In an update on its preliminary investigations into what may have caused the Dali containership to collide with the Francis Scott Key Bridge in Baltimore on 26 March, the US National Transport Safety Board (NTSB) has given initial information on the timeline of events leading up to the catastrophic incident – including the vessel’s power outage – as provided by the recovered voyage data recorder.
In a second media briefing, NTSB Chair Jennifer Homendy said the investigation is still very much in the information gathering phase. ‘We are not analysing the information we are collecting, we are collating the perishable evidence,’ she said.
Teams from the NTSB have now been onboard the ship, along with representatives from the US Coast Guard, the Maryland Transport Authority, the Association of Maryland Pilots and from the ship’s owner, Grace Ocean, and the ship manager, Synergy Marine.
Homendy confirmed that there were 21 crew members onboard the Dali, along with two pilots,
The NTSB has had access to the cargo manifest, which indicates that 56 containers onboard contain hazardous materials, some of which were flammable and corrosive, and include lithium-ion batteries. According to Homendy a sheen has also been detected on the water surround the vessel.
An NTSB engineering team has been documenting the design and operation of the vessel’s onboard systems, including propulsion, steering and power.
There has been a walk-through the bridge and engine room areas of the Dali, and interviews are also underway with the crew onboard.
Some six hours of data from the VDR has been recovered for analysis, covering the period been 12.00 and 6.00 am. The quality of the data varies widely, said the NTSB, and work will be undertaken to see if background noise, etc can be eliminated. However, information has been retrieved on ship speed, engine RPM, heading, and rudder angle.
According to the VDR, the vessel entered the channel at 1:07 and was travelling at around 8 knots.
At 1:24, there were audible alarms on the bridge and the data sensors stopped recording. At 1.:26, the data sensors started recording again, and a pilot gave the order to drop the fore anchor.
At 1:27, there was a pilot VHS radio call reporting the loss of all power and requesting the closure of the bridge to traffic.
Homendy emphasised that the VDR is a ‘basic system’ and can only provide ‘a snapshot of the major systems on a vessel.’
While investigators are currently working on six hours of information from the VDR, Homendy said that 30 days’ worth of information on vessel operations prior to the collision should be accessible to them. She also told reporters that a preliminary report on the incident should be available in 2-4 weeks.
In response to questions, Homendy said that the NTSB is aware of reports suggesting that the Dali had suffered previous power outages, and these will come within the scope of its investigation. She noted that the pilots onboard the vessel had still to be interviewed, but discussions had already taken place with the chief engineer.
Asked about media speculation about contamination of the ship’s bunker fuel, Homendy said the investigation will be completely facts-based.
Noting that the fuel onboard was marine diesel oil (MDO), she said that ‘We look at the fuel system, we collect a sample of the fuel … and we will analyse quality, any sort of contamination, viscosity – it will all be a part of the investigation.
‘We have data that is consistent with a power outage, but we don’t have factual information that can confirm that power outage,’ she commented. ‘We are just looking for more information on the ship.’
Theories over contaminated fuel being a cause of the power outage continue to abound.
In terms of the vessel’s bunkering history on its current voyage, maritime technology company FuelTrust has suggested that the Dali had previously refuelled in Shanghai and then Korea, before transiting the Panama Canal. The company also reported that the Dali had bunkered fuel in Baltimore, although this stem would have been stored in a settling tank and still be awaiting testing lab results. The vessel is reported to be carrying 1.5 million gallons of bunker fuel onboard.
AMERICAS: NTSB launches investigation into Baltimore bridge disaster