Loose wire caused cargo ship to crash into Francis Scott Key Bridge, NTSB finds

The incident occurred in March 2024, when the Dali lost power and struck a support pier of the bridge, causing sections of the span to fall into the Patapsco River. The NTSB’s final report determined that a misinstalled wire led to a total power loss, leaving the ship without propulsion or steering before the collision.

"The National Transportation Safety Board determines that the probable cause of the contact of the container ship Dali with the Francis Scott Key Bridge was a loss of electrical power blackout due to a loose signal wire connection to a terminal block stemming from the improper installation of wireless label banding," the board determined.

The board also placed blame on the Maryland Transportation Authority for failing to assess the bridge’s vulnerability to a ship strike, noting that the disaster could have been prevented if prior safety recommendations had been followed.

According to Fox News, investigators said the crew reacted fast but had too little time to restore power before the vessel struck the bridge. The report said the collision was unavoidable due to the proximity of the ship to the span and the delays in restraining its systems. The NTSB criticized the MDTA for not conducting a vulnerability assessment recommended by the American Association of State Highway and Transportation Officials, which could have identified ways to protect the bridge from ship impacts.

The board also faulted Synergy, the ship’s operator, for allowing critical electrical systems to run in manual mode, which hindered recovery efforts.

"Staff found that Synergy operational oversight was inadequate because it did not discontinue crew's ongoing use of the flushing pump as a service pump for the diesel generators aboard the Dali, and at least one other vessel," NTSB engineer Bart Barnum said.

The findings come a day after Maryland officials announced that they would rebuild the Francis Scott Key Bridge. The rebuild, however, is now expected to take two years longer than initially expected and will cost twice the original estimate. The project will not be completed until 2030 and could cost as much as $5.2 billion.