Can someone give me a list of army jargon and phrases and thier definitions?
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It depends on what kind of infrared camera you plan to use. Thermal infrared can see body heat, like this:Unfortunately, it can’t see through water. Also, it only works on warm-blooded animals, like birds and mammals. Even if it could see through water, the shrimp would still be invisible. Thermal infrared cameras are also expensive.Then there’s near infrared (NIR). All normal digital cameras can see NIR except that they have a built-in filter to block it out. The cheap ones, including the ones built in to cell phones, don’t have the filter, so they can see NIR plus visible light.To see the image on the right, you would need a filter to block out the visible light and just let the NIR through, probably something like a Wratten 87.I don’t know if this would work better than just regular visible light.
If a submarine hits an underwater mountain?
So i was looking at pictures of the USS San Fransisco after it ran into an underwater mountain and it was pretty banged up, i mean, there was body work missing. So i was wondering, on submarines, do they keep the compartments closed and locked until you need to access them or do they auto close and lock on there own when some one pushes a button. If they had them open, even by the time they would of closed it would of flooded, and im guessing that they keep them locked all the time, so only those few compartments flood.
The Nature of "Sound?"?
I always thought it had something to do with being a fake blonde. Both Buddy and Ric have dyed hair, so it was supposed to be some kind of an in joke, that they were natural blondes, when in reality they were both brunettes. Only one way to really tell if they are "natural" ya know. lol
There is no “Typical range”Unlike radar with which radio waves follow a pretty predictable path through the air… Sound waves through water are much more unpredictable. There are all manner of variable that factor in to what is called the theoretical Range of the Day. And those conditions change from one moment to the next. Temperature, depth, salinity, currents, background noise, Animal life, other maritime traffic…And that is not even considering the difference between different Sonar equipment, much less individual installations of the same equipment in different classes of ships. All of which impacts performance.Also you must factor in the noise level of the target if Passive sonar, or the size and sound reflectivity of the target if Active Sonar.A quiet target very close in could sound louder than a loud target very far away.Or a very loud target at moderate ranges could completely mask a quiet target from detection closer in.Is the signal of detection coming in Direct path? Bottom Bounce? Above or below the Thermocline? In a deep sound Channel? Via Convergence Zones?What?To go beyond this to give you any more concrete answers than that would get into information that is highly classified.Are you asking for Classified Information?
Can submarine's sonar pick up divers? How small of an item can it detect?Not by design. Passive sonar systems are designed to locate machinery noises and transients expected from enemy ship.Active sonars onboard submarines are not fish finders. They are not for searching the close locus around the ship but for detection and prosecution of targets at distances that are consistent with modern naval warfare.In the open ocean there are no divers. In the open ocean the best way to deter divers is to keep speed above 2 or 3 knots. My experience onboard a SEAL delivery Sub is even a few knots of headway made it very tough to operate in vicinity to the sub. Your mask keeps flooding and requires near constant clearing… Understand that is probably the slowest a sub can go without shifting their ships control party to different procedures and systems ( in some cases) to hover.In port, it is the port’s responsibility to provide whatever safety requirements are necessary to ensure swimmers cannot access the ships. Things I’ve seen were anti swimmer nets, or even having active sonar systems hammer away at the water - which is incredibly hurtful and disorientating to the divers in the vicinity.In short, US subs do not pull into a port that even has a chance of being vulnerable.
Yep. Active sonar detects contacts by bouncing a ping off the hull of the other sub and listens for the return.There are other factors like the frequency of the ping, the sound velocity profile (which affects what path the sound takes both directions), spreading losses, scattering losses, the reflectivity of the other sub’s hull, the sensitivity of own ships sonar and the ability of the sonar gang.Some places have an extremely strong velocity gradient and higher frequency sounds tend to dive for the bottom and never reach the target.The entire problem is basic physics, but it’s cool to see it in use.
Why is the speed of sound faster in solids and liquids than in air?
Yes, sound travels faster in denser materials. The reason it's not so obvious is that sound tends to bounce or reflect off dense surfaces, so little energy gets passed in to them from sound generated in air. Sound waves that are actually generated underwater - eg. Whale song, Sonar systems - can travel vast distances, much more so than in air for the same volume. You can get underwater speakers for background music in swimming pools, and they need tiny amounts of power compared to outdoor systems, as sound travels so well underwater. Ultrasonic signals are also used for underwater communications. A system with half a watt of (ultrasonic) audio output can have a range around 500m underwater - that's about the same sound level as a loud transistor radio or moderate TV volume. And yes, technically your neighbour would hear the TV first, by thousandths of a second, if you were both exactly the same distance from the loudspeaker and they were hearing it through a solid wall.
Can an EMP travel through water and affect electrical systems underwater, such as submarines?
Although there are alternative methods to generate an EMP besides a high-altitude nuclear detonation, EM waves do not propagate through conductive material, like water, except at very low frequencies (skin effect). That's why radios don't work on submarines when they're underwater and why they use SONAR (accoustic) instead of RADAR (EM). Any amount of EM energy that was able to propagate at lower frequencies would go straight to the earth since the ocean acts a one, enormous electrical ground. Even if it could propagate and hit a submarine, the hull would act as a Faraday cage and prevent any EM field from forming inside, protecting its electrical systems.