Isle of Skye grounding

When a tanker ran aground on the west coast of Scotland, accident investigators found that Key Bora’s crew had been relying on inaccurate chart data. 

When a tanker ran aground on the west coast of Scotland, accident investigators found that Key Bora’s crew had been relying on inaccurate chart data. 

In March 2020, the 92m (300ft) chemical tanker Key Bora ran aground on its approach to the Kyleakin pier, on the Isle of Skye, Scotland. Its hull was holed and floodwater entered its empty ballast tanks. No one was injured and no pollution occurred. 

When the Key Bora had been three nautical miles out from the pier, the master reduced the vessel’s speed to four knots. Ten minutes later, as the vessel approached a buoy marking the Black Eye Rock, the ship’s speed was reduced by another two knots. The master was then warned that the Key Bora was passing very close to the buoy, but he assessed that the vessel was well clear of the rock and continued his approach to the pier, now 400m away.  

He was then forced to make a series of course alterations to counter the unexpectedly strong tidal stream and alerted to a 4.9m (16ft) charted depth point showing up on the ECDIS (Electronic Chart Display and Information System), close to the pier. Having calculated that the vessel’s draught was around 6.2m (20ft), the master pointed to the echo sounder, showing 7.0m (23ft) of water, and said he was content to continue with the manoeuvre. 

The grounding

Moments later, just 50m (164ft) from the pier, Key Bora shuddered and came to a stop. Realising that his vessel was now aground, the master tried to manoeuvre the ship clear of the obstruction using the engines, rudder and bow thruster, but without success. The crew then discovered water rising in one of the ballast tanks which had previously been empty.  

The ship was refloated twelve minutes later and berthed at the pier under its own power. A diver inspection next day revealed damage to the hull, including shell plating ruptures. Once its cargo was fully discharged, Key Bora was sailed to a dry dock for repairs in Glasgow's Greenock. 

2 Key Bora MarineTraffic
Credit: MarineTraffic

Passage plan

When the 4.9m charted depth point was first observed, the master and chief officer had compared the ECDIS information with a local survey chart and photocopied extract of the relevant Admiralty chart given to them by the ship’s agent — neither of which showed the 4.9m feature. The master believed that the information from the agent had come from a trusted source, and that it appeared to be accurate and current.  

Unfortunately, neither man had checked the update status of the electronic navigation system. They were, therefore, unaware that the 4.9m obstruction had been downloaded into Key Bora’s ECDIS, as a UK Hydrographic Office correction, just eight days earlier.  

Post-accident surveys of the approaches to the pier revealed the presence of a large granite boulder, around 3m (10ft) in length, protruding 1.9m (6ft) above the surrounding seabed, in the location where the Key Bora grounded. It has since been removed.

Accident report

An accident investigation by the UK’s MAIB (Marine Accident Investigation Branch) has concluded that the Key Bora ran aground because the passage plan for the approach to the pier was based on inaccurate survey and tidal stream data. It also found that the ECDIS had not been used properly, and that no action had been taken aboard the ship to abort the manoeuvre despite indications that the conditions encountered were not as expected. 

The report also identified weaknesses in the safety management of the Kyleakin pier, owned and operated by MOWI Scotland Limited — the world’s largest producer of Atlantic salmon. The site, it says, was not being operated in accordance with the Port Marine Safety Code and no marine safety management system was in place — two conditions which had been put forward as mitigation measures by MOWI in its planning application to build the pier.

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MAIB illustration of grounding. Credit: MAIB

Previous incidents reported by MAIB

In September 2019, the chemical tanker Key West, ran aground on the Black Eye Rock while approaching the Kyleakin pier. The MAIB found that the master was forced to abort the approach as nobody was on hand ashore to take the mooring lines. After an assurance that staff would be available to assist with a second attempt, Key West’s master tried again but, with just 400m (1,300ft) to run, the same problem arose. The master had to go astern and, as the ship decelerated, it was swept by the strong tidal stream onto the Black Eye Rock. 

In February 2020, a MOWI aquaculture worker was killed while trying to climb onto a feed barge from a workboat when he fell into the water and was crushed between the vessels.  

The MAIB concluded that the transfer had not been properly planned or briefed and was not adequately controlled. There were also no risk assessments or procedures in place for the transfer of personnel between aquaculture installations and boats.  

Read the full MAIB Key Bora accident investigation report.  


Dennis O’Neill is a freelance journalist specialising in maritime.