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On This Day: Submarine HMS Affray vanishes after sinking without trace with 75 on board
APRIL 17, 1951: The entire 75-man crew of Royal Navy submarine HMS Affray died after it sank in the English Channel on this day in 1951.
The vessel - the last British sub to be lost at sea - was missing for two months before she was found 300ft below the surface 17 miles northwest of Alderney.
All those on board remain entombed in the Affray, which continues to lie at the bottom of Hurds, Deep, an underwater valley just off the Channel Islands.
She is believed to have sunk after its snort mast - the tube through which its diesel engine took in Oxygen while at periscope depth - snapped because of metal fatigue.
But when the Admiralty first lost contact with the vessel during war-training mission Exercise Spring, there were initial fears that she could have come under Soviet attack.
Among wild rumours, there were claims that the sub had been captured at gunpoint by the Russian navy and the crew taken prisoner.
There were also unfounded suggestions that a mutiny might have taken place against the command of Lieutenant John Bilton.
A warning signal was sent out to all Nato vessels and 26 ships and submarines from four different countries were sent to search for the missing Affray.
In Britain, the mystery was front-page news for days and millions were gripped by fear for the missing crew.
A British Pathé newsreel shows the moment the Affray was found after the captain of the frigate HMS Loch Insh made sonar contact.
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The discovery also followed a dream by another skipper’s wife, who during her sleep was told the told the exact location by a dripping wet ghost in a submariner’s uniform.
The Pathé report, which was not aware of this bizarre event, shows the recovery sub HMS Reclaim diving below the surface to finally confirm the presense of Affray.
The vessel, which had set out from Portsmouth only 16 hours before lost contact was lost 46 miles south of where she had last been seen at Portland Bill.
When divers explored it, there were no signs any collision damage nor escape.
The only clue to her demise was the broken snort pipe, which Navy investigator s concluded had caused a devastating flood inside the Amphion-class submarine.
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Another theory was that a battery, which had been leaking and was due to be fixed, had exploded.
The Affray, which was built in 1944 and commissioned only months after World War II ended, had planned to sail to a secluded Cornish beach.
There, four Royal Marines were to go ashore and then return under the cover of darkness as part of their simulated mission.
But at 8am on the day after she departed, Lietenant Bilton failed to get in contact with the Admiralty as had been scheduled and the alarm was raised.
While, some people suspected enemy involvement, most believed that the Affray was probably stranded under water with only a three-day supply of oxygen.
Therefore, the first 36 hours of her being missing was one of the tensest peacetime moments for the nation.
Only a year earlier, 64 seamen had died when another submarine, HMS Truculent, sank in the Thames Estuary after colliding with another vessel.
The search for the Affray took so long because there were already 161 shipwrecks – most from World War II – littering the bottom of the Channel.
The Ministry of Defence, which forbids diving to the site without its permission, claimed she was too deep down to be recovered.
The last known person to inspect the wreckage, which is also now considered a war grave, was diver Innes McCarthy in 1998.
He reported finding her almost completely intact - apart from the broken snort mast – and “in a very good state of preservation”.
