Did whispering on submarines really make a difference? [Archive]

Boris B

05-01-2000, 11:42 PM

Yeah, I was gonna say what Ellis said. Having everybody whisper reminds the crew to be quiet in more important ways, like not dropping wrenches, or drumming nervously on the bulkhead with spoons (I've never heard of that happening, but it would be bad if it did). I suppose it is a good way to remind new recruits how sound is everything (or nearly everything) in submarine warfare.

I heard of a story of a World War I German merchant submarine (!) which was being hunted in shallow waters around Britain. The Germans were on their way to the neutral U.S., and they were sitting on the bottom waiting for the RN to give up, so they sang, "We've rings on our fingers and bells on our toes!" I don't know if there are German lyrics to that one, or if they sang in English. That's not particularly relevant since WWI hydrophones were fairly primitive; I don't even know if the British had them at that point (they got them in 1916?, and this story takes place in 1914 or -15?) I like the story anyway. Upshot: the Germans made it across the Atlantic, but submarines were never a significant part of the Kaiser's merchant marine.

Profane

05-02-2000, 12:55 AM

I asked Mr Lunasea (who is a submariner) and he says that it does make a difference. The listening capability of subs is amazing, and we all know how well sound travels through H20. When they call for quiet it pretty much means all movement & speaking ceases, as far as I know.

bibliophage

05-02-2000, 02:08 AM

Boris said
They were sitting on the bottom waiting for the RN to give up

A month ago I would have wondered whether submarines ever do rest on the bottom. Then I read a book about German U-boats in WWII in which it is mentioned several times that they rested on the bottom, especially when trying to hide from surface ships. I'd heard the myth that a sub resting on the sandy bottom would get stuck because of the pressure. I didn't quite believe it, but I wasn't sure. A little research turned up this site (http://www.cebaf.gov/kids/archive/submarine.html) that explodes the myth.

Whack-a-Mole

05-02-2000, 08:57 AM

Was passive sonar used in WWII? It seems that back then their listening techniques weren't very refined. There were no helicopters in WWII to carry dipping microphones and I don't recall naval ships having towed arrays back then either. Remember, your own ship is too loud to allow listening for anything useful if the hydrophone is glued to the keel (hence modern naval ships tow the hydrophone behind them). Also, I don't think there was any such thing as sub vs. sub warfare in WWII. As a result subs themselves didn't carry hydrophones of their own. They always came near the surface and checked things out with their periscope. Even if they could detect another sub they couldn't hit it with anything other than the luckiest shot in the world (torpedos weren't guided back then).

If this is so then talking on a sub in WWII would make little difference as no one is listening. What the destroyer on the surface is listening for is the return ping of their active sonar. The trick of sitting on (or near) the bottom was so the sub became part of the background and the destroyer couldn't distinguish the sub from a rock or the sandy bottom.

Of course, today things are much different. As several people have already mentioned the hydrophones these days are VERY good. Talking on a submarine today could quite possibly get you into trouble. This must be the case if for no other reason than the navy goes to EXTREME lengths to make sure there are no noisy anything in a sub (all tools rubber coated, etc.). I doubt they'd go to all the trouble if there wasn't a real concern of being heard.

Fiver

05-02-2000, 09:37 AM

Did whispering vs. talking really make a difference as to whether or not they were detected by enemy subs and/or enemy surface ships?

I can't say anything about WWII-era submarines, sonar, or hydrophones, but by the time I was in the Navy from 1989-1993 (admittedly on a surface ship) I knew that it does make a big difference. Submariners (or "bubbleheads" as they like to call themselves) even wear sneakers onboard, as opposed to the noisy hard leather workboots we wore on surface ships. Submarines do everything possible to minimize all kinds of noise.

And, as a tangentially-related fun fact, US Navy minesweepers obsessively minimize their magnetic signature, presumably to protect them from mines. Check it out:

A minesweeper's hull is made of wood coated with fiberglass.

Its engine is made of non-ferrous metal.

Minesweeper crews go so far as to wear wooden belt buckles, and any bits of metal they may bring on board, like wedding bands or car keys, must be entered into a log upon boarding.

All this, despite the fact that most mines don't work magnetically these days.

Boris B

05-02-2000, 11:38 AM

http://www.ob-ultrasound.net/hydrophone.html
http://www.uboat.net/allies/technical/asdic.htm
http://www.ukans.edu/~kansite/wwi-0699/msg00134.html

Those URLs should back up my contention that hydrophones have been used since 1916, at least aboard anti-submarine surface vessels. When they were first fitted to submarines, I don't know.

The first one contains some weird claims, like hydrophones being used to detect icebergs. I mean, are icebergs really that noisy? So proceed with caution.

The third one is just a BBS message, but the writer seems like he know his stuff.

Narile

05-02-2000, 11:58 AM

Yes Boris, icebergs are that noisy. Ice has a lot of shear lines that like to shift as the 'berg melts, and those shear lines creak quite loudly.

Ukulele Ike

05-02-2000, 12:32 PM

reminds the crew to be quiet in more important ways, like not dropping wrenches, or drumming nervously on the bulkhead with spoons

Sorry.

This just KILLED me.

I suddenly had a visual flash of everyone on the submarine being really quiet because there's a British ship going by above, then one guy drops a wrench, and everyone jumps and goes SHHHHHHHHH!!! And then someone starts drumming nervously on the bulkhead with spoons, and everyone jumps and goes SHHHHHHHHHH!!! And then one sailor starts nervously to play the Sousaphone...

A real Monty Python moment.

Doctordec

05-02-2000, 01:23 PM

Head down to the video shop and rent...

Run Silent, Run Deep
Destination, Tokyo
The Enemy Below

Everything you always wanted to know about WWII submarining.

"What is it sir ? I can't make it out."

Boris B

05-02-2000, 01:45 PM

Narile Thanks for the info. I remember hearing something on NPR where somebody tape recorded some pack ice. It was very creaky. So I guess it makes sense that icebergs are noisy; I just always assumed they were detected with active stuff.

Ike Let me guess, then the commanding officer comes down from the tower to figure out what all the fuss is about, gets angry, and draws his pistol, threatening to shoot the next guy who makes noise. The whole crew then looks really worried and shakes their head, fingers to lips.

Five The magnetic signature thing reminds me of speculation that the Soviet Alfa class submarines, with their titanium hulls, would be invisible to NATO magnetic anomoly detectors. I don't know if there was enough ferrous metal inside them to trigger the MADs, and I don't know if the titanium hulls were designed for that purpose, or for deep-diving capabilities. The Alfas were said to be able to make 40 knots.

Fiver

05-02-2000, 02:34 PM

Head down to the video shop and rent...

Run Silent, Run Deep
Destination, Tokyo
The Enemy Below

Everything you always wanted to know about WWII submarining.

How can you compile such a list and leave out Das Boot?!

Whack-a-Mole

05-02-2000, 02:37 PM

Boris_B
Those URLs should back up my contention that hydrophones have been used since 1916, at least aboard anti-submarine surface vessels.

Interesting links. While they do show that passive sonar was used it sounded nearly worthless and they relied much more on active sonar (pinging). The passive sonar, according to your links, needed fairly loud noises (machinery) and has to be relatively close to be of much use. I still doubt that talking would cause you to be caught in a WWII submarine.

I will say, however, that it's probably human nature to be quiet when being hunted. Some primal leftover that tells us if a predator is near making a noise is probably a bad idea. Chances are good that whether or not talking was a bad idea I'd still probably keep my trap shut if a destroyer was lurking above.

Alphagene

05-02-2000, 03:30 PM

I suddenly had a visual flash of everyone on the submarine being really quiet because there's a British ship going by above, then one guy drops a wrench, and everyone jumps and goes SHHHHHHHHH!!! And then someone starts drumming nervously on the bulkhead with spoons, and everyone jumps and goes SHHHHHHHHHH!!! And then one sailor starts nervously to play the Sousaphone...
And for the punch line, the camera pans up to reveal the highly unsuccessful British anti-sub ship, the H.M.S. Helen Keller:

"Any sign of enemy submarines?"

"What?"
"Huh?"
"Come again?"
"Did you just say sumfin'?"

Olentzero

05-02-2000, 03:36 PM

From Boris B:
The first one contains some weird claims, like hydrophones being used to detect icebergs. I mean, are icebergs really that noisy? So proceed with caution.

Actually, I've heard stories that scientists were actually able to translate the creaks and groans of a few North Atlantic icebergs into English:

A: "Hey, remember that big one Bob got in 1912?"
B: "*snort* haw haw haw..."
A: "Ssssh! Here comes another one."

Spiny Norman

05-02-2000, 03:41 PM

Thanks, Five, for mentioning "Das Boot" - I wanted to add it to the list, but didn't know if the title had been translated.

Oh, and On-On right back at you (Last Boy Scout, H7, Germany).

sailor

05-02-2000, 03:48 PM

Not too long ago I saw documentary done on a US sub on patrol. A few things I remember are:

They would go into *silent* mode and it *was* silent! Everyone not on active duty had to lie silently in his bunk. Everyone else was extremely silent!

They were listening to everything going on around them and sometimes it was whales and other natural stuff. The sounds were signature analyzed by computer to establish, origin, direction, distance etc. In spaite of everything it wa not always 100% clear.

There was a case of espionage a few years back when the russians got some info about how the USA makes their props so they are very silent, much more silent than Russian props are. This is very important as this prop noise allows sub detection.

In certain strategic places, like the straight of Gibraltar there are plenty of listening devices to track any subs passing.

Fiver

05-02-2000, 04:10 PM

Oh, and On-On right back at you (Last Boy Scout, H7, Germany).

Hey, all right! R U?

Where in Germany are you? My friend Little Sister (a man) just got back from Frankfurt.

Fiver

05-02-2000, 04:18 PM

Spiny Norman wrote:

Thanks, Five, for mentioning "Das Boot" - I wanted to add it to the list, but didn't know if the title had been translated.

Not only was Das Boot brought to America, it came over in two versions. One was subtitled, and one was dubbed.

The dubbed version received much more care than is usual for foreign films. The film's original director produced the new vocal track, and he brought the whole original cast into the studio to dub their own lines into English. The result is quite satisfying.

Revtim

05-02-2000, 05:29 PM

There was also a "Director's Cut" version of Das Boot, which actually is the only version I saw. I'm pretty sure it was dubbed.

brad_d

05-02-2000, 08:17 PM

brad_d

05-02-2000, 08:31 PM

Was passive sonar used in WWII? It seems that back then their listening techniques weren't very refined.

It was. And it's also true that, compared to modern standards, it was pretty stinkin' primitive. :)

I believe that US subs had both active and passive, but very rarely used the active since it's like walking through the woods at night with a flashlight - somebody will see you coming long before your light illuminates them.

There were passive sonar heads outside the hull, and they rotated to give bearing information on sounds. There wasn't any computer processing, so the sonar guy's ears were awfully crucial filters. They could pick out individual ships and give approximate bearings and estimates of distances. They could also hear depth charges splashing as they were dropped into the water overhead.

I THINK that destroyers relied more on active sonar when pursuing subs. Subs were pretty quiet, and the destroyers themselves were pretty loud (somebody correctly pointed out that they didn't have towed arrays). I've been led to understand that destroyers pretty much had to go dead in the water to get use out of their passive sonar, and they occasionally did just that.

I'm no bubblehead, so any of the above information might be wrong. I welcome any corrections or additions.

A couple of really good books on WWII submarining are by Harry Homewood. They're called "Final Harbor" and "Silent Sea" (SS is a sequel to FH). Homewood served on subs in WWII, and goes into a fair amount of detail in his novels. I believe they are out of print, but one can probably still find them through amazon.com and similar sources.

Kyberneticist

05-02-2000, 08:41 PM

I just watched the recent Das Boot rip-off, and they did indeed have the guy at the headphones reporting how many depthcharges were dropped, presumably by counting splashes.

I wonder why the charges were set to a particular depth, rather then, say, triggered by metal like mines were. After all, it's not like you could build much of a sub out of wood...

brad_d

05-02-2000, 11:59 PM

I wonder why the charges were set to a particular depth, rather then, say, triggered by metal like mines were. After all, it's not like you could build much of a sub out of wood...

The US did try magnetic triggering of depth charges during WWII. They were apparently pretty successful at obtaining kills on the rare occasions when they didn't totally malfunction. :) The reliability problem sounds like the only reason they didn't get more widespread use.

For reference, see http://www.microworks.net/pacific/armament/depth_charges.htm.

The US subs were also plagued by magnetic exploders in their torpedoes at the start of the Pacific campaign. The idea was that the fish would travel below the keel of the target ship and detonate there, triggering off the magnetic field of the metal target. Since most of the explosive force gets directed upwards, this is far more effective than an explosion against the side of a ship's hull.

But the things just didn't work. http://www.microworks.net/pacific/armament/mk6_exploder.htm.

Billdo

05-03-2000, 12:31 AM

A couple of really good books on WWII submarining are by Harry Homewood. They're called "Final Harbor" and "Silent Sea" (SS is a sequel to FH). Homewood served on subs in WWII, and goes into a fair amount of detail in his novels. I believe they are out of print, but one can probably still find them through amazon.com and similar sources.

The best submarine book from WWII, bar none is Run Silent, Run Deep by Capt. Edward L. Beach, a WWII submarine officer and respected naval historian, the book that practically invented the genre. Beach also wrote two sequels, Dust on the Sea and Cold is the Sea, as well as a great deal of other naval non-fiction.

If you want non-fiction WWII submarine stories, you should check out the two books by Rear Admiral Richard H. O'Kane, one of our most distinguished submarine skippers and winner of the Medal of Honor for his exploits. His first is Wahoo : The Patrols of America's Most Famous World War II Submarine, which details his service on the U.S.S. Wahoo including his time as executive officer under the legendary Dudley "Mush" Morton. The second is Clear the Bridge! : The War Patrols of the U.S.S. Tang, the story of the submarine he commanded during the war.

Spiny Norman

05-03-2000, 12:34 AM

Three and a half hours ? It's intense, but even so. The original original German version was a TV series, so they presumably had plenty of material.

Dubbing is, IMHO, most often barbaric, but I guess sometimes necessary. When I watched the series, one of the things that really got me was the "everyday" German spoken by the characters. I suppose I'll have to find the DVD.

[H3 thread hijack]
Five, I run with Hamburg - I haven't met Little Sister (not that I recall), but then again I've never been to Frankfurt to hash, and I didn't make it to the last Eurohash. Used to visit West Rhine H3 (Munich) all the time. You're running with ?
[/H3 thread hijack]

Jinx

05-03-2000, 07:23 AM

I'm non-military, so I have to defer to the squids on the board, but from what I understand, submarines (the modern ones, at least) run quietly enough that they can hear transient noise coming from inside another one at close range, including voices coming from inside.

Water, don't forget, is an excellent conductor of sound energy.

If they can dampen out the noise of the propulsion and its supporting systems, then it's very hard to believe a whisper wouldn't also be dampened out somehow. What if someone sneezed? Maybe someone can elaborate further...

Jinx

05-03-2000, 07:34 AM

I should clarify. My reply refers to modern times. And, I know you're gonna say they cut the propulsion when they need to be silent. Still, there are some supporting systems you cannot afford to cut off. I can only WAG that a constant droning sound, the frequency of which is probably easily determined, may be easier to cancel out somehow as opposed to a sneeze with a sound signature perhaps all over the audio spectrum!

So, I ask in light of today's technology: Would one stray noise, a sneeze for example, blow 'em away, literally?

Ukulele Ike

05-03-2000, 08:30 AM

Wahoo : The Patrols of America's Most Famous World War II Submarine

The most famous American WWII submarine was called the Wahoo?

I'm having another Monty Python moment.

Billdo

05-03-2000, 09:42 AM

The most famous American WWII submarine was called the Wahoo?

Sure thing. Some links:

http://www.csp.navy.mil/ww2boats/wahoo.htm

http://www.twics.com/~mackinno/wahoo-home.html

http://www.subnet.com/fleet/ss238.htm

http://www.warfish.com/warfish/index.html

For a thread on the definition of the name of the fish wahoo:

http://boards.straightdope.com/sdmb/showthread.php?threadid=2591

warinner

05-03-2000, 10:01 AM

Jeff_42 wrote:

Also, I don't think there was any such thing as sub vs. sub warfare in WWII. As a result subs themselves didn't carry hydrophones of their own. They always came near the surface and checked things out with their periscope. Even if they could detect another sub they couldn't hit it with anything other than the luckiest shot in the world (torpedos weren't guided back then).

The British used hunter-killer submarines quite a bit in WWII. British subs sank at least seven German and Italian submarines if I recall correctly.

Also, WWII-era subs spent almost all of their time on the surface because of their slow submerged speed, limited endurance on batteries and generally unpleasant effects of a lack of ventilation. Sure, schnorkels were extensively used later in the war, about they were loathed by German submariners.

Andrew Warinner

Profane

05-03-2000, 10:05 AM

So, I ask in light of today's technology: Would one stray noise, a sneeze for example, blow 'em away, literally?

Mr Lunasea says that the biggest culprit is the metal toilet seats banging down on the metal toilets. The noises that will really give them away are things that are connected to the hull, dropping a wrench, using the loudspeaker, running etc.

Fiver

05-03-2000, 11:36 AM

[H3 thread hijack]
Five, I run with Hamburg - I haven't met Little Sister (not that I recall), but then again I've never been to Frankfurt to hash, and I didn't make it to the last Eurohash. Used to visit West Rhine H3 (Munich) all the time. You're running with ?
[/H3 thread hijack]

I'm in Atlanta, which is a veritable Hash Wonderland. There are several local hashes; as listed here:

http://www.atlantahash.com/otherhashes.htm

I've never hashed outside Atlanta, but I have been to Muenchen, so I bet there's great hashing there at least.

Rodd Hill

05-03-2000, 12:06 PM

"Psssst...hey Buddy...the First Mate is a schnook...pass it on!"

Narile

05-03-2000, 06:35 PM

I thought that the Tang was the most decorated ship in WWII, with the most kills. (Its last kill, alas, was itself.)

As for the MAD detection of the Alfa's, I'll ask my brother when I talk to him next, he is an S-3B Viking pilot, and a graduate of ASW school. (Fun thing there, both his roommates at VMI are now submariners. :) )

ubermensch

05-03-2000, 09:56 PM

Boris B

05-03-2000, 11:58 PM

for brad_d and Jeff_42
According to Anti-Submarine Warfare p. 10 (sorry I don't have a complete cite; I photocopied the page from the library and didn't record the author or publisher) ... After the formation of the Anti-Submarine Division of the Admiralty in December 1916, hydrophones went to the sea in increasing numbers. The Nash Fish, a towed hydrophone that could even indicate the direction of a noise source, was first fitted in July 1917.
I don't the scale on which these were issued, or to what kinds of vessels. I don't think the UK had a dedicated class of small sub-hunters in WWI, so I imagine they fitted them to ordinary fleet destroyers.

The US, on the other hand, had its class of 110-foot subchasers. According to Jane's Fighting Ships of World War I Boats fitted out [with hydrophone gear] have either (a) K-tube fish hydrophones of 30 miles acoustic radius, or (b) SC and MB hydrophone tubes built into (and insulated from) hull of 3 miles acoustic radius.
So I suppose not all 331 USN subchasers were fitted with hydrophones in the first place. Anyway, I am surprised at both the claimed "acoustic radius" (radius for detecting what? a submarine? what type? at what speed? what depth?), which seems very optimistic, and the fact that they were fitted to 85-ton wooden motorboats. Unfortunately, Janes' didn't discuss ASW sensors of American fleet destroyers.

Anyway, I hope this clears up some of our questions about anti-sub capabilities in the early part of the Century. I don't have any stats on the acoustic radius for a K-tube fish to detect a sneeze though. *sigh*

aseymayo

05-04-2000, 12:30 AM

Thank you, Uke.

And I'm very disappointed to find out what "Hash Wonderland" means these days.

Fiver

05-04-2000, 07:47 AM

aseymayo

Thank you, Uke.

And I'm very disappointed to find out what "Hash Wonderland" means these days.

Sorry, chick. Life is disappointment.

aseymayo

05-04-2000, 03:27 PM

Oh, dear, is it? I thought it was a pigeon flying in through an open window, or perhaps something to do with underwear, and now you tell me it isn't. That is disappointing...hey! you're right!

Who wants ice cream?

Billdo

05-04-2000, 07:09 PM

I thought that the Tang was the most decorated ship in WWII, with the most kills. (Its last kill, alas, was itself.)

Well, Admiral Richard O'Kane, who served as Executive Officer of the Wahoo and commanded the Tang (and was one of the few survivors of the circular torpedo run that destroyed it) subtitled his book describing his service on the Wahoo, "The Patrols of America's Most Famous World War II Submarine."

According to the U.S. Navy Website (http://www.csp.navy.mil/ww2boats.htm):

"WAHOO was one of the Submarine Force’s most valuable units during her six patrols, and her feats have become submarine legend. She sank 27 ships, totaling 119,100 tons, and damaged two more, making 24,900 tons, in the six patrols completed before her loss," and she was awarded one presidential unit citation.

"In her five patrols, TANG is credited with sinking 31 ships, totaling 227,800 tons and damaging two for 4,100 tons. This record is unexcelled among American submarines." She was awarded two presidential unit citations and her captain, O'Kane, received the Medal of Honor and two Navy Crosses for his service.

Both ships were tremendously successful and justly famous and decorated. I strongly recommend O'Kane's books which vividly describe the exploits of these ships.

egkelly

05-05-2000, 07:04 AM

For all you WWII sub buffs-in the movie "DAS BOOT", there is a scene where they take a deep dive (the depth gauge reads in the RED zone. At this great depth, they hull starts making creaking noises as it contracts under the pressure-then you hear sounds like rifle shots-the bolts securing the hull plates to the frame start shearing off-is this true? I've never heard of any WWII submariner reporting such a thing-seems to me that this the last thing you would hear before the sea rushed in!

hightechburrito

05-06-2000, 01:15 AM

i'm shocked that no one mentioned that classic kelsey grammer film where he plays captain to a bunch of rag-tag submariners who are in a wargame. the movie was so classic that i forgot the name, and don't care to go to IMDB to look it up. anyway, they go silent for a bit..no one talks..something happens (a guy farts, i think) so they get busted, right? NO! they start singing "louie louie" to give the impression that they are a pleasure boat and having a party (i think there was a fishing trawler nearby) and they avoid detectance! classic!

The movie is either called Up Periscope or Down Periscope. In one scene they rest on the bottom and one guy makes whale noises so the other sub goes away. And in another scene, they put a light on the top of the periscope and surface, so they look like a sailboat, and then they sing Louie, Louie.

Amusing, yes. But a classic?

Narile

05-09-2000, 02:29 AM

Well, I talked with my brother the S-3B pilot last night and he gave me the following regarding MAD and the Soviet Alfa.

The titanium hub helps, but that by itself isn't enough.
Modern sub hulls are periodically degaussed, and this helps more than anything else in avoiding MAD detection. (I'm not sure how often they are degaussed, he didn't say)
The biggest advantage to the Alfa's hull is that it can dive really friggin deep.

Boris B

05-09-2000, 10:33 AM

casdave

05-09-2000, 12:25 PM

De-gaussing is done on most modern warships as well as subs.

The system comprises a few turns of very heavy duty electrical cable laid inside the vessel but in a loop.
Replacing this cable when idiot dockyard welders cut through them is not a job to be envied as it is physically heavy stuff and it is generally not very accessible.I know all about it.

To get rid of the magnetic signature of the vessel which increases over time as electrical equipment is used a direct current is passed through the coils .It is ramped up to full current, since it is current that is responsible for magnetic fields and not voltage, and then ramped down again.

This is done periodically and is often part of the operational training trials where the vessel is taken across an area where there are instruments in the sea bed designed to detect the magnetic signature.

Actually de-gaussing is done right before your very eyes, your monitor has de-guassing coils in it. They are designed to prevent the shadowmask just behind the screen front being magnetised as this would affect the colours displayed.

craxonius

06-14-2000, 03:48 PM

A phenomenal (fictional) book on subamarine warfare is Neal Stephenson's latest novel, "Cryptonomicon". I was stunned when "U-571" was released a few months after the book hit the shelves - it's basically the same story! How the allies got the "enigma" code from the Germans. It's a long book, and the author sometimes bogs down in esoteric cryptology mathbabble, but there are plenty of nail-biting combat scenes and underwater dramas, and you not only get to view WWII in the European, but also in the Pacific theatre. It's a real feel-good WWII action drama, sort of a cross between all three of the hottest such screenplays lately: The Thin Red Line, Saving Private Ryan, U-571.

Jophiel

06-14-2000, 05:10 PM

Hijack in progress...

Actually de-gaussing is done right before your very eyes, your monitor has de-guassing coils in it. They are designed to prevent the shadowmask just behind the screen front being magnetised as this would affect the colours displayed.
Huh.. and here I thought the DEG button was just there to make the screen go all wavey and the colors mess up for a few seconds. Scared the hell out of me first time I pressed it.

Gunslinger

06-14-2000, 05:31 PM

Five The magnetic signature thing reminds me of speculation that the Soviet Alfa class submarines, with their titanium hulls, would be invisible to NATO magnetic anomoly detectors. I don't know if there was enough ferrous metal inside them to trigger the MADs, and I don't know if the titanium hulls were designed for that purpose, or for deep-diving capabilities. The Alfas were said to be able to make 40 knots.

I'm not in the SS (although a friend is leaving for it tomorrow), but I've read enough Clancy to know it's mainly for strength.

Gunslinger

06-14-2000, 05:41 PM

Thanks. I've also heard that the Alfas were theoretically capable of withstanding a lot of torpedo hits. Never got tested, though, I suppose. How much does that much titanium cost?

By the way, kudos to Boris for those sources on early towed sonars.

Costs a lot. In fact, that's the only reason they make their boomers out of steel i/o titanium--too expensive for a 900 foot missile boat. IIRC, Clancy mentioned that fact in either Hunt for Red October of SSN.

UncleBeer

06-14-2000, 06:10 PM

Tripler

06-14-2000, 09:50 PM

Every war movie I've seen with submarine warfare has scenes where the guys are whispering while trying to be undetected by the enemy.

Did whispering vs. talking really make a difference as to whether or not they were detected by enemy subs and/or enemy surface ships?

BTW, U-571 is pretty good war movie.

Okay, speaking as a military guy, *and* an engineer, I'd like to offer a few hints:

1. Every deck / surface / panel / doohickey is insulated against sound.
2. Even under general quarters and battle stations, the Skipper still has to give orders. You've also got regular boat functions (like torpedo loading and such) going on which generally make more noise than talking.
3. Sound may travel through water well, but remember that it has a refraction through the air/insulation, insulation/metal, and metal/water surfaces first. It's kinda like light. Stuff gets dampened and attenuated.
4. Whispering is still a mental response to the situation.

Just my $0.02

Narile

06-14-2000, 11:07 PM

Unclebeer, the Russian boomers are larger than American boomers, though I'm not sure how much longer. I do know that one Russian boomer actually has a swimming pool in it for the crew...Why? I have no idea.

Tripler, even with all the baffling, modern sonar mikes still have a pretty decent chance of picking up the spoken word. And the sound of the torp room is one of the things they listen rather attentively for. :)

mrblue92

06-15-2000, 07:30 AM

I do know that one Russian boomer actually has a swimming pool in it for the crew...Why? I have no idea. Are you sure it's not a pool/nuclear coolant tank? :)

"Very good, comrade. That extra eye will let you watch for capitalist spies."

Squid Vicious

06-15-2000, 09:05 AM

They would go into *silent* mode and it *was* silent! Everyone not on active duty had to lie silently in his bunk. Everyone else was extremely silent! They were listening to everything going on around them and sometimes it was whales and other natural stuff. The sounds were signature analyzed by computer to establish, origin, direction, distance etc. In spaite of everything it wa not always 100% clear.
There was a case of espionage a few years back when the russians got some info about how the USA makes their props so they are very silent, much more silent than Russian props are. This is very important as this prop noise allows sub detection.

I served aboard an Ohio class ballistic submarine (USS Henry M. Jackson) for 5 years so this subject is near and dear to me. First of all, during normal submarine operation, the boat is in "quiet" mode. The crew is allowed to go about business (talk, watch movies, play the stereo, run on the treadmill, etc.) normally. Loud noises such as dropping hatches, or banging on the hull will get you an ass ripping, but activity is pretty normal. If the order is passed to rig for "ultra quiet", then all extraneous activity is ceased. Off watch personel lie in their bunks, and all communication is done through sound powered phones. Specific arrangements of machinery is run in order to give a different sound signature (i.e. running the turbine generators at 59.5 Hz instead of 60 Hz).

All in all, Tridents are the quietest subs out there. I knew several sonar operators (sweater girls) who said that in order to find a Trident, they would look for a "hole" in the ambient noise. If they were real lucky, it might be a Trident.

It is true, as well, that the screw is the biggest noise maker on a boat. One of the reasons we were so quiet is that our screw was machined out of a solid piece of brass, instead of cast. The technology capable of machining something so large and precise, was supplied by Toshiba in an exclusive deal with the U.S DOD. Toshiba, in a fit of greed, in turn sold this technology to the Soviet Union. The Soviet subs became alot quieter all of a sudden, making our ability to find them more difficult. Toshiba later appologized, but I'm not buying it. In fact, I don't buy anything that Toshiba manufactures.

Umbriel

06-15-2000, 12:01 PM

A few comments on a number of the "sub"topics I've followed in this thread:

brad_d's discussion of the bias of subs toward passive sonar and surface ships toward active covered the topic pretty well, but it's probably worth stating specifically that anyone using active sonar has to have passive sonar in order to hear the results of their pinging, especially back in WWII and before, when they didn't have computers to do the interpreting for them. It was an art rather than a science, but there was a fair amount of information that could be gleaned by listening to hydrophones, above and beyond the mere presence of the enemy: Prop speed and engine noises could tell whether the sub/ship was going slow or fast, and potentially whether it was a merchant or warship. Subs could indeed hear the splash of depth charges, and ships might hear an oncoming torpedo (though their own noises could make this difficult, and certainly not something to rely on). A sinking ship would groan as its hull buckled, thus giving a destroyer some hint of whether it had killed a sub, and letting a sub know whether its first torpedo had done the job, or whether it needed to finish off its target.

As warinner pointed out, a number of subs were sunk by other subs in WWII. The British did indeed make it something of a priority, and sank several German and Italian boats (including, if memory serves, an Italian sub sunk off the coast of Malaya, while trying to haul rubber and other strategic commodities from Japanese territory back to Europe). Other nations also scored sub vs sub kills, including a Soviet sub mistakenly torpedoed by a Japanese sub a couple of years before the two countries got around to going to war. Almost all of the subs sunk in these engagements were hit while running on the surface, but the British hold the distinction of the only submarine kill of a submerged sub in history. Not quite the "luckiest shot in the world" cited by Jeff_42, but still pretty impressive, the Brit fired at a U-boat running at periscope depth which it had just seen submerge.

brad_d also mentioned the US Navy's magnetic exploder fiasco, which famously stalled our waging of effective submarine warfare in the Pacific. The Germans actually experienced similar dificulties at the beginning of the war (in their case, the defect was exacerbated by peculiar magnetic conditions due to iron deposits in the region of the North Sea and coast of Norway. Though they dealt with the problem more quickly than did the US, German subs apparently "counted coup" with dud torpedoes on several British Battleships and Carriers in the opening months of the war. It's been suggested that the abrupt loss of several British capital ships at that early stage might well have altered the course of the war.

Interestingly, while the Germans successfully used a primitive acoustic-homing torpedo in WWII (successful until the Allies found that floating a jackhammer in a liferaft behind a ship made an effective decoy), to my knowledge the only sinking of a ship by a submarine since WWII (the Argentine Cruiser General Belgrano, ex-USS Phoenix, by HMS Conqueror in the Falklands) was done with unguided torpedoes, due to technical problems with the new model homing torpedoes the British were trying to bring into service.

I've been fortunate to have the opportunity to visit a number of the WWII-era subs on exhibit around the US (Pearl Harbor, San Francisco, and Philadelphia). Cramped as they are, the hatches are relatively large, and they feature a lot of stainless steel, white paint, and light-colored linoleum in their interiors to try to "open up" the space. I'm not sure whether they looked the same way in WWII, or whether such fixtures were part of the "Guppy" refits that many of these subs underwent immediately after the war. In any event, its a wonderful contrast with the U-505, on display in Chicago, which is appropriately dark and menacing throughout. The hatches are small and round, and topped by "swing-through" bars, though larger portals have been cut through the bulkheads in deference to us lazy American tourists. The only sort of decor in evidence amid the dark functionality of it all, is in the Captain's bunk area. While not a proper cabin, it is fitted out with dark wood furnishings and polished brass fittings. Such are the privileges of rank.

casdave

06-15-2000, 12:35 PM

The Belgrano was sunk using the old mk6 torpedoes but the modern Tigerfish had first been fired and they missed.
The problem was down to the control wires that are trailed from the newer torpedoes, these wires are extremely fine and have to be palyrd out at just the right speed.

If you ask most submariners which subs are the quietest they will usually say the diesel/electric types, especially when dead in the sea submerged.
On one of the major exercises that takes place most years, Northern Wedding, a favourite ploy for the sub is to hide just below and behind a surface vessel where it is often only chance that the sub is detected at all.

It alway dissapointed me when I saw the size of the underwater missiles that subs use against us 'skimmers' when compared to the little things we had to fire back.These babies are big like 28 feet long and anti-sub one are around 7feet long. Seemed pretty unfair to me!

UncleBeer

06-15-2000, 01:54 PM

Umm, good point, Narile. I guess I forgot to consider the Russkies. That's what happens when you're a jingoist.

Anyway, from this page, http://www.armscontrol.ru/atmtc/Arms_systems/Navy/Submarine/Submarines_table_base.htm we find:

the Typhoon class is 175 meters, or 573 feet long
the Delta IV class is 167 meters, or 548 feet long
the Delta III class is "similar to the Delta IV class but slightly longer"
the Oscars, or Cruise Missile Submarines are 143 to 154 meters long

Still, nothing approaching 900 feet. While Tom Clancy is a pretty fair novelist, The Hunt for Red October is still a piece of fiction.

parkerea

06-15-2000, 02:19 PM

Not too long ago I saw documentary done on a US sub on patrol. A few things I remember are:

<<<snip...>>>

There was a case of espionage a few years back when the Russians got some info about how the USA makes their props so they are very silent, much more silent than Russian props are. This is very important as this prop noise allows sub detection.

<<<snip...>>>

Actually, the Ruskies were not told how the US makes quiet props, just that the US could easily hear the Russian subs, and their probs in particular. (The quote I remember was that before this they literally went around the oceans banging around, ignorant of how loud they were.)

Armed with this knowledge, the Russians went on an extremely effective mission to quiet down their subs. To make quiet props, they purchased sophisticated multi-axis milling machines from Toshiba, who blatantly ignored treaties by selling the Russians this technology. Even though the cold war is over, and Toshiba makes good laptops & TVs, I will never buy anything from them.

AnsaMan

06-15-2000, 04:36 PM

There was a case of espionage a few years back when the russians got some info about how the USA makes their props so they are very silent, much more silent than Russian props are. This is very important as this prop noise allows sub detection.

In certain strategic places, like the straight of Gibraltar there are plenty of listening devices to track any subs passing.

The United States has spent an enormous amount of money
over the years in the "black budget" to wire the oceans
for sound. It was successful.

The sound from the prop turning is cavitation in which
the turbulence from the prop creates low pressure areas
which give up their atmosphere in solution and creates
bubbles which make a lot of noise. Cavitation is
diminished by using certain prop designs, sizes, and
certain speed limitations on the prop.

sailor

06-15-2000, 05:15 PM

Interesting how this thread was dormant for over a month and suddenly resuscitates.

manhattan

06-15-2000, 05:21 PM

And on that subject, I'd like to congratulate this crew on your silence during this crucial mission. Thanks to your dedication and efforts, we were able to remain stealthy enough to complete our mission of getting this thread into the Threadspotting feature on the SD front page.

Good work, all!

sewalk

06-17-2000, 09:21 AM

Thanks. I've also heard that the Alfas were theoretically capable of withstanding a lot of torpedo hits. Never got tested, though, I suppose. How much does that much titanium cost?

By the way, kudos to Boris for those sources on early towed sonars.

Titanium is fantastically expensive (compared to steel) and generally prohibitive for shipbuilding. However, since the world's largest known titanium deposits are in Russia, the costs are relative. The Alfas were not the only Soviet subs fashioned from titanium; the Typhoon class of ballistic missle boats (subs are never called ships) are constructed mainly of it as well.

As far as the Alfa's resistance to torpedoes, the main concern was that it was fast enough to outlast a torpedo (Mk46=~45kts, Alfa=~40kts). This was one of the reasons the British designed their Spearfish torpedo with a top speed of at least 50 knots. All modern torpedoes use a shaped-charge warhead capable of penetrating more armor than is carried by any warship today. There was major concern about the Typhoons, since they are double-hulled and the dead space between the hulls disipates the energy of the warhead. The Typhoon is a huge boat (800+ ft) and even one good hit would probably not be enough to sink one. Add the insulative effect of two titanium hulls and American and British sub skippers would probably be prepared to fire three or four shots at one to get a better chance at a kill.

One further note about the Alfa: they used a revolutionary reactor design which turned out to be hellishly difficult to service. The last report I saw said that all of them had been laid up alongside in port for several years and that none were servicable any more. The Russian fleet is a pale shadow of what it was ten years ago.

StompyGodzilla

06-18-2000, 07:04 AM

There was also a "Director's Cut" version of Das Boot, which actually is the only version I saw. I'm pretty sure it was dubbed.

About a week ago I watched the Director's Cut of Das Boot on DVD. Best settle in - it's three and a half hours long.

They took full advantage of all the niftiness that DVD allows with soundtracks and/or subtitles. You can hear the audio in English, German or Spanish, and you can see subtitles in English, Spanish or French (or none at all).

We chose German sound with English subtitles.

They sell it at express.com, among other places.

Yeah, but something weird is going on there, 'cos that version varies from the director's cut that was released on video some years back, at least if you watch it with the English subtitles. Notably, the language has been tidied up. Irritating. In the original Director's Cut version I saw, you had that Nazi-guy complaining to the captain about the sailors on the side of the road: "It was most extraordinary. They... they..." and the captain smiles and says, "They pissed on you? Me too." On the DVD version, that line is changed to "They initiated you?..."

Not quite the same, somehow.

I noticed several other minor changes of the same nature, which frankly made me want to go learn German so I could watch one of the finest films ever made exactly how the director intended.

Stompy

Rich G7subs

06-18-2000, 10:51 AM

I was on an ancient ((by todays standards)) 637 class fast attack Sub.Most submarines are tracked and identified by sound frequencies the sonar girls called "tonals".American Frequencies were around 60 Hz...europeans around 55-57Hz.These Tonals were produced mainly by electrical gear,pumps,turbine generators..etc.Transient noise was sometimes heard(hatch slammings,etc)...but hard to track.You'd just get a relative bearing from a transient sound.Tonals could give you course,speed and bearing by the way the freqs changed as the sub closed or opened in distance.((called the Doppler effect)).So,IMHO, I don't think whispering,even if it could be heard,would cause much damage.

Gunslinger

06-18-2000, 05:35 PM

Just a minor point. Ballistic missile submarines are not 900 feet long. This from the U.S. Navy website:
General Characteristics, Ohio Class
Builders: General Dynamics Electric Boat Division.
Power Plant: One nuclear reactor, one shaft
Length: 560 feet (170.69 meters)
Beam: 42 feet (10.06 meters)
Displacement: 16,764 tons (17,033.03 metric tons) surfaced; 18,750 tons (19,000.1 metric tons) submerged
Speed: 20+ knots (23+ miles per hour, 36.8 +kph)

Doh! Slip of the finger (on the 10-key number section on the right side of the keyboard). I meant 600 feet. Typhoons are bigger than our Ohios, though.

Semi related question: why are all subs (even 600+ ft boomers) always called "boat" and never "ship"?

Boris B

06-18-2000, 07:19 PM

The Russians did. (Of the six that were built, several have been discarded; three may stay in service as "test platforms".)

I believe you, Gunslinger, when you say it was a typo. You're right, Typhoons are longer than our Ohios, by 2.7 feet. (They displace 21,500 tons compared to 16,600 for Ohios.)
What's your excuse, sewalk?

I hear massive exaggerations of Russian submarines all the time ("the Akula has been clocked at 80 knots" - what, was it in free-fall? "the missile room is bigger than a football field" - bigger? ya mean, like, taller?) I just wonder where they come from. A masochistic desire to brag about the (ex-)enemy? Hmm. Italians (http://members.tripod.it/borghetto/typhoon.htm) do it too, apparently: "We know very well that the Soviet navy is today the most powerfull Navy in the world".

I don't believe the Typhoons had titanim hulls. Hazegray (http://www.hazegray.org/worldnav/russia/submar.htm) mentions several types of Russian subs with titanium hulls; Alfa and Sierra classes are among them, Typhoon is not. I have seen plenty of information on Typhoons, and none of them has asserted that they were made of titanium.

Interesting question, Gunslinger. My guess is that it is tradition; the first several generations of submarines were quite tiny, especially to navies used to looking at dreadnoughts. Also, people expecting "ships" to be on the surface (unless something has gone seriously wrong).

stuyguy

06-19-2000, 09:47 AM

So after watching this Q accumulate nearly 3,000 views and 68 replies, I figured, Okay, let me see what all the fuss is about.

Kinda interesting, I thought after I read the whole thing... but nobody answered the best question on the thread! egkelly wrote:

"For all you WWII sub buffs-in the movie "DAS BOOT", there is a scene where they take a deep dive (the depth gauge reads in the RED zone. At this great depth, they hull starts making creaking noises as it contracts under the pressure-then you hear sounds like rifle shots-the bolts securing the hull plates to the frame start shearing off-is this true? I've never heard of any WWII submariner reporting such a thing-seems to me that this the last thing you would hear before the sea rushed in!"

I want to know this too! Does this happen, or is it just Hollywood bunk?

__________________________________________

Incidentally, a friend of mine who saw U571 sez that EVERY submarine movie he's ever seen has the same three scenes and they just mix up the order:

1. the go-too-deep scene
2. the oh-no-here-come-the-depth-charges scene, and
3. the let's-fool-'em-with-debris-out-the-torpedo-tube scene.

He's right.

Gunslinger

06-19-2000, 10:58 AM

I'm pretty sure that the Typhoons are plain ol' (as plain as these kinds of things get, anyway) steel. Titanium's too expensive and hard to work with on that scale. Besides, when you get that much of it, steel is strong enough.

cornflakes

06-19-2000, 03:27 PM

Semi related question: why are all subs (even 600+ ft boomers) always called "boat" and never "ship"?

Gunslinger, I had the impression that a ship was a boat that was big enough to launch another boat. Could subs be considered boats because they don't carry launches or because they can't release a boat underwater?

Gunslinger

06-19-2000, 03:38 PM

Subs can launch smaller boats--for example, there's a rescue vehicle that can be carried down and launched from a sub, and they "deliver" SEALS and their boats...

cornflakes

06-19-2000, 03:41 PM

Scratch one pet theory...

Gunslinger

06-19-2000, 05:35 PM

I always thought the "boat" thing was just because submariners are...umm...a few nails short of a keg (IOW, right up there with paratroopers on the crazy list).

sewalk

06-21-2000, 01:56 PM

Gunslinger

06-21-2000, 03:28 PM

The use of the term boat to describe submarines may be partially inspired by the derisive term "pig boat" which was used by surface types in the pre-nuclear era to describe subs. A closed cylinder full of diesel engines and sweaty men would have a certain aroma, I'd imagine.

Old sub joke: Q. Surface sailors call submariners "bubbleheads". What do sub sailors call surface sailors?
A. "Targets" :)

Rodd Hill

06-21-2000, 05:34 PM

Umbriel said:

Other nations also scored sub vs sub kills, including a Soviet sub mistakenly torpedoed by a Japanese sub a couple of years before the two countries got around to going to war.

On October 11, 1942 (Tokyo date), the Japanese submarine I-25 spotted two submarines on the surface, about 800 miles west of Cape Flattery, WA. Assuming they were US, the Japanese captain (Tagami) fired his last torpedo, and hit the Soviet sub L-16.

Interestingly, a Japanese torpedoman, one Aizawa, reported that the explosion was terrific (the range was only about 500 yards), and that the blast cracked instrument glass, light bulbs and even the porcelain toilet bowls on board the I-25!

There was one USN casualty in the action: a Russian-born American citizen, Chief Sergei Mihailoff, joined L-16 at Dutch Harbour, Alaska, as an interpreter.

The Japanese reported one US sub sunk, and did not learn the true identity of the Soviet sub until after the war.

Source for the above Silent Siege by Bert Webber.

BigGiantHead

06-21-2000, 07:23 PM

I've been in the US nuclear sub fleet for over ten years now (two Tridents and an older missile boat) - in fact, I'm sitting not 200 yards from one as I write. I'd just like to say that this is, by and large, a very well-informed and rational discussion. That said, here's my fill-in on a few points:

High-speed Alfas:
Yup, 40 knots might have saved them for a while. But since 1972, when they deployed the Mk 48 torpedo (see http://www.chinfo.navy.mil/navpalib/factfile/weapons/wep-torp.html), the top speed of that fish has been, well let's just say a good bit faster. And when the Advanced Capacity (ADCAP) was introduced about a decade ago, that raised the bar to a whole lotta bunch faster. 'nuff said - I could get in trouble here.

Titanium hulls vs. multiple hits
The way modern fish warheads work is primarily by exploding underneath the hull of the victim (as pointed out by brad_d). However, the intent is to vaporize not the metal hull itself, but a large void of water out from underneath the keel of the target. Suddenly, the middle portion of it lacks a great deal of support, is buoyed up mainly by the ends a good distance away, and - kKrracKK!! - breaks in twain, allowing the innards out and the water into the people tank, titanium or no.

Ricocheting bolts at depth
Assuming these bolts were holding back the pressure of the sea itself, the next sound might be an inrush of water. But modern designs are very careful to be sure that anything that will see submergence pressure is held together by welds only. No bolts to go flying around. What may be happening is the distortion of the hull's shape by pressure causing bolted-together frames, decks, etc., shear past each other far enough to snap those bolts. And, yes, the hull does distort. One US boat suffered enough of a peace-time accidental depth excursion that when it came back to port all the frames along the keel could be seen through the skin of the hull, like ribs on a starving dog.

Disparity in missile size
Casdave said:
It alway dissapointed me when I saw the size of the underwater missiles that subs use against us 'skimmers' when compared to the little things we had to fire back.These babies are big like 28 feet long and anti-sub one are around 7feet long. Seemed pretty unfair to me!

Sorry, pal, but those 44-footers aren't for shooting at YOU. They're for raining hot nuclear death on the guy 4,500 miles behind you. To shoot you we use the standard 21-foot Mk 48 torpedo, not missiles.

So there's my mini-SD for all you Teeming Landlubbers.

P.S. It's true about Toshiba. I, too, will never give them another dollar, if I can avoid it. Tell your friends and neighbors.

sailor

06-21-2000, 07:57 PM

>>EVERY submarine movie he's ever seen has the same three scenes and they just mix up the order:

1. the go-too-deep scene
2. the oh-no-here-come-the-depth-charges scene, and
3. the let's-fool-'em-with-debris-out-the-torpedo-tube scene.

Then there's the having to submerge so fast they barely have time to close the hatch and a load of water comes in and also the typical periscope scenes: up periscope, scan the horizon, detect a ship, ask the next guy if he also believes it to be an enemy ship, ok, prepare torpedos, torpedos ready, fire, etc

when I was a kid I always found these orders relayed like this kind of comical. Skipper says "prepare torpedo #1" and ten men relay the order down the sub to the guy at the tube who says "torpedo #1 ready!"and the same ten men relay it back! You'd think they could have a telephone and leave those men on shore if all they're good for is repeating orders. Or if telephones do not work under water maybe train parrots...

Revtim

06-21-2000, 08:00 PM

Thanks for all that cool info, BigGiantHead!

The part about the warhead being used to void the water was particulary interesting. A question though: what is there instead of water during the explosion? The gasses from the explosion? Vacuum? Gasses coming out of solution from the sea water?

parkerea

06-21-2000, 08:47 PM

<<<snip...>>>

Titanium hulls vs. multiple hits
The way modern fish warheads work is primarily by exploding underneath the hull of the victim (as pointed out by brad_d). However, the intent is to vaporize not the metal hull itself, but a large void of water out from underneath the keel of the target. Suddenly, the middle portion of it lacks a great deal of support, is buoyed up mainly by the ends a good distance away, and - kKrracKK!! - breaks in twain, allowing the innards out and the water into the people tank, titanium or no.

<<<snip...>>>

Brilliant -- I never would have thought of that. Have you ever done the "break a bottle with your bare hands" trick? (Bear with me -- this relates.) Take an empty bottle, preferably a thin walled one, and fill it almost to the top with water. Strike it quickly and strongly, and I mean strongly, straight down with the heel of your hand, and the bottom pops out. How? If you hit it fast and hard enough, the bottle accelerates downward faster than the water, leaving a small vacuum filled void between the bottom of the bottle and water. For that instant, 14.7 psi of air pressure is forcing the water downward, so it rushes down towards the bottom of the bottle, filling the void. When the water reaches the bottom, the water is traveling significantly faster than the bottle itself, so it slams into the bottom with a lot of momentum, but water will not compress, and glass will not stretch, so something has to give, and the bottom pops out.

You have to hit the bottle really hard. I have bruised my hand many times trying, but it does work. It is most impressive after you have finished off a bunch of cold ones with your friends. Of course, do this over a trash can.

I wonder if the torpedo action is similar -- the explosion creates a huge void in the water beneath the sub. The water rushes back in, with a heck of a lot more than 14.7 psi to accelerate it. (I assume we are at several hundred feet here, so if my memory is correct and there is about 3 atmospheres for each 100 feet, we should be talking 200+ psi.) The impact under the sub would be significant.

Question: do torpedos used against surface ships use the same technique, or do they go for direct impact? If so, it might imply my idea is correct, since the hulls of surface ships routinely span long distances between crests of swells in heavy seas.

Hmm. We seem to be digressing slightly from original "whispering" thread...

Gunslinger

06-21-2000, 10:26 PM

when I was a kid I always found these orders relayed like this kind of comical. Skipper says "prepare torpedo #1" and ten men relay the order down the sub to the guy at the tube who says "torpedo #1 ready!"and the same ten men relay it back! You'd think they could have a telephone and leave those men on shore if all they're good for is repeating orders. Or if telephones do not work under water maybe train parrots...

It does sound funny, but it also makes absolutely sure nobody f#@%s up.

Gunslinger

06-21-2000, 10:30 PM

BigGiantHead

06-21-2000, 10:38 PM

Actually, parkerea, I answered with a hit against a surface ship in mind. I suppose the difference with regards to weather crests-and-waves must come from the suddenness and shockwave factor. But presumably, your explanation also plays into both surfaced and submerged hits. And, yes, 3 atm./100 feet is about right (we use 44 lbs).

And you're right about losing the thread.

'slinger is also right about gases/steam.

We're all right! Isn't that great?

Umbriel

06-23-2000, 08:27 AM

Re: BigGiantHead's discussion of modern torpedo theory:

Titanium hulls vs. multiple hits
The way modern fish warheads work is primarily by exploding underneath the hull of the victim (as pointed out by brad_d). However, the intent is to vaporize not the metal hull itself, but a large void of water out from underneath the keel of the target. Suddenly, the middle portion of it lacks a great deal of support, is buoyed up mainly by the ends a good distance away, and - kKrracKK!! - breaks in twain, allowing the innards out and the water into the people tank, titanium or no.

This effect is, of course, what the notoriously defective magnetic exploders of early WWII US and German torpedoes were intended to achieve.

The Royal Australian Navy website has a rather spectacular set of photos and diagrams illustrating the principle, in the context of a live fire test last year in which the new diesel-electric sub HMAS Farncomb sank a decommissioned Destroyer Escort.

http://www.navy.gov.au/8_archive/news/rel15-06-99.htm

egkelly

06-23-2000, 08:44 AM

And another one for all current submariners:
those new closed-cycle diesl-electric subs 9that the French and Swedes have)-how quiet are these? (I assume with their diesls shut down, they make less noise than a nuclear sub). Also, becasue they carry liquid oxygen, they can stay submerged for several weeks. Are these a threat to our subs?

Wallrat9

10-24-2000, 05:42 PM

Ok so let's pretend that I am an ex-navy sonar operator. Now I might know a thing or two about the U.S.'s or even Russia's modern day sonar capability. But considering how some of this information may be considered...uh, sensitive, I'm sure you'll get the idea when I say I'm gonna make up a story.

How sensitive are modern hydrophones?
Well there was this fairy tale about some happy little bubbleheads hopping into their submarine and pulling out of thier port on the extreme northeast portion of their country (i.e. Alaska area). Well these little fellows had no idea that Big bad Mr. Sonalyst was listenning to them...from hydrophones off the coast of California. You see boys and girls, water conditions change, and on clear days you can actually hear sounds thousands of miles away. Not only did Mr. Sonalyst hear them, but by detecting harmonics caused by machinery and propeller imperfections, he was able to determine exactly which sub our friends were in - right down to the name of the boat.
Ok so this was a stationary hydrophone not attached to a ship or sub, but sitting on the sea floor. It is true that own ship movement affects your ability to detect underwater contacts. Basically the faster you are going, the less chance you have of hearing the bad guys. This applies to hull mounted hydrophones as well as arrays (hydrophones towed behind the vessel).
One of the biggest indicators in locating modern subs because they're so quiet, is listenning for machinery harmonics or transient noises, the latter of which includes all the weird sounds a submerged metal tube full of people might make. Mostly this entails bow planes, rudders, and normal stuff like that. But I've heard of subs actually being found because somebody heard a noise that didnt belong out in the open ocean (wrenches dont clink when they sink usually).

Russia has good subs, but ours are better...right?
Sorry folks. They've got us on that one. The country may be broke, but they still have a fleet of faster, quieter, deeper running, more advanced subs. I heard somebody mention that the Alpha class can withstand mutiple torpedo hits due to its titanium hull. Well you're almost right. The Alpha is a hunter/killer, or fast attack sub. It's the quietest, fastest, and deepest running sub in the world. But it isn't designed to withstand multiple torpedo hits. Actually your thinking of the Typhoon (sub featured in The Hunt For Red October). The Typhoon is your baby killer, a ballistic missile boat. This bad boy has 2 hulls whose sole purpose is to allow the boat to withstand several direct torpedo hits while it continues to fire off its nuclear missiles. As you can imagine, this boat is huge, completely dwarfing our ballistic missile boats.

Where can I get me one of those Typhoons?
Try under the polar cap. SSBN's (ballistic missile submarines) don't like to be found by anyone. They [Russian and American] usually hide out under the polar ice and wait for word to fire their nukes off. The Typhoon even comes equiped with shrouds around its twin propellers to help break through the ice. On word from command, they prepare the nukes, surface the ship, and launch enough firepower to wipe out most major U.S. cities - and thats just with one boat. And you thought the cold war was over.

Bad Russians! Let's get em!
Actually Russia isn't much of a threat. Its an understood agreement between us and them that neither one of us would win in a nuclear war. The real threat lies in Russia's technology and poor economy. When you're a country and you're hurting for cash, you start looking around for stuff to export. Well Russia had a whole fleet of old subs that were just rusting away, so why not sell them to the highest bidder? Enter Iranian officials, purchase sub, send crew (comprised of political officials sons) to Russia for included training, and watch as the sub takes off on its maiden voyage under new management. It's just a pity that those darn Iranians forgot to close the hatch when they submerged - chalk one up for ditsy driving. Enter mourning Iranian officials, purchase 2nd sub, send 2nd crew, and recieve word from Russia that the crew is a bunch of morons and the sub will be delivered on land (got some great satellite footage of that one).

Old subs=noisy and primitive=no threat to us...right?
Let's compare our old diesel engine powered sub to our new, high tech nuclear powered sub. The nuke can go down and stay down for as long as the food supply lasts. It's fast too, and runs deep, and most of all it's quiet - very hard to detect. Ok so now here's our diesel engine powered sub. It runs near the surface will it uses its diesel engine to power its batteries - loud as hell! Then, batteries full, it shuts off its diesel, dives down, and runs off of battery power. Sure it can't go very fast or very deep, but guess what? You can't hear the damn thing!!! An old boat running on battery is quieter by far than a modern day Alpha class. Case in point: Cuba is out cruisin in their new diesel boat, makin a ton of racket, then they dissapear. Three days later they're picked up returning from the coast of Florida (who needs rafts?). Always a bad sign when you lose a sub your tracking.

Ok that message was entirely too long and my ass is now swollen. I'm off to go make up stories in real time. Remember, everything you've read here was made up, or was it? I can never remember.

-m

Boris B

10-24-2000, 10:32 PM

What Typhoons? You mean the ones that are all out of service?

astro

10-25-2000, 12:25 AM

Originally posted by Wallrat9
Ok so let's pretend that I am an ex-navy sonar operator.
Remember, everything you've read here was made up, or was it? I can never remember.
-m

Per your missive, how is Russian submarine technology so advanced and better than ours if their electronics and technological infra-structure is a generation or two behind our own. Or is this more capitalist lies?

BTW I have a MK XII-3 torpedo gyro from WWII (I think) Marvelous piece of metal engineering. Still spins seemingly forever on just a little push.

Umbriel

10-25-2000, 12:39 PM

Wallrat's assertion about the Typhoon's damage resistance doesn't really have much to do with the technological advancement of Russian subs relative to our own. A Typhoon would have a better shot at withstanding damage by virtue of its sheer mass and double hull. This has been the cliche Russian/Soviet design philosophy for most of recorded history: Build everything like a tank -- aircraft, shoes, whatever. It certainly has its advantages in a setting where quality control is marginal, maintainance questionable, and training almost non-existant. However it has costs in terms of effectiveness and versatility.

Certainly the Soviets/Russians expended a lot of effort in the '80s and early '90s in trying to catch up with the US in the quality of their submarine technology. By means of espionage and questionable purchases of technology from countries like Norway and Japan, they quieted their subs considerably. The latest Akula and Sierra model SSNs are widely rumored to rival US subs in terms of stealth, and the Kilo class diesel subs actively sought by countries like China and Iran are no doubt that much more formidable because of those efforts.

That said, I haven't heard much about the state of Russian detection technologies, weapons, and other submarine systems, probably because they are harder for outside observers to evaluate. While I'm sure that advances in off-the-shelf computer and electronic technologies have helped them, it's difficult to say how agressively or effectively the Russians have pursued these fields. The use of liquid-fueled rocket-propelled torpedoes which came to light in the context of the Kursk sinking indicates to me that the Soviets/Russians were willing to pursue radical concepts in the hope of achieving an edge. This may not always have been the best use of their resources, however, and may have caused more problems than it solved.

The woeful state of Russian industry today can't be helping the quality of their subs. It remains to be seen whether the Kursk sinking was the fault of crew or equipment, but I'm sure that relatively casual attitudes toward safety in both contexts contributed. Foreign purchasers of such equipment do so at their peril, and with the further handicap of reduced familiarity with systems.