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2005-01-11 Home Front: Tech

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Posted by Steve 2005-01-11 9:05:57 AM|| || Front Page|| [11138 views since 2007-05-07] Top

#1 We need to post speed limits for those mountains - they just move too fast and need to slow down dammit!

Posted by CrazyFool 2005-01-11 9:34:20 AM|| 2005-01-11 9:34:20 AM|| Front Page Top

#2 how could that happen? Don't they have little beepyy things to tell them when a mountain is approaching at a rapid pace?

Posted by 2b 2005-01-11 9:46:20 AM|| 2005-01-11 9:46:20 AM|| Front Page Top

#3 'when its nose cone containing the sonar dome smashed into the rock formation'

sonar works then :)

Posted by MacNails 2005-01-11 9:48:08 AM|| 2005-01-11 9:48:08 AM|| Front Page Top

#4 :-) heh!

Posted by 2b 2005-01-11 9:49:04 AM|| 2005-01-11 9:49:04 AM|| Front Page Top

#5 Well thats certainly far enough way from the Indian Oceam that the earthquake would have had nothing to do with moving anything.

The Mariana's Trench is to the southeast of Guam, and this area I think is pretty deep without counting the trench, so it probably an undersea volcano that never made it to island status (though this is random speculation of course).

Posted by Laurence of the Rats 2005-01-11 9:50:12 AM|| [http://www.punictreachery.com/] 2005-01-11 9:50:12 AM|| Front Page Top

#6 Well, it looks like it's about time to impose mandatory seat belts laws in US subs. And helmet laws. And maximum speed limits. And can we sue the sub maker for not installing sufficiently cushioned bumpers?

Posted by BH 2005-01-11 10:25:23 AM|| 2005-01-11 10:25:23 AM|| Front Page Top

#7 The Braille method of oceanic cartography.

Posted by Seafarious 2005-01-11 10:28:34 AM|| 2005-01-11 10:28:34 AM|| Front Page Top

#8 Air bags. And an immediate recall of the entire fleet for retro fit. This should be under warranty too.

Posted by Mrs. Davis 2005-01-11 10:28:54 AM|| 2005-01-11 10:28:54 AM|| Front Page Top

#9 The Braille method of oceanic cartography.

What happens when you cut Navy Metoc's budget too far.

Posted by anon 2005-01-11 10:41:00 AM|| 2005-01-11 10:41:00 AM|| Front Page Top

#10 When you look at the sailing maps of 500 years ago, you find lots of sea monsters. My theory for that phenomena is that if the captain was fortunate enough to survive his ship sinking, it was better to tell the ship's benefactors that "your vessel was attacked by a sea monster *this big*", rather than say, "I ran it onto some rocks."

Posted by Seafarious 2005-01-11 11:08:29 AM|| 2005-01-11 11:08:29 AM|| Front Page Top

#11 Sure the sub wasnt British made , and was having a crew-exchange with some Canadians ? I think thats where it all went wrong :)

Posted by MacNails 2005-01-11 11:19:54 AM|| 2005-01-11 11:19:54 AM|| Front Page Top

#12 MCN - gives new meaning to "bottoms up"

Posted by 2b 2005-01-11 11:35:15 AM|| 2005-01-11 11:35:15 AM|| Front Page Top

#13 Any possibility that this "mountain" was in fact a huge mound of sediment created by the tsunami? I have heard that the entire region will have to undergo a massive re-mapping by surface ships to determine such changes.

Posted by Anonymoose 2005-01-11 11:37:09 AM|| 2005-01-11 11:37:09 AM|| Front Page Top

#14 That's a hell of a smack, testimony to the skill of the builders.

Brings to mind the tragic accident that A-6 caused by cuting a gondola cable in Italy. No one every wondered why Intruders vertical stabilizer was sliced off. Grumman.

Posted by Shipman 2005-01-11 12:08:50 PM|| 2005-01-11 12:08:50 PM|| Front Page Top

#15 From NYT: A nuclear attack submarine that ran aground Saturday in the South Pacific, killing one sailor and injuring 23 others, appears to have smashed into an undersea mountain that was not on its charts, Navy officials said yesterday. The submarine, the San Francisco, was cruising at high speed - about 30 knots - and was more than 400 feet below the surface when the accident forced it to blow air into its emergency ballast tanks to surface. Some of the tanks were damaged by the impact. One officer said the effort to keep the submarine afloat was initially "very touch and go."
The officials said navigational charts are prepared from both government and commercial soundings of the ocean depths, many dating back centuries. Given the vastness of the oceans, they said, there could still be small areas that were never properly charted or where earthquakes have altered the contours. The officials said it appeared that the San Francisco, which was en route to Australia, had not strayed off course.
"The initial reports are that they were using the proper charts, and they were where they were supposed to be and at the depth they were supposed to be," said a former Navy officer who was briefed on the accident. Investigators will check whether the crew made any errors, officials said.
Similar accidents have happened before, in part because submarines typically do not use their active sonar systems, which emit loud pings, to navigate. Instead, submarines try to operate silently, relying on undersea charts, checks with navigation satellites and passive sonar systems that pick up the noises of other vessels.

Posted by Steve 2005-01-11 12:40:42 PM|| 2005-01-11 12:40:42 PM|| Front Page Top

#16 soooo...does the captain still go down with the ship?

Posted by 2b 2005-01-11 1:08:57 PM|| 2005-01-11 1:08:57 PM|| Front Page Top

#17 2b, I think in this case he goes up with the ship.

Posted by BH 2005-01-11 1:56:28 PM|| 2005-01-11 1:56:28 PM|| Front Page Top

#18 then he goes down.

Posted by Mrs. Davis 2005-01-11 2:05:26 PM|| 2005-01-11 2:05:26 PM|| Front Page Top

#19 Undersea mountains: why do they hate us?

Posted by Mark E. 2005-01-11 2:25:39 PM|| 2005-01-11 2:25:39 PM|| Front Page Top

#20 Like the old joke:

"I know where every one of those undersea mountains are..."
CRASH
"There's one of the damn things now."

At that depth and location, the skipper might have been buring some neutrons. At high speed, sonar is non-functional.

Posted by Chuck Simmins 2005-01-11 3:20:49 PM|| [http://blog.simmins.org] 2005-01-11 3:20:49 PM|| Front Page Top

#21 I'm no geologist, but isn't it entirely possible that underwater volcanic activity may have caused this mountain to grow over time--making navigational charts for that area obsolete? It'd take a lot of activity to grow rapidly enough to be a navigational threat like this, but it is theoretically possible and wouldn't be as spectacular or noticable as a Mt. St. Helens if it were all underwater.

Additionally, sonar isn't much good for finding underwater obstacles unless it's actively pinging, from what I understand. And active sonar is rarely used because it advertises your presence over a much greater distance than its effective range--submarines generally use passive sonar, i.e. just plain listening, to detect screw noises. A big rock doesn't generate any noise and is undetectable to passive sonar.

I agree with Chuck that at that speed (flank speed?) passive sonar is useless because the water rapidly rushing past the boat masks other noises, but I don't think it'd have made any difference since mountains are basically silent.

All this is the opinion of someone who gets all his sub-knowledge from Clancy books, however. I would welcome some enlightenment from anyone in the know!

Posted by Dar 2005-01-11 3:39:32 PM|| 2005-01-11 3:39:32 PM|| Front Page Top

#22 Something sounds fishy here. If a sub was going that fast ran head on into a mountain there should have been a h*** of alot of damage. Unless it barely scraped an outcropping.

Posted by Stephen 2005-01-11 10:00:18 PM|| 2005-01-11 10:00:18 PM|| Front Page Top

00:25 screw the brick
00:00 RWV
23:57 anonymous2u
23:34 Zenster
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22:50 Angash Elminelet3775
22:43 anymouse
22:39 RWV
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21:56 Anonymous4724
21:53 Sock Puppet of Doom
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