Devonport Workers Entombed in Submarine Ballast Tank

 

Colleagues had mistakenly sealed the tank at Devonport base in Plymouth, where Britain's nuclear submarines are refitted. The desperate electricians hammered on the tank with a drill and were saved when they got a faint signal on a mobile phone.

 

The incident at Devonport Naval Base in Plymouth which saw the men accidentally sealed in by colleagues has been described as "extremely unpleasant". 

 

A report said the submarine was in dry dock last December and the two men were checking sonar gear inside the ballast tank. When they tried to leave they found a seal had been placed over the entrance in preparation for an air tightness test.

 

A report reads: "In an attempt to raise the alarm they used the only thing they had to hand - a battery powered drill to hammer against the tank boundary but to no avail. There was no-one in the dock bottom to hear them. They switched on their mobile phones but there was no signal at the bottom of the tank so they progressively climbed to the upper reaches of the tank until fortunately one phone managed to get a one bar signal."

 

The men were trapped for 20 minutes and were said to be "shaken but unhurt".