Since their warship is a minesweeper, the crew of HMS Bangor should be accustomed to loud bangs.
But the huge thud they heard in the waters off Bahrain on Thursday was another Royal Navy vessel crashing into theirs.
In a gaffe that could compromise UK operations in the Gulf at a crucial time, HMS Chiddingfold reversed into HMS Bangor, apparently after a mechanical failure.
The accident ripped a huge hole in the hull, which is constructed of glass reinforced plastic. There was internal damage but no injuries.
Navy sources suggested there was no timeline yet for when the vessel can return to frontline duties.
The accident ripped a huge hole in the hull, which is constructed of glass reinforced plastic (pictured)
Navy sources suggested there was no timeline yet for when the vessel can return to frontline duties
One said: ‘HMS Chiddingfold got stuck in reverse.
‘The understanding at the moment is when she was attempting to go astern, there was a malfunction.
‘The crew couldn’t alter her course so they were forced to look on helplessly as she careered into HMS Bangor’s rear quarter bow first.
‘Her interior was ripped apart too. The ship won’t be in action for a while.’
Bangor is one of the Royal Navy’s seven Sandown-class mine counter-measures vessels.
The ship plays an important role in ensuring the security of the UK and global trade routes. Pictured, damage aboard HMS Bangor after the crash
Her standard crew of 39 includes mine warfare specialists and mine clearance divers.
Ordinarily she is based at the Clyde naval base in Faslane, Scotland, but she has been on long-term deployment to the Gulf.
According to the Ministry of Defence, Bangor is equipped with SeaFox unmanned underwater vehicles that trawl the ocean floor searching for mines.
The ship plays an important role in ensuring the security of the UK and global trade routes.
International shipping has been targeted by Iran-backed Houthi rebels in Yemen, with around 30 cargo vessels and tankers being struck.
The attacks have continued despite UK and US air strikes on Houthi bases