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2005-01-12 Home Front: Tech

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Posted by Steve 2005-01-12 9:48:53 AM|| || Front Page|| [2 views since 2007-05-07] Top

#1 But this will generate protests, because active sonar disturbs the fish.

You have got to be shitting me.
But, of course, you're not...

Posted by tu3031 2005-01-12 10:01:42 AM|| 2005-01-12 10:01:42 AM|| Front Page Top

#2 Say what you want, but the sub hit the seamount at ahead flank and they were able to get her back to Guam. This says quite a bit for the design and construction of a 688. It also says a hell of alot about her crew.

Posted by Penguin 2005-01-12 10:24:45 AM|| 2005-01-12 10:24:45 AM|| Front Page Top

#3 hitting anything at 30kts and being able to bring back the boat and all souls but 1, that is more a cause for commendation instead of a career ender (like I first assumed). If this was truly an unknown seamount, and the boat was under orders to mvoe the way it was , then there is no holding the skipper accountable as long as all the regs and procedures were properly followed.

This one goes in my book along with the shuttle disaster as "deaths caused by eco-fascists" (no using the active sonar for the sub, and that cheesy insulation that fell off the booster tank due to "environmentally friendly propellant" changes for the shuttle)

Posted by OldSpook 2005-01-12 10:53:25 AM|| 2005-01-12 10:53:25 AM|| Front Page Top

#4 The decision to reveal the submarine's speed is indeed unprecedented, though very high underwater speeds have been reported for many years. Submarines designed after the late 1950s use the spindle-shaped "Albacore" hull form, which gives higher speed submerged than surfaced. It has consequently been relatively easy to conceal their actual speeds. Contrary to common assumptions, the real advantage of nuclear power is not endurance at sea (which is limited by factors other than fuel) but sustained underwater speed. In water, power requirements increase in proportion to the cube of the speed. 30 knots would require 64 times as much power as 7 1/2 knots, for example.
Some conventional submarines are capable of very high speeds as well, but only for very short bursts, typically an hour or less at full power before the batteries run flat. OTOH, they can run submerged for a week or more at lower speeds. The nuclear submarine, with its enormously higher energy density, can run at high speed for days or even weeks on end.

Posted by Atomic Conspiracy 2005-01-12 10:57:38 AM|| 2005-01-12 10:57:38 AM|| Front Page Top

#5 Sailors versus fishes, employ the sonars, damn it!

Posted by Captain America 2005-01-12 11:16:07 AM|| 2005-01-12 11:16:07 AM|| Front Page Top

#6 I don't think you can blame the eco-nuts for this--submariners don't want to use active sonar unless it's an emergency because it broadcasts their position way beyond its effective range. It's like shining a flashlight in the dark--you can only see the stuff immediately lit up in front of you, but EVERYONE now knows where you are.

I think rather than using active sonar they'll have to restrict depths and speed in areas that are not sufficiently charted and get some dedicated survey ships--like the USNS John McDonnell and USNS Mary Sears mentioned in previous posts--out there to update their navigational charts.

As I understand, active sonar on subs is only employed when under attack. The logic being that the enemy knows where you are already so you activate your sonar to locate him and any other boats out there. Additionally, you'll be twisting and turning at high speed to evade torps which will make your passive sonar useless.

Posted by Dar 2005-01-12 11:27:00 AM|| 2005-01-12 11:27:00 AM|| Front Page Top

#7 Actually, what the protesters have been bitching about is their claim that active sonar negatively affects dolphins and whales.

Regarding underwater speed, the propeller can be turned faster at depth because the higher water pressure prevents cavitation on the back side of the prop.

Posted by Steven Den Beste 2005-01-12 2:13:54 PM|| [http://denbeste.nu/Chizumatic/] 2005-01-12 2:13:54 PM|| Front Page Top

#8 what do you expect when the hydrographic training vessels were used as party boats by the current leadership?

Posted by G5 2005-01-12 2:48:21 PM|| 2005-01-12 2:48:21 PM|| Front Page Top

#9 Explain please, G5.

Posted by Seafarious 2005-01-12 2:53:46 PM|| 2005-01-12 2:53:46 PM|| Front Page Top

#10 I can say no more.

Posted by G5 2005-01-12 2:54:41 PM|| 2005-01-12 2:54:41 PM|| Front Page Top

#11 G5, *whose* training vessels were used as party boats? By *which* "current leadership?" Don't throw something out there you ~~won't~~ can't back up...

Posted by Seafarious 2005-01-12 2:59:45 PM|| 2005-01-12 2:59:45 PM|| Front Page Top

#12 Are they Haliburton Command and Control Vessels now? Has it gone that far? This is what happens when you build the big pontoon boats.

Posted by Shipman 2005-01-12 4:17:50 PM|| 2005-01-12 4:17:50 PM|| Front Page Top

#13 Good to see you visiting here, Mr. Den Beste.

Posted by Brett_the_Quarkian 2005-01-12 4:25:55 PM|| 2005-01-12 4:25:55 PM|| Front Page Top

#14 It was just a snarky comment. Forget about it.

Posted by G5 2005-01-12 4:58:41 PM|| 2005-01-12 4:58:41 PM|| Front Page Top

#15 :) Done that G5.

Posted by Shipman 2005-01-12 6:34:52 PM|| 2005-01-12 6:34:52 PM|| Front Page Top

#16 ... and get some dedicated survey ships--like the USNS John McDonnell and USNS Mary Sears mentioned in previous posts--out there to update their navigational charts.

In the area involved, probably. Maybe a bit larger area too - one doesn't want to draw too much attention to one's survey ships.

As a rule, surveying and re-surveying areas is time consuming and expensive. Not every place needs to be surveyed either. The areas affected by the tsunami that are high-traffic regions will be done. The rest will probably go decades, if not centuries, before a survey is done. I've used charts of regions in the South Pacific and Middle East that had the bulk of the hydrographic data compiled in 19th century (even some late 18th century) with occasional updates since then.

Posted by Pappy 2005-01-12 8:12:32 PM|| 2005-01-12 8:12:32 PM|| Front Page Top

#17 It was just a snarky comment. Forget about it.

It was classified!!! ;)

Posted by Bomb-a-rama 2005-01-12 10:34:33 PM|| 2005-01-12 10:34:33 PM|| Front Page Top

#18 hitting anything at 30kts and being able to bring back the boat and all souls but 1, that is more a cause for commendation instead of a career ender (like I first assumed). If this was truly an unknown seamount, and the boat was under orders to mvoe the way it was , then there is no holding the skipper accountable as long as all the regs and procedures were properly followed.

This one goes in my book along with the shuttle disaster as "deaths caused by eco-fascists" (no using the active sonar for the sub, and that cheesy insulation that fell off the booster tank due to "environmentally friendly propellant" changes for the shuttle)

Posted by OldSpook 2005-01-12 10:53:25 AM|| 2005-01-12 10:53:25 AM|| Front Page Top

#19 Off-topic or abusive comments deleted]

Posted by OldSpook 2005-01-12 10:53:25 AM|| 2005-01-12 10:53:25 AM|| Front Page Top

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