Richard Spencer at the Telegraph - Chinese navy did not know submarine was missing:
The Chinese navy was unaware that one of its submarines was in trouble until a fisherman spotted the vessel's periscope sticking out of the water close to an offshore island.That must have been a heck of a 911 call.
It is not clear how long the accident happened before the vessel was discovered by the fisherman, but the fact that the navy did not know one of its submarines was missing is an additional humiliation for a military unused to the glare of publicity.Mistakes will always happen, but we're talking a technology that is a century old.
Around 70 sailors on board the vessel, the crew plus 14 observers, were found suffocated "at their posts", victims of a sudden mechanical malfunction that may have been caused by human error, navy sources quoted on the internet said.
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On state television on Monday night, President Hu Jintao, and Jiang Zemin, his predecessor who is still head of the central military commission and commander-in-chief, were seen touring the boat and meeting relatives of the dead.
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"Sources said they were not discounting the possibility that a crew member may have mistaken an exhaust valve for an intake valve resulting in the suffocation of the entire crew," it said, without explaining how this could happen.
Another theory is that a chemical leak "perhaps caused by battery fluid mixing with seawater" might have affected the ship.
A third, from a Hong Kong defence specialist quoted by the South China Morning Post suggested that a new diesel engine was undergoing tests.
Diesel-powered submarines are supposed to switch off their engines during a dive and run on batteries, and if this procedure failed, the crew's oxygen could have been used up.
