At approximately 10 p.m. on Monday, December 23, the Aberdeen Coastguard were alerted by the oil platform Marnock of a Mayday broadcast from the motor tanker Bertora. The 55,756-grt vessel, which measures 230 m, was located approximately 130 miles east of Peterhead when its engines failed. The vessel's master broadcast a distress call on the distress frequency, which was ultimately received by the rig standby vessel Viking Protector, which then relayed the call to the oil platform - contacting the Aberdeen Coastguard. Upon examination, it was deemed that the cause of the engine failure was the result of a safety pin in the oil fuel line that had failed and cut off all fuel to the engine.