The American sub was performing a routine pre-dawn patrol when seamen heard a “thump”, according to a Navy source who spoke to several news agencies. The crew tried to ascertain the damage by looking into its periscope, only to realize it was no longer working. The other periscope on the submarine revealed that the first one had been “sheared off”.
It appears the ‘fishing trawler’ that collided with the 7,000-tonne submarine was not only undamaged, but barely noticed the accident.
“The vessel continued on a consistent course and speed, offering no indication of distress or acknowledgement of a collision,” says an official statement published on the US Navy website.