Sub Collision- How does this happen?

[Gator95]

The sonar used on nuclear subs is usually a towed array way behind the sub and hundreds of meters long. Its like a 1-2" diameter rope with thousands of microphones and amplifiers. Then they also have planar w-D arrays on the sides of the sub. By combining the signals in array processors, the signal can be amplified and beam steered - its possible to get very small aperature and high gain same as can be done with antennas except the scale is much different.

Guess I always figured that the 'hole in the water' meant that an attack sub couldn't hear a boomer running quiet from about a half-mile or so. Would have figured that once you got to 500 yards that they'd be detectable... guess not.

[gerti]

Didn't the British Navy install windows on their boats? Probably crashed or got infected by that currently spreading virus...

[TheChief]

Don't count on a lot of details from us submariner-types. We tend to be (or at least should be) a little tight-lipped. :zip:

The most I'd wager to guess in public is that there was probably some sort of non-interference message that either wasn't sent, wasn't received, or wasn't properly charted by one or both sides. Human error will be cited and regardless of where the fault lies neither C.O. is likely to command again.


An aside, re the "nuclear torpedo": I will venture to guess that while there may be a psycho country or two out there that has them, any sane navy would not use torpedoes with nuclear warheads on their fast attack (the so-called "hunter-killer") subs, several other types of tactical and strategic missiles notwithstanding.

The U.S. played around with the idea a while back but as I recall it was one of the few tactical weapons considered to have a kill factor of 2.0: given the blast radius of even a small warhead it would be highly unlikely the firing sub could get far enough away to avoid being destroyed along with the target.

Aside from that, really, a few hundred pounds of HE popped off in just the right place is plenty enough to take down pretty much anything that needs taking down, without all that nasty fallout.

[LCHIEN]

that does seem to be the case, that nuclear torpedos are no longer deployed. One problem is that these were wire-guided torpedoes so the firing sub had to hang around until they hit.

Still the current US torpedoes are reputed to have a range of about 24 to 30 miles depending on whether they are in high speed mode or slower mode (55 kt or 40 kt.)
Given that the firing sub can now go 30-40 kts in the opposite direction during the 30-40 minutes the torpedo is reaching its destination, the firing sub can travel another 15-30 miles away before it detonates meaning it can be 39 to 60 miles away if it didn't want to stay for the after-game party.

[ragswl4]

I would not be surprised that someone was asleep at the switch on one or both of the subs. Anyone remember our sub that surfaced under a tourist boat in Hawaii? Now that should never, never have happened.

Also possible that a sonar system was inoperative at the time. I heard that the French sub was damaged near the bow so maybe she was the "hitter".

Years ago a sub surfaced directly in front of an aircraft carrier at close range, so anything is possible. Hard not to hear an aircraft carrier when you are in a sub. Duh! Them submarine guys are good through, right up there with aviators when it comes to their professionalism. At least they were back in the day.

Nuke torpedoes? I can neither confirm no deny.

ragswl4
Retired Senior Chief Sonar Techncian (Surface)

[Copper]

from http://news.yahoo.com/s/ap/20090216/..._sub_collision Stephane Lhomme, a spokesman for the French anti-nuclear group Sortir du Nucleaire, said his organization is checking the French coastline for evidence of any leak of radioactive material.

I find this quite humorous since they are looking almost two weeks after the fact for something that likely happened hundreds of miles offshore and underwater. Did they actually think they would find anything even if there were some kind of Chernobyl-type event?

[ragswl4]

I find this quite humorous since they are looking almost two weeks after the fact for something that likely happened hundreds of miles offshore and underwater. Did they actually think they would find anything even if there were some kind of Chernobyl-type event?

That's really funny, given that France produces more than half of its electricity from nuclear power. Seems like that organization would better spend its nickels checking those nuke plants. As far as the subs leaking something it would be easier to check the sailors for sudden onset of hair loss than poking around in the ocean.

[radhak]

Imagine, such a long discussion and I had been ignoring it. I somehow thought y'all were talking about eating one too many at Quiznos...!

[LCHIEN]

Il es le coque. Je suis le renard.

It is the hull. I am the fox. (Babelfish translation)
???

[L. D. Jeffries]

The answer is pretty easy! Salt water stings the eyes; sooo' they had their eyes closed! LOL

[Hellrazor]

I find this quite humorous since they are looking almost two weeks after the fact for something that likely happened hundreds of miles offshore and underwater. Did they actually think they would find anything even if there were some kind of Chernobyl-type event?

They were looking for the white flag holder that broke off the French Sub...

I still can believe they let the French have a nuclear sub. I am waiting for the news story "French Sub crew surrenders to 2 natives in a dugout canoe".

[Bruce Cohen]

The REAL reason has to do with France's equal opportunity movement.







It was a woman driving the sub.

Bruce

[Crash2510]

french navy sub

nuff said

for something funny go to google homepage

type in "french military victories"

hit im felling lucky go to did you mean first response funny

[gary]

Maybe the French were all taking their monthly bath!

[milanuk]

Another thing to consider... passive sonar doesn't have the best directional capability unless you do a few course changes to triangulate. Yes, you can hear lots of things with a towed array. You can even make pretty good guesses as to how fast they are going, how far away they are, relative bearing, that sort of thing. But compared to active sonar... things are a lot more... well, 'fuzzy'. Works pretty well most of the time - barring things like wood-hulled small boats, snafu's in the inertial guidance (not like you get the best GPS reception down there), or when the target turns before you do

Or least thats what I recall from my time on fire-control tracking party up front w/ the coners