A loose wire caused a power failure on the 300 metre cargo ship Dali, leading to its collision with Baltimore's Francis Scott Key Bridge that killed six construction workers and destroyed the span.

The National Transportation Safety Board investigation found a single loose wire in the electrical system caused a breaker to unexpectedly open, launching a sequence of events that led to two vessel blackouts and a loss of propulsion and steering.

Wire-label banding prevented the wire from being fully inserted, causing an inadequate connection, the NTSB said in its final conclusions on the cause of the accident in March 2024.

NTSB Chair Jennifer Homendy compared the painstaking search for the wire to finding a single loose rivet on the Eiffel Tower.

The NTSB and the ship's manufacturer HD Hy

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