A party of submarines was filmed partying during the coronavirus lockout, which sparked an investigation by the Royal Navy.
The captain of HMS Trenchant, a nuclear-powered attack submarine based at Devonport in Plymouth, was sent home on leave.
A video of the crew enjoying a party and a barbecue while the submarine was tied was shared on social media.
It shows sailors dancing and laughing, and a source confirmed that some drank alcohol.
HMS Trenchant was on patrol before having to return to Devonport for repairs.
The crew was to remain in solitary confinement while the repairs were completed.
BBC defense correspondent Jonathan Beale said it was understood that the captain had acted on the entertainment although he was informed that it could be inappropriate.
A Royal Navy spokesperson said, “An investigation is underway. It would be inappropriate to comment further. “