Workers face a “very complicated” task of righting a vessel which toppled over while in drydock, a marine expert said as investigations into the incident continue.
Two huge cranes have been placed next to US Navy vessel the Petrel, which tipped to a 45-degree angle last month, leaving 35 people injured.
The incident sparked a huge emergency service operation at the drydock in Leith, Edinburgh, which is operated by Dales Marine Services.
Iraklis Lazakis, of the University of Strathclyde, said the two cranes are at the vessel’s port side but “no other specific action can be speculated on about righting the vessel”, which he said would be a “very complicated procedure”.
Police remain at the scene, and on Thursday a police car could be seen as workers operated the cranes and moved around the stricken 3,371-tonne vessel.
Both the Health and Safety Executive (HSE) and Police Scotland said investigations into the incident, which happened on March 22, are continuing.
Read More: More than 20 people injured after ship topples over at Leith drydock
An HSE spokesman said: “Specialist inspectors from HSE are assessing the technical aspects of the structural collapse and continue to work with Police Scotland on the investigation into this incident.”
Dr Lazakis, of the Department of Naval Architecture, Ocean and Marine Engineering, said for the ship to be put upright a number of aspects need to be considered, including “the potential damage on the outer hull of the vessel on the starboard side, any internal structural damages or otherwise, any transfer of loads internally, and any movements of the keel blocks due to the shifting of the ship”.
He added: “One would also need to consider the lifting capacity/radius and angle of lift of the cranes in relation to the ship’s lightweight – or lightship – as well as any additional weights or loads within the ship.
“Another way to bring the ship up would be by initially assessing its structural condition externally and internally and shifting of loads etc, as well as performing any repairs needed on the outer hull, repositioning the keel blocks in the drydock if needed as per the ship’s docking plan, then starting to flood the drydock very slowly and tilting the vessel upright gradually.
Read More: Serious incident at Leith's Imperial Dock as ship topples over
“Overall, this is a very complicated procedure, also considering that, as I understand it, the drydock is used by another vessel I believe.
“I cannot speculate on how long this would take as there are so many unknowns at the moment.”
The 76m-long Petrel was once owned by the late Microsoft co-founder Paul Allen, who bought the ship to locate historically significant shipwrecks and discovered 30 sunken warships, including the Japanese Imperial Navy’s IJN Musashi.
But in 2022 the Isle of Man-registered vessel was sold to the US Navy, and is now operated by American-owned firm Oceaneering International.
The Petrel has been moored at Imperial Drydock in Leith since September 3, 2020 due to “operational challenges” from the pandemic.
Twenty-three people injured in the incident were taken to hospital and 12 were treated at the scene.
A Police Scotland spokesman said: “Officers are working with the Health and Safety Executive.
“Inquiries are ongoing to establish the full circumstances.”
In a statement on the Dales Marine Services website, it said it “continues to liaise with the emergency services and relevant authorities in dealing with the incident” and at this time it “cannot comment any further”.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules hereLast Updated:
Report this comment Cancel