Loose Cable on Cargo Ship Linked to Fatal Baltimore Bridge Collapse

Investigators have identified a loose cable as a potential cause of the Francis Scott Key Bridge collapse in Baltimore. This cable might have led to electrical issues on the Dali, the cargo ship that lost power and crashed into the bridge. The National Transportation Safety Board (NTSB) released documents on Wednesday detailing this discovery.

Electrical Issues and Power Outages

The Dali experienced its first power outage while still docked in Baltimore. A crew member mistakenly closed an exhaust damper during maintenance, causing one of the ship's diesel engines to stall. Following this incident, crew members altered the ship's electrical configuration, switching from one transformer and breaker system to another just before departure.

According to investigative reports, the loose cable was found in this second transformer and breaker system. Engineers from Hyundai, who manufactured the ship's electrical system, stated that this loose cable could create an open circuit, leading to a breaker opening. They simulated this scenario by disconnecting the cable, which resulted in a blackout on the ship.

Details from New Documents

The new documents released by the NTSB provide more insights into how the electrical system may have failed before the disaster. These records include various certificates issued after inspections of the Dali, confirming its general condition and compliance with maritime safety regulations. However, they do not contain any analysis or conclusions; these will be part of the board's final report.

"It's pretty clear that they think they've found an issue that could cause a blackout," said Tom Roth-Roffy, a former NTSB investigator specialising in maritime investigations. He noted that the loose cable was in a critical location within the electrical system.

Investigation and Findings

Safety investigators had previously released a preliminary report documenting power issues on the Dali before and after its departure from Baltimore. The new records offer more details about these problems in the moments leading up to the deadly crash. The Dali was en route to Sri Lanka when it lost steering due to power failure and collided with one of the bridge's supporting columns, destroying the 1.6-mile span and killing six roadwork crew members.

In April, Hyundai sent engineers from South Korea to assist with the investigation. They removed an electrical component called a terminal block for further testing. This component is used to connect electrical wires and was part of the system where the loose cable was found.

Maintenance and Crew Responsibility

Roth-Roffy mentioned that checking hundreds or thousands of wires is tedious and time-consuming. He added that various factors, including constant vibrations on a ship, could cause connections to loosen over time. "To say that this should have been detected is probably true but somewhat unrealistic," he said. "But the ship's crew has ultimate responsibility for the proper maintenance and operation of the ship."

The Dali left Baltimore for Virginia in late June for repairs. Local media reported last week that it would sail to China later this month.

The NTSB spokesperson declined to comment further as the investigation is ongoing. The final report will include analysis and conclusions based on these findings.