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Nuclear Subs 'Collide In Ocean'
Jantastic noted a BBC report saying "A Royal Navy nuclear submarine was involved in a collision with a French nuclear sub in the middle of the Atlantic. It is understood HMS Vanguard and Le Triomphant were badly damaged in the crash earlier this month. Despite being equipped with sonar, it seems neither vessel spotted the other, the BBC's Caroline Wyatt said."
Nuclear submarines, and especially ballistic missile submarines, don't communicate with anyone at sea unless it's absolutely critical. Communicating gives away your position, and for such submarines, the fact that nobody outside the hull knows exactly where it is is their number one means of survivability. In addition, ballistic missile subs don't have 'allies' - they treat even the surface and submarine forces of their own navy as 'potential hostiles' when at sea in order to maximize their survivability and to continually train to avoid such threats.
Collisions between submarines were fairly common during the Cold War, and were indicative of the amount of time subs spent playing 'hide and seek' with their opponents - because in order to gain intelligence on other submarines, or even to follow them reliably, subs have to be quite close relative to how long it takes them to stop or turn. As a result, however, most collisions were between or involved attack submarines. For two SSBNs to involved in such a bump, either one or the other had to be involved in SSN-like games, or pretty astronomical odds were just surmounted in a random collision. It's a big ocean. It'll be interesting to see precisely where the damage to the two boats is, as it might tell us what aspect they collided at - I have heard it was a slight angle from head-on. Even that doesn't meant they weren't playing silly buggers - if one submarine turned to check its baffles and the other didn't maneuver out of the way, that could result in an angled head-on.
A hero is someone who knows when to run away. I am a hero. -Trent the Uncatchable
Perhaps Sir Humphrey Appleby spoke the truth about the true purpose behind Britain's independent deterrent?...
Real Daleks don't climb stairs - they level the building.
Being ex Royal Navy myself, I know just ho stealthy these SSBNs really are.
We had a two week exercise with the US Navy to hunt for a Vanguard class sub. The sub said its goodbyes, we gave it a couple of hours then we went hunting. Two weeks later we didn't find it. The sub surfaces, only for them to tell us they have been sitting under one of the destroyers hulls all the time.
1 hogshead=238.5 L
238.5 L in 1 hogshead
Plutonium 19.86 g per cm^3
1 liter=1000 cm^3
238500 grams/hoghshead
238500/19.86=12009 grams of plutonium(call it 12 kilos)
1 kilo plutonium, fissioned=20,000 tons tnt
240,000 tons tnt
1 ton tnt=4.184 Gj
1004160 Gj of energy per hogshead of plutonium
40 rods=201 meters
1004160 Gj/201 meters
or a hair under 5,000,000,000 kilonewtons
1 newton being the energy to accelerate 1 kilo to 1 meter per second and the earth being a bit under 6,000,000,000,000,000,000,000,000 kilograms, I don't think we'd notice much.
The british sub, weighing about 14,500,000 kilograms, would get something like 344 meters/second out of it. Or just about the speed of sound at sea level. I imagine that might be a first, for a sub, breaking the sound barrier and taking flight(plummeting glide, really) with those stubby dive planes.
Some one will now rip my math into shreds of sobbing uselessness, probably around the newtons to meters/second part.