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Wouldn't this require the plane to know the position of the sub? And aren't ermmm sub meant to keep their locations secret? Undetectable?
US Navy boffins say they have developed a method which could allow aircraft to communicate with submarines using frickin' laser beams. Dr Ted Jones of the Naval Research Laboratory has developed methods of generating acoustic effects in water by firing laser pulses into it. According to the lab: Optical properties of water …
The phrase many "hundreds of meters [sic] through air" is the sort of equivalent of "up to 8GB" nonsense peddled by ISPs, and does not sit well with the following "aircraft high above the sea", which I would take to be a sort of AWACS operating altitude.
Also its disappointing to see early on that the acoustic effects of firing a laser into the sea are not the boom of the exploding (or imploding) vessel which I am sure the Americans would prefer. Still at least its a way to counter EvilCorp's sharks.
If they waited 50 years before deploying this technology, the "rafts of dead marine creatures floating in the sea" that were killed by this technology would not, without a post mortem, be distinguishable from the rafts of dead marine creatures killed by pollution. And eventually when the sea is devoid of all life, the subs would not be detectable at all.
having looked at laser induced cavities in water I'm aware of a few phenomena around this, the most interesting I believe to be the oscillating bubble. A cavity/bubble created by heating (that is the process we're talking about right?) the water expands whilst it is powered, then when the light stops, the surrounding water compresses the bubble. As it compresses the gas within gets hotter and after a finite compression it begins to expand again (though obviously not to its original size because of thermodynamic losses) and so on in an oscillatory fashion until extinct. Now with all these little bubbles popping up and down and changing size, and the fact it takes a little time (ms not ns or even near fs) I'm wondering if you could even transmit anything of worth.
OK you might squeeze a little data through such a method, but encrypt it and send anything of size/worth, doubtful.
Maybe a 220dB pulse could still give a detectable echo off even a stealth sub. And apparently the subs being stealthy use routes in known valleys in an attempt to be more discreet, so any such signal in the vicinity of one might set lights flashing. Anyway, it's not as if they're going to tell us any technical details about it, I was just supposin'...
Many years ago I read about a new communications system for communication from aircraft to submarines...using lasers!
The difference that time round was that it relied on the principle that blue/green lasers would penetrate oceans to a depth of several hundred meters as they are attenuated less than other colours.
As I remember it died a death because you would have aircraft circling the submarine position. Bit of a give away really - and no different to this 'new' system.
Let me get this straight. Let's say I am in a 688I (LA Class) attack sub when a P-3 or some other aircraft goes active via lasers to detect a Russian sub. I'm exposed by the same pulse, negating any advantage I had. One reason subs hate to go active is because it gives away their position. If I can go active and detect something 6000' away, I know that someone roughly 60,000' can pinpoint my position as I gave myself away.
Having an airdale give away a sub's position could be disasterous. Slow data rates and a few 220db pulses I can live with (better than the buoy or floating wire. Airdales going active and compromising our subs, bad. Better to do that in an area where our subs are known to NOT be in, and use skimmers' buoys to detect.
There's an obvious flaw looming..
If the efforts of the military are now focused on defeating international terrorism (is it just me that thinks of Crelm whenever they hear that phrase?) as organised by evil geniuses everywhere then all they need to do to cause chaos and disrupt submarine communications is to have sharks with frickin laser beams on their heads....