What it looks like to hit an underwater mountain.

[RWB]

Here's what it would look like if a sub hit an uncharted undersea mountain....
http://www.fas.org/main/content.jsp?formAction=297&contentId=396

Wow... them subs can take some damage! And after I saw a discovery channel show on the theory of imploding subs, I am even more surprised!

[TheSmJ]

Dont they have sonar that can "see" the underwater terran before hitting it?

[NiGHTS]

Yes, they do.

[TheSmJ]

So WTF then?

[pseudonym]

It only works when its turned on. If they are running with it off then they aren't putting out any sound waves to bounce off the objects. I think they determine their position by velocity and time so if they are off on the map or a calculation could be wrong...

Hell, they can't get GPS down there can they?

[KingFish]

Ouch, that look like it hurt.

[deicist]

I think they determine their position by velocity and time so if they are off on the map or a calculation could be wrong...


Yup, that's how they do it. In this case the undersea mountain they ran into was an uncharted one. Ie: it wasn't on the map.

[Xander]

It said that they were doing a high speed run. When you do that you can't hear anything because of all the water going by the sub. If they had slowed down they would have "seen" the mountain.

That is not pretty. In the first picture if you look underneath where the guy is standing you can see a part of the hull was forced up by the impact. That had to have been a hard hit. Good thing we build'em so tough.

[csimon]

:banghead: maybe they swirved to avoid flipper? ;D

[Armo]

FLIPPER! where are the drug runners?!

[Preacher]

Submarines don't have an active sonar that can "see" underwater obstructions such as pinnacles and sea mounts. They have velocimeters and fathometers which tell them their speed and depth, but they point down and have no roll in obstacle avoidance. They do have a tactical active sonar that can find exact bearing and range to a contact, but it is rarely used. It gives away your positon at a much longer range than that which you can find the same contact. They determine their position by regular GPS fixes at shallow depths and constant use of amazingly accurate inertials. Then they plot their location on bottom topography charts. It seems that the obstruction they hit was uncharted. They routinely do high speed runs for training, and at high speed, they do go deaf. However, even at low speeds, they wouldn't have been able to hear or see this mount. Luckily, we do build them tough from lessons learned from the Thresher and the Scorpion losses in the 1960s.

[Komete]

Hw fast is hi speed for a big sub like that?

[danball1976]

Probably 30-40 Knots is hi-speed.

[RWB]

Hw fast is hi speed for a big sub like that?


Usually classified.

[danball1976]

Just like how the B-2's top speed is classified. It can be only assumed based on design what a sub or aircraft's speed is.

[RWB]

Dunno if this helps, but the USS Nautilus set a speed record of 23Knots underwater, but that was back in 1955 I think. Every sub to leave construction is an upgraded version of the last, so each one has new capabilities that the former may not.

These things are true beasts, but depend on humans more than one may like. Humans of course must make sure EVERY weld is a perfect one. Or else.

The theory behind a implosion is nothing like what you see in movies, actually what they think happens is that the ship stays intact. But the pressure of the water at such deep depths are so great that a small hole almost instantly floods the entire sub. Of course to do that the water rushes in so quickly that you die instantly. It may break up as it hits the ocean floor.

[Preacher]

For those interested, the unclassified fact file on US Navy's Los Angeles Class Submarines..

http://www.chinfo.navy.mil/navpalib/factfile/ships/ship-ssn.html

Virtual Tour

http://www.pbs.org/wgbh/nova/subsecrets/inside.html

[Crazy Joe]

Ya, and Cincinnati is getting a decomissioned LA Class (USS Narwhal) Sub in 2007... It's going to be pretty awesome to be able to walk through it...

[RADA]

Just watched a Discovery Channel program on the USS Virginia. This is the latest fast attack boat in the US Navy. They stated her top speed is in excess of 25 knots. She also has the capability to deploy a 9 - man Seal team while still submerged.

[Camman]

I just watched that same show too, interesting stuff!

[GHoosdum]

Ya, and Cincinnati is getting a decomissioned LA Class (USS Narwhal) Sub in 2007... It's going to be pretty awesome to be able to walk through it...

The Narwhal is not a Los Angeles class sub. AFAIK, all of the Los Angeles class subs were named after US cities. The Narwhal is more related to the Sturgeon class and was built before the Los Angeles class, but was really the only ship of its class.

[Preacher]

Ghoosdum, you are wise in the ways of the undersea force. There are 4 active classes of tactical submarine in the U.S. Navy (we do have some research subs as well). They are the Los Angeles Class of attack submarines (SSN or "fast attack"), the Ohio Class of Ballistic Missile Submarines (SSBN or "boomer"), the Seawolf Class of attack submarines, and the 4 Ohios that were modified to carry Tomahawk cruise missiles (~150!!) as SSGNs. They are building a new SSN class called the Virginia that is more advanced than the LAs, but cheaper than the Seawolves.

For those interested...

SSNs
http://www.chinfo.navy.mil/navpalib/factfile/ships/ship-ssn.html
SSBNs
http://www.chinfo.navy.mil/navpalib/factfile/ships/ship-ssbn.html
SSGNs
http://www.chinfo.navy.mil/navpalib/factfile/ships/ship-ssgn.html

[Crazy Joe]

Well that's what I get for mixing my information... When they were first talking about getting a Sub for Newport they were wanting a LA class (the USS Cincinnati would have been appropriate)... Then I went and searched for the name of the sub they did get and didn't look to see what class it was...