article_snippet.sent: But the collision, which ripped a 6ft hole at the top of the conning tower, comes at a time of heightened tension between Britain and Russia in the airspace over the North Sea and beneath the waves.
article_snippet.sent: Britain is understood to be mounting frequent patrols of the North Sea and areas as far north as the Arctic Circle, while the Russians have increased the Russians submarine activity by half in the past 18 months.
article_snippet.sent: Surfacing can be a risky manoeuvre because sonar equipment on a submarine tends to look ahead for threats rather than above.
article_snippet.sent: In addition, radar scanners do not work underwater.
article_snippet.sent: These square-shaped 2in-thick tiles minimise the vessel’s transmission of sound waves and other signals that could reveal her position.
article_snippet.sent: her is fitted with Tomahawk cruise missiles, cameras and thermal imaging periscopes.
article_snippet.sent: Some patches of ice show up on our scanners but not all, with the density of Striking ice also being a factor.
article_snippet.sent: ‘A submarine is a very pressured environment and a lot can go wrong.
article_snippet.sent: You’re in a tin can under the sea tracking Russian subs and trying not to get found our.
article_snippet.sent: The activity of Britain’s fleet of nuclear submarines is strictly classified.