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What is the impact of storms on submarines?

  1. Apr 11, 2017 #51
    Were you ever deployed to a submarine that did not use nuclear plants?

    What kind of fish were in the aquarium and how were they dying?

    Did you ever meet Admiral Rickover? :wink:
     
  2. Apr 11, 2017 #52
    Never served on a diesel electric. they didn't have medical officers. Polaris had medical officers had medical officers since if they surfaced their targets had to covered by aircraft. Who knows about the fish we didn't carry an icthiologist. As far as Rickover--no but every nuke medicine chest had his prescriptions including mine.
     
  3. Apr 17, 2017 #53
    1. Hello, thank you for accepting me in this forum. I live in Key Largo and I have found interesting news about hurricane wave energy. When the Spiegel Grove was sunk as an artificial reef off the coast it came to rest up side down in 135 feet of water. After much effort the wreck was finally rolled on to it's side. Then hurricane Dennis came through in July 2005 and rolled the ship onto it's bottom. It would seem that the hurricane can reach down and roll a 600 ft ship that weighs what, 30,000 tons and is in 135 feet of water.
     
  4. Apr 20, 2017 #54
    I'd suppose there may be problems when a storm drives a surge over a ridge or such that would normally be too deep to matter. Like the 'Clear Air Turbulence' that toss aircraft about down-wind of mountains, the resulting 'internal waves' could be very unpleasant. Another issue is storm-driven mixing of cold bottom water with warmer mid-waters, with unhappy effects on trim and buoyancy...

    FWIW, I've read of pressure pulses from submerged volcanic eruptions causing VERY LOUD 'thumps' on passing ships that could easily be mistaken for groundings, debris collision or whale-strike. IIRC, this has been suggested as a plausible explanation for the Marie Celeste abandonment. A naval sub must always consider the possibility of 'hostile activity', of course, of course.....
     
  5. Apr 21, 2017 #55
    Have you ever been to Jules undersea lodge or Marinelab?
     
  6. Apr 23, 2017 #56
    Das Boot, both the book and the film.
     
  7. Apr 23, 2017 #57
    As a former submarine sailor, I can relate anecdote but not explain the physics.

    First, the main effect it has is to make it nearly impossible to detect another nuclear powered submarine (since both present just broad white noise type traces on the sonar displays.

    Second, and to your point, running at ~300' in the Irish sea, sea state 6 topside and the boat did a very slow roll to starboard, all the way to 7 degrees, then just as slowly righted itself.

    The hull is round or roughly symmetrical except for the sail. Apparently some very strong current (whether storm related or not I couldn't say) hit us, tipped us to where a few people started to get bug-eyed, and then we continued on our way as if nothing ever happened. It was a completely smooth transition, we were traveling in a straight line, we just slowly leaned over and then slowly righted.

    As you get near to the surface you get erratic behavior for the same reasons two ships will be drawn together into a collision if they run side-by-side - reduced wave action on the side nearest the other ship results in lower pressure. On a submarine you have pressure effects from the wave action acting on the top side of the boat. On a boomer (FBM or fleet ballistic missile) the superstructure is flat on top, the pressure hull is round everywhere else so it's not a symmetrical setup.
     
  8. Apr 23, 2017 #58
    Red October was so unrealistic it doesn't bear mentioning. Me dear mudder demanded that I read it when I was between FBM patrols because she "had to know" if it was real or not.

    Das Boot the movie captures some of the intensity of the "WTH as that?" feelings, though of course today the boats are pretty spacious.

    Scariest things these days are fishing trawlers and seismographic expeditions. Trawlers will often turn off their engines to save fuel and the first hint you get that you're under one is a long, slow scrape of a steel cable against the outside of the hull. Siesmographic expeditions sound like fishing trawlers or small freighters until 50 pounds of explosives goes off in close proximity to your left butt cheek.

    Come to think of it probably the most altitude I ever achieved while sitting on the sonar stack was after about 2 or 3 days of heavy snapping shrimp (which sound exactly like bacon frying in a pan) a pod of pilot whales silently crept up on us, got right up to the conformal array of hydrophones (Lafayette class BQR-7) and went "BRAAeeeeEEEAAAAAAAAPPPP?" They played and squeaked and squawked for a good hour after that, but that fist one, I *swear* they knew exactly what they were doing and that they were going to scare the poop out of some poor schmuck wearing headphones.

    Most FBM patrols are simply "3 knots to nowhere", wandering randomly while staying away from shipping lanes. It you imagine boring, add in some mind numbing, stir in equal amount of tedium and monotony and then top it off with xmas eve 400 feet down in the middle of the north Atlantic then you too can experience an FBM patrol.Just don't forget to make the "bpththptpphthtph" noises just right and it'll be just like the real thing.
     
  9. Apr 23, 2017 #59
    Hey, get qualified :)

    CO2 scrubbers used an amine solution. Don't you remember all that from getting your qual card? :)

    I still remember the oolie questions and answers.
     
  10. Apr 23, 2017 #60
    #1 Psychological effects? Pretty much as expected. When you're on a boomer, which are the ones that stay submerged a long time, you're on a semi-regular schedule. You know you're on patrol for approximately x days and then back on shore for off crew while the other crew (blue and gold crews on each boat) has it out on patrol..

    Also when you get qualified in submarines (get your dolphins, which is about the same as a pilot getting their wings) the certificate says "Having proved himself under stress..." If there are sailors you don't trust your life with, you intentionally inflict stress on them until you're either comfortable that they can handle it, or until they break and end up on a surface ship. When there is a fire in a garbage can, that's your oxygen burning, you can't have someone around who will panic or run away.

    We broke one guy, he was a compulsive liar, including lying about performing periodic maintenance on survival equipment. As part of normal periodic training/exercise they shoot "water slugs" out the torpedo tubes, basically just cycle all the mechanisms and then drain the tube without actually loading a torpedo in it. Afterwards they have to dry the inside of the tube. He was volunteered to do it (as non-qualified sailors often get "volunteered" for dirty tasks) and while he was in the tube they closed the breech door. We could hear him screaming on the sonar array. He volunteered himself off the boat as soon as we got back.

    Two guys broke on their own, one was a very religious type who ended up making gibbering noises and had to be taken off, the other just decided he was leaving in mid patrol, just packed his sea bag and started climbing the forward ladder saying he was going home (we were several hundred feet down at the time)

    #2 Amine solution in the CO2 scrubbers. There was a CO burner, CO2 scrubbers, and oxygen generators, 2500A of DC current passed through seawater will make a fair bit of oxygen. There was a pump to discharge the hydrogen overboard. Initially they let it all out through a small pipe but then discovered that the hydrogen wake could be tracked from satellites under certain conditions, so they added diffusers.

    The reactor is one of the least scary things on the boat. You have flasks of pure hydrogen to "patch up" the water around the reactor (not a physics guy, I know the zoomies knock bits loose and they have to put hydrogen back in to make it go) which are pretty scary, and the gigantic oxygen generators with extremely high electrical currents and pure oxgygen in them. Then there are the huge banks of lead acid batteries down below all generating hydrogen gas as they get charged...there are some shipyard photos of one boat that was still being constructed when someone sparked in the battery compartment. Two decks worth of equipment and people was a 12" veneer stuck to the top of the pressure hull.

    #3 Sea life... depends on what you call problems. They make it hard to see where you're going.

    Snapping shrimp are frequent cause of problems, they like the thermal wake from the reactor and when you're on patrol you're just moving 3 to 5 kts so they can keep up. for a long time. They sound exactly like bacon in a frying pan when you're listening on the stack (most sonar is visual, just looking at digital or paper displays, but there are still important/critical cues that require listening)

    Sometimes sperm whales would discover the shrimp. They clop their jaw when they're eating shrimp. They're called "carpenter fish" because it sounds exactly like a gang of carpenters framing a house, sometimes the hammers happen to hit in sync, mostly they're random, but they're constantly banging. If they don't go away pretty quickly the boat has to go deep or speed up or both to shake them off. You can't hear well with all that banging going on, and you really don't want to deploy a towed array sonar while there are great big critters out there who might want to rub/scratch on it..

    Sometimes dolphins or pilot whales will visit and surf the pressure wave on the bow, but not very often (in the north Atlantic at least)

    Algae are probably the most problematic. Since the boats move very slowly on patrol, algae can turn the hull bright green if you're in warm water. That bright color can be seen quite a ways down by aircraft flying overhead.

    There's a story (apocryphal?) that during WWII the British submarine captains would surface and feed stale bread to the seagulls. Every time the seagulls saw a big dark shape in the water they'd congregate over it waiting for dinner. If the shore batteries knew there weren't any British submarines patrolling that stretch of shoreline and there was a big crowd of seagulls, they'd open up and shell the crap out of whatever it was the seagulls were seeing. If the story is true I imagine there were a few briefly surprised Germans betrayed by the seagulls.
     
  11. May 28, 2017 #61
    I have not really read anything about the topic until this time. But this is interesting for me. I have to read more on it or is there a video related to this topic?
     
  12. Jun 13, 2017 #62
    Picture the ocean as the atmosphere but with more momentum and able to store even more heat energy.

    It really is constantly changing, constantly in motion, and there are storms and gales and the occasional calm day.

    There are flows of fresh/less salty water from rivers and melting icebergs and ice sheets, great torrents from undersea vents and volcanoes, thermals as powerful as the ones that sailplanes ride in the atmosphere.

    I think it'd be a mistake to picture the ocean as this placid bathtub with just some churn on top. I think a better picture is the movement of moisture and wind that you see in the air...just wetter and below the waves.

    There are small organisms (can't remember what kind, can't find my cite either) that are genetically identical at both poles. They apparently ride the conveyor currents from one pole to the other in water that stays cold enough for them to survive.

    http://www.whoi.edu/main/topic/currents--gyres-eddies
     
  13. Jun 22, 2017 #63
    The depth the effect of a wave will be felt when inside a submarine is equal to 1/2 the wave length of the wave on the surface. IE if the peak to peak distance of the wave at the surface is 100m, the effect of that wave will be felt down to 50m depth. The wave form of a 'wave' as in as found on the open ocean, is sinusoidal. Therefore the form (shape) of the effective wave beneath the ocean is the lower half of a standard sinusoidal waveform. The bulk of the volume of that wave form is closer to its base line, in this case the surface of the ocean. Therefore the bulk of the energy contained within it is greater, closer to the surface. So in simple terms, the deeper you go, the less effect the wave will have until you reach the 1/2 wave length depth, when there ceases to be any effect. Incidentally, the effect felt is that the submarine surges back & forth with each passing wave.
     
  14. Jun 23, 2017 #64

    olivermsun

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    The 1/2 wavelength rule is a good way to think about the physics of the surface waves and their decay with depth. To answer the question of whether the waves will be "felt" inside the submarine (or whether the boat will be significantly affected), one probably also needs to consider the wave amplitude and period, as well as any compounding conditions such as mixed waves, shears, etc.

    FWIW, this is usually a decent approximation, but you commonly see some "peakiness" to the waves as the amplitudes get larger.
     
    Last edited: Jun 23, 2017
  15. Jun 23, 2017 #65
    The inferred query in the original question seemed to be, was the effect of a wave (or wave system) a surface phenomenon or full water column depth phenomenon. The two instances given, being during a hurricane or a Tsunami. The two examples being perfect examples of each event. The Tsunami is a full water column movement (transfer of energy) & a hurricane is a surface movement governed by the sinusoidal rule (with small variations due to mixed wave patterns etc).
     
  16. Jun 23, 2017 #66

    olivermsun

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    The tsunami is a shallow water wave, defined as a wave whose wavelength is significantly longer than the depth of the ocean, so yes, its motion is not significantly attenuated at depth (as seen from the 1/2 wavelength rule you mentioned in your post).

    I'm not sure what you mean by a hurricane being a sinusoidal surface movement. A hurricane is a storm. The seas generated by a hurricane can potentially be felt far from the surface, certainly at depths where a sub can be operating (as mentioned in at least one post earlier in this thread).
     
  17. Jun 23, 2017 #67
    What I was saying was the wave type induced by a hurricane is a sinusoidal waveform, at the surface. The effect of that waveform is felt down as far as 1/2 the distance between peaks of the wave form at the surface.

    A wave isn't a single waveform in reality. It is a composite pattern of waveforms overlaid upon each other. Hence the occasional larger than average wave often observed, when the peak of two or more overlaid waveforms synchronize at one location.

    A wave form in the open sea can have a peak to peak distance of hundreds of meters. A good example is the long rolling swell, which isn't normally considered to be a wave. But it is. It is these long swells which produce the deepest effects in the water column. (Dis-regarding Tsunamis for now)

    I am a submariner, in mini subs. I have spent thousands of hours in the zone where the effects of the waves above can be felt. The long rolling swells, often seen pushed in front of large weather patterns, penetrate the deepest. The short sharp waves caused by local wind conditions don't penetrate very far at all.
     
  18. Jun 23, 2017 #68

    olivermsun

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    We view the waves induced by a hurricane as a superposition of sinusoidal waveforms as a matter of convenience. As I mentioned earlier, deep water waves aren't exactly a superposition of independent sinusoidal waves, but it is an approximation that works very well in many cases.

    Glad to make your acquaintance! It would be cool to hear more about your experiences in submarining.
     
  19. Jun 24, 2017 #69
    Anything you'd like to know. No problem. From a practical perspective that is. My science on the subject is directly related to the day to day practical challenges involved in taking submarines & ROVs subsea.
     
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