WASHINGTON, D.C. — On Tuesday morning, the National Transportation Safety Board (NTSB) met and heard presentations from several staff members on the investigation into the Dali crash into the Francis Scott Key Bridge in March 2024.
"The fact is, none of us should be here today," says Chair Jennifer Homendy. "This tragedy should have never occurred. Lives should have never been lost. As with all accidents that we investigate this was preventable."
The Board heard presentations about several aspects of the investigation into the crash.
"This was a complex, multi-modal investigation," Homendy says.
The Dali was equipped with an emergency generator, which was designed to kick in in the event of a loss of power, according to the staff presentations about the container ship.
Just four minutes before the crash, a breaker opened at around 1:25 am, and the Dali experienced a low-voltage blackout, causing the main engine to shut down and the propeller to stop 8 seconds later. The engine and the thurster remained off after this point.
This breaker was the focus of an engineering presentation, and it was found that a loose signal wire.
PREVIOUS REPORTING: Could a loose cable have caused the DALI power outage leading to Key Bridge crash?
That signal wire had its label placed on a part that made it difficult to connect the wire during the construction of the vessel, and "resulting in an inadequate connection."
While the company operating the vessel did require inspections of the switchboards, the NTSB found that it lacked practical guidance to checking all of the thousands of wires and terminal connections on a vessel.
"Locating a loose wire in the thousands of miles of wiring is like looking for a loose bolt in the Eiffel Tower," said Homendy in appreciation of the work of the engineering investigators.
The ship made contact with the bridge at 1:29:09 a.m.
Another issue brought up during the presentations was the problems investigators had with recovering data and audio from the ship's vessel data recorder (VDR), which is kind of like a black box for ships.
Several streams of data were not recorded during the blackouts on the ship, and the recorded bridge audio was "destructively mixed."
In discussing the bridge portion of the investigation, the findings released in March of this year were reiterated.
"If MDTA had calculated the Key Bridge vulnerability, MDTA would have been aware the risk of collapse was almost 30 times greater than the acceptable risk threshold," read one of the slides in the presentation.
This presentation also included a discussion of highway worker safety, and how the workers were not notified by MDTA police about the danger.
"However, there are no ANSI [American National Standards Institute] for highway workers to receive emergency information before or during dangerous or life-threatening events within work zones," said an NTSB staffer.
The NTSB staff said that the following were not found to be factors in the accident:
- Environmental or waterway conditions
- Vessel complement and mariner credentialing
- Impairment from alcohol or other drug use
- Fuel quality or fuel switchover
- Vessel's ability to get underway after in-port blackouts
- Bridge construction with non-redundant steel tension members
Following the presentations, the staffers took questions from the Board.
After several rounds of questions and answers, the Board heard the findings, probable cause, and recommendations.
The proposed probable cause was found to be the loss of power due to a loose wire, with some contributing factors.
There was discussion of an amendment to the probable cause, the proximity to the bridge, to emphasize that the crew worked in a timely manner to try to resolve the issue, and that they just didn't have time, which was added.
The Board voted to approve the amended probable cause.
An amendment was added to the findings, and to the recommendations.
"Identifying that one signal wire... and determining it was disconnected... was no small task," said Homendy in explanation of why these investigations take time.
The meeting concluded just before 2:30 p.m. The final report is expected to be released in a few weeks.