Plenty of sailors can boast a proud maritime pedigree, but none possesses the unique family history of HMS Turbulent crew member Lt Patrick Ryan.

The officer is believed to be the first fourth-generation submariner in the Royal Navy, following his father, grandfather and great-grandfather into the Silent Service.

The Casing Officer of the Devonport-based T-boat earned his dolphins last year – but with nine decades of submarine service preceding him, there was really only one branch of the Navy that he could join.

Ted Ryan set the trend for the family in 1909 when he joined HMS A9.

He later commanded submarines B5, C3, D1 and E26 before being lost in the latter vessel when she was believed to have been sunk by a mine in 1916.

A generation later, Lt Pat Ryan also joined the ‘trade’, serving in H51, L26, Salmon and Trident – the latter as her First Lieutenant.

He then joined the doomed HMS Thetis during her sea trials, and was one of the 99 men who died when the boat went down in Liverpool Bay on the eve of World War II.

The third generation of the family to earn dolphins was represented by Cdr Paddy Ryan, who joined the Submarine Service in 1959 and stayed with it for 31 years, commanding four boats including Polaris-armed HMS Renown.

The latest Ryan to wear his dolphins gives the family a unique place in the Submarine Service says Cdr Jeff Tall, director of the RN Submarine Museum in Gosport and a close friend of Paddy Ryan Snr.

And the museum should know as it has the most comprehensive archive of personal files on ‘deeps’ of anywhere in the country.

“Every submariner wears his dolphins with pride – and Patrick is as aware as anyone of the proud history of the Submarine Service,” said Cdr Tall.

“He is unique as the only fourth-generation submarine officer in the world.

“No other family can claim to have served in 17 classes of submarine – that’s just under half of all the major classes in the RN submarine arm – and commanded eight of them.”

There’s more than just the Ryan name which continues to flourish in the Silent Service; so too does the ceremony which initiates a sailor into the branch.

Like his predecessors, Lt Patrick Ryan caught his dolphins between his teeth from the bottom of the glass as he knocked back a tot of rum.