Following the tragic collapse that claimed the lives of six roadwork crew members, the investigation by the board commenced promptly.
Chair Jennifer Homendy reported that investigators boarded the vessel to document the scene, retrieve evidence like the ship’s data recorder and engine room details, and conduct interviews with the captain and crew.
Homendy emphasized during a news briefing shortly after the incident that their mission was to understand why and how it happened and to prevent such disasters in the future.
The preliminary report outlined that around 1:25 a.m. on March 26, when the Dali was about half a mile from the bridge, a key electrical breaker malfunctioned, causing a blackout by cutting power to the ship’s equipment.
This blackout led to the shutdown of the main engine, and subsequent power restoration efforts were made, including dropping anchor and requesting tugboat assistance.
Unfortunately, a second blackout occurred, prompting a marine radio warning to other vessels, but the ship ultimately struck a main bridge support pier, resulting in its collapse.
Despite issuing a mayday alert, tragically, the warning came too late to save the bridge workers. The recovery of the victims’ bodies concluded last week.
A controlled demolition was executed on Monday to dismantle the remaining part of the collapsed bridge, a critical step to free the grounded Dali container ship.
The board’s preliminary report, released on Tuesday, represents only a portion of the findings expected in the final report, which is anticipated to take over a year to complete.
Fuel testing did not raise concerns about its quality, as per the preliminary report.
Additionally, the FBI has initiated a criminal investigation into the circumstances leading up to the collapse.
Homendy affirmed that the investigation would comprehensively examine all aspects of the crash, focusing on the ship’s power loss and whether similar issues had occurred before.
They also planned to review relevant policies, training practices, and the bridge’s design, engineering, and condition.
The National Transportation Safety Board’s inquiry will extend to the ship’s electrical system in general, including the engine room and circuit breakers, which are expected to yield crucial insights.
Marcel Muise, the safety board’s lead investigator, outlined a preliminary timeline based on the voyage data recorder, indicating that a comprehensive analysis of the entire recording was underway to develop a detailed transcript of events leading up to the collapse.
