NTSB Identifies Electrical Failure as Cause of Baltimore Bridge Collapse

The National Transportation Safety Board (NTSB) has determined that a loose electrical wire caused the cargo ship Dali to lose propulsion and steering, leading to its collision with Baltimore's Francis Scott Key Bridge on March 26, 2024. The impact resulted in the bridge's collapse and the deaths of six construction workers.

During a hearing in Washington, the NTSB approved findings and recommendations aimed at preventing similar incidents. Investigators identified a single loose wire among thousands on the Dali; a mispositioned label had prevented it from being fully inserted into its terminal. This electrical failure led to two power blackouts as the vessel approached the bridge.

Board member Michael Graham noted that the crew's response was timely and appropriate given the circumstances. He emphasized the need for the maritime industry to enhance safety systems and risk management, aligning more closely with aviation standards.

The NTSB also highlighted the absence of countermeasures to reduce the bridge's vulnerability to ship collisions. A vulnerability assessment, as recommended by the American Association of State Highway and Transportation Authorities, had not been conducted by the Maryland Transportation Authority. Additionally, the lack of effective communication to alert highway workers contributed to the fatalities.

The Dali, a Singapore-flagged vessel, experienced two power blackouts during its departure from Baltimore. The first blackout was resolved, but the second occurred due to a fuel supply issue, requiring manual intervention in complete darkness. Investigators suggested that infrared thermal imaging inspections could have detected the loose wire beforehand.

NTSB Chair Jennifer Homendy stated that the tragedy was preventable and emphasized the importance of proactive safety measures. The board expressed frustration with the response from the ship's operator, Synergy, and manufacturer, Hyundai Heavy Industry, for not implementing recommended changes.

Maryland officials have revised the estimated cost for replacing the bridge to between $4.3 billion and $5.2 billion, with completion now projected for 2030. U.S. Transportation Secretary Sean Duffy criticized the project's management, stressing the need for efficient use of taxpayer dollars.