own crew, but by local pilots who are used specifically to avoid accidents like the one that occurred. The pilots typically get on board just outside of local channels and take the ships into ports.

The NTSB was on the scene to lead the investigation into the collapse. At a press conference that day, NTSB Chair Jennifer Homendy said they believe that voyager data will play a critical role in the investigation.

A team of 24 experts planned to dig into nautical operations, vessel operations, safety history records, owners, operators, company policy and any sort of safety management systems or programs.

Following the collapse, engineers reportedly began working to remove the first pieces of the bridge as an investigation continued into what factors caused the fatal incident.

Homendy reported at the time that the vessel had 56 containers on board of corrosive flammable material and batteries, adding that some of the containers were breached. One of the materials was sheen, which is used in paint, and that has leaked into the Patapsco River.

NTSB officials had also boarded the vessel to obtain its black box, which provided an initial timeline of events through voyage data recorder information. “Numerous aural alarms were recorded on the ships’ bridge audio,” the NTSB initially found.

Preliminary Findings

At the time of impact, an apprentice pilot was controlling the ship under the guidance of a senior pilot. When the pilots boarded, the captain reported the ship was in good working order, according to the report.

NTSB investigators said the crewmembers tested negative for drugs and alcohol, and the fuel tested negative for contaminants three times. About 10 hours prior to the incident, while the ship was still moored in the Baltimore port, it experienced two onboard blackouts, one caused by a crew error, according to the report.

“The NTSB is still investigating the electrical configuration following the first in-port blackout and potential impacts on the events during the accident voyage,” the report stated.

The report does not include a probable cause, which will be part of the final report that can take up to two years to complete.

The NTSB says it will continue evaluating the design and operation of the Dali’s power distribution system (including its breakers). Examination of damage to the vessel will also continue when the ship is clear of debris and moved to a shoreside facility.

“The NTSB is working with parties to immediately assess their bridges and determine whether pier protection needs to be improved. Specifically, the MDTA is studying short-term and long-term options for upgrades to the existing protection system for the eastbound and westbound spans on the Gov. William Preston Lane Jr. Memorial Bridge (commonly known as the Bay Bridge) near Annapolis,” wrote the board.

“The NTSB is examining the pier protection improvements that have been made on the following bridge collapses resulting from marine vessel strikes that the NTSB has investigated: the Sunshine Skyway Bridge in Tampa Bay, Florida; Queen Elizabeth Causeway Bridge near South Padre Island, Texas; and the I-40 Bridge near Webbers Falls, Oklahoma.”

The full preliminary report can be found here.


Tagged categories: Accidents; Bridges; Bridges; Fatalities; Health & Safety; Infrastructure; Infrastructure; NA; North America; NTSB (National Transportation Safety Board); Port Infrastructure; Program/Project Management

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