How To Escape From A Submarine (and other things I learnt this weekend)
My parents, my son and I spent yesterday morning on a guided tour of Fort Blockhouse, formerly HMS Dolphin, home of Britain’s submarine fleet until 1994. Parts of the site, in Gosport, Hampshire, date back to the 15th century and, although you can still see some of the original defences, much of it was updated and altered in the 19th century (to protect Portsmouth Harbour from a French invasion that never came) and then again during the Second World War (this time to protect the harbour from a German invasion that never arrived.)
Much of the sprawling waterfront site is made up of ugly post-war buildings (the MOD (and its predecessors) doesn’t need normal planning permissions…) but it was a fascinating tour and part of the excellent Heritage Open Days scheme which happens at the same time every year and sees hundreds of sites not normally open to the public accessible for a weekend in September.
Highlight of the tour was a guided tour of the base’s Submarine Escape Training Tower which dominates the skyline and can be seen from miles around. Formerly used by the Royal Navy to train submariners in how to escape from the stricken submarine, it is now no longer in use, due to that 21st century hazard – health and safety!
It seems a risk assessment decided that sailors were more likely to be injured or killed training to escape from a submarine than the chances of them being involved in a real incident which leads to fatalities. It seems rather daft, but I suppose there is some logic to it.
Our tour took us below the the 100-foot water tank – which takes 18 hours to fill up (a procedure that results in a drop in water pressure for residents of the town of Gosport) to experience the claustrophobic atmosphere men would have faced in an emergency situation (although there were only 20 of us in a tiny watertight compartment when the reality was likely to be more like 60).
We were told the faster way of submarine escape has a higher risk of sailors getting the bends (through too rapid decompression). But the safer method had drawbacks too – it took four minutes for each person to get out meaning that even with just 60 personnel, the whole procedure would take four hours. As tradition would have it, the captain would be last out (although wounded men would be behind even him if their injuries ran the risk of blocking the escape hatch or killing them try to get out…)
With the advance of technology, these days the policy is to send down another submarine to rescue stricken crew and all sorts of technology (including ‘oxygen’ candles) are used to keep people alive when rescuers plan what to do.
We then took a lift to the top of the tower and peered down to the bottom – where we’d just been stood (below hundreds of tonnes of water, prevented from leaking by a rubber seal!). Our guide then demonstrated the survival suits and individual life-rafts (or rather an old version) which would hopefully save submariners once they’d successfully exited their stricken sub.
He gave me permission to post the video clip below (you may wish to scroll to about a minute in). In fact, despite having been told not to take pictures of the Fort Blockhouse buildings themselves (a little bizarre in the the age of Google Maps but something I adhered to (the first and third pictures on this blog are sourced from the internet)), we were told we were welcome to take pictures in the tower as none of it was secret. Indeed representatives of both the Russian and Chinese navies have been to the site and had been provided with briefings on its construction. It seems when it comes to accidents involving submarines, rivals – even ‘enemies’ – are prepared to aid and assist each other.