Decorated commander of Royal Navy warship used to protect British waters from Russian vessels jailed following drunken sex assault on junior sailor

Published: 12:08 EDT, 5 November 2026 | Updated: 12:24 EDT, 5 November 2026 The commanding officer of a Royal Navy warship used to protect British waters from Russian submarines has been jailed following a drunken sexual assault on a junior officer.Lieutenant Commander Martyn Mayger claimed he was teasing the younger sailor about his weight when he touched his backside and put his hands on his hips on his first day in charge of the warship.However his victim raised a complaint about the incident which came after sailors had been drinking at a whisky distillery in the Shetland Islands.Mayger, 40, was marched off HMS Tyne within days of taking charge of the river-class offshore patrol ship and accused of two sexual assaults following the incident on May 10 2025.He was convicted of one sexual assault following a court martial trial at the Military Court Centre at Catterick Garrison, North Yorks, earlier this year.Returning to the Military Court Centre for sentencing on Thursday, Mayger was sent to prison for four months.The former Lt Cdr looked stunned as Judge Advocate Tom Mitchell told him it was an ‘exceptional case’ requiring immediate custody.‘Over and above the fact that you were the captain of a ship, this happened on your first night out at the end of your first command,’ he said. Lt Cdr Martyn Mayger (right) when it was announced he was to take charge of HMS Tyne in 2025 HMS Tyne is one of the busiest vessels in the Navy's fleet and helps to safeguard Britain's interests and has been operational since 2003‘This was a dereliction of your duty and the standards you were enforcing against others.’He added: ‘The ship was alongside and therefore not on operational duties, but this offence had an operational effect because within hours the ship found itself absent of its Commanding Officer.‘Offending of this kind by the captain of a ship against a junior officer would be considered by many to be unthinkable, and yet here we are.’Describing the offence, he said: ‘You groped him once, stepped back and said, “you didn't like that did you?” Then you groped him again the same way.‘You accepted touching his bottom but denied that it was sexual.‘Sexual offending undermines the bond of trust among those who serve together.’The trial heard that Mayger and others had been onshore in Lerwick while the Tyne's crew enjoyed what was termed a ‘lazy weekend’ when they were not on active manoeuvres.The party visited pubs and a whisky distillery before returning to the ship's wardroom, or private mess, where Mayger entertained the junior officers.Mayger, who was drunk, argued that while he acted inappropriately for his position he was not acting sexually and the touching was horseplay while making fun of his victim's size.He was asked whether he was gay and said he was not, having had a relationship with a woman in the past.Natalie Turner, mitigating, said the conviction has had a devastating impact on Mayger.She said: ‘The Royal Navy has been the central focus of his life since the age of 14 when he joined the cadets.'He says himself: “This is not simply my employment. Since becoming a sea cadet it has shaped every aspect of my life.”‘The loss of this role would be personally and professionally devastating.’While leading the UK's sea support for Ukraine, Mayger advised ministers and was in charge of 100 deployed personnel and a £100m budget.HMS Tyne is described as one of the busiest vessels in the Royal Navy fleet patrolling British waters.In January 2025, Tyne was reported to be monitoring Russian spy ship Yantar in the North Sea along with HMS Somerset.And in July 2026 it shadowed the Russian frigate Neustrashimy when the latter conducted a live fire exercise 40 miles off Plymouth.