Glen Sannox ferry methane leak draws criticism of Scottish Transport Secretary

A significant release of approximately 700kg of highly flammable methane gas occurred aboard the CalMac ferry MV Glen Sannox on June 3, 2025. The incident, described as a “critical failure” in the vessel’s gas fuel system, happened while the ship was transporting 82 passengers between Arran and Troon. A faulty valve failed to its open position, causing the gas to vent while the vessel was underway.

Following the incident, Scottish Transport Secretary Stephen Flynn faced criticism from Liberal Democrat MSP Willie Rennie during a Scottish Parliament Transport Committee meeting. Rennie expressed concern that Flynn appeared unaware of the BBC report regarding the leak, despite previous promises of transparency. Flynn stated he had not been personally briefed but noted that details had been shared with the former cabinet secretary for transport in June 2025.

The ferry, which is the first UK-built ship capable of running on liquefied natural gas (LNG), utilizes propulsion systems from the Finnish firm Wartsila. Officials stated that the issue causing the leak has since been addressed through a “minor design modification,” a solution also applied to the sister ship, Glen Rosa.