(WASHINGTON) — The National Transportation Safety Board (NTSB) on Wednesday released an initial timeline of events in the collapse of the Francis Scott Key Bridge in Baltimore, which was struck by the containership Dali early Tuesday morning.
Information recovered from the ship’s voyage data recorder (VDR) showed power failed for 1 minute and 3 seconds as the ship approached the bridge. The recorder, which officials said is “very basic” when compared to those on aircraft, stopped picking up sensor data during the outage but did record audio of the pilot giving steering commands and rudder orders.
The U.S. Coast Guard also confirmed Wednesday that the containership’s engines had undergone routine maintenance while in the Port of Baltimore. Dali was en route to Sri Lanka when the incident occurred.
NTSB timeline of events
00:39 – VDR recorded the ship’s departure from the Seagirt Marine Terminal.
01:07 – Ship had entered the Fort McHenry Channel.
01:24 – Ship was on a true heading of approximately 141 degrees at a speed of 8 knots.
01:24:59 – Numerous alarms are recorded on the ship’s bridge audio. At same time, the VDR stopped recording sensor data, but continued to record audio using a redundant power source.
01:26:02 – VDR sensor data recording resumed. Steering commands and rudder orders were recorded on the audio during the gap time.
01:26:39 – The pilot made a general VHF call for tugboats in the vicinity to assist. At the same time, a dispatcher phoned the Maryland Transport Authority (MDTA) duty officer regarding the blackout.
01:27:04 – The pilot ordered crew to drop the port anchor and issued additional steering commands.
01:27:25 – The pilot issued a call over VHF radio reporting Dali had lost all power and was heading toward the bridge. At about this time, MDTA data shows the duty officer radioed agency units that were already on scene due to construction on the bridge – one on each side – and ordered them to close the traffic on the bridge. All lanes were then shut down by the MDTA.
01:29 – The ship’s speed was just under 7 knots.
01:29 to 01:29:33 – The ship’s audio recorded the impact with the bridge.
01:29:39 – The pilot reported the bridge down over VHF radio.
The NTSB began interviewing crewmembers Wednesday, according to agency Chairwoman Jennifer Homendy. The first interviews with the two pilots aboard were scheduled for Thursday.
Homendy said that some of the containers on Dali’s bow were breached during the incident, including some with hazardous materials. A sheen has been detected near the ship, and although the composition is not known, the hazardous cargo aboard was reportedly mostly corrosives and flammables.