BALTIMORE– Investigators investigating the March collapse of Baltimore’s Francis Scott Key Bridge said in a preliminary report Tuesday that the freighter Dali experienced a power outage about 10 hours before it left the Port of Baltimore during maintenance work.
The outage was caused when a crew member accidentally closed an exhaust muffler, causing the ship’s engine to shut down, the National Transportation Safety Board report said. The ship lost power again and crashed into one of the bridge’s support columns shortly after leaving port on March 26, causing the bridge to collapse within seconds.
A full investigation could take a year or more, the agency said.
The board launched its investigation almost immediately after the March 26 collapse that left six members of a roadwork crew dead. Investigators boarded the ship to document the scene and collect evidence, including the ship’s data recorder and information from the engine room, said board chair Jennifer Homendy. Investigators also interviewed the captain and crew members.
“Our mission is to determine why something happened, how it happened and to prevent it from happening again,” Homendy said at a news conference days after the disaster.
The bridge collapsed within seconds after the freighter Dali lost power and hit one of the supporting columns. The ship, which was headed from Baltimore to Sri Lanka, issued an emergency warning with just enough time for police to stop traffic but not enough to rescue workers filling holes in the bridge.
The last bodies of the victims were recovered last week.
On Monday, crews conducted a controlled demolition to demolish the largest remaining span of the collapsed Francis Scott Key Bridge, a key step in freeing the grounded container ship Dali.
The board’s preliminary report released Tuesday is likely to include a fraction of the findings that will be presented in the final report, which is expected to take more than a year to complete.
The FBI has also launched a criminal investigation into the circumstances that led to the collapse.