Crusty Posted July 1, 2006 Posted July 1, 2006 You -might- be able to do that, even with the largest of EWRs ... but then, that's an entirely different style warfare, and once you go there ... ..someone has...and I cant off hand think why not again. sry a bit ot..but I have little faith in the powerfull containing themselves edit...to clarify Im not aiming the "doing it again" at any particular country..just some country repeating the useage of such stuff....phew. oo err...missus:animals_bunny: ** Anti-Pastie**
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 Don't even go there, Crusty. If you would like to continue in that line...how big is Okinawa, and how many US Marines died there? How many Japanese? Do you know how many Japanese divisions were sent to Kyushu? Just a hint, the numbers on Okinawa paled in comparison. Any idea as to the date the invasion of Honshu was planned...or the numbers of expected friendly and enemy casualties? BTW...the bombings of Nagasaki and Hiroshima, combined, killed 1/3 the number of Japanese civilians as the conventional, incendiary bombing of Tokyo in the prior year.
Crusty Posted July 1, 2006 Posted July 1, 2006 Don't even go there, Crusty. If you would like to continue in that line...how big is Okinawa, and how many US Marines died there? How many Japanese? Do you know how many Japanese divisions were sent to Kyushu? Just a hint, the numbers on Okinawa paled in comparison. Any idea as to the date the invasion of Honshu was planned...or the numbers of expected friendly and enemy casualties? BTW...the bombings of Nagasaki and Hiroshima, combined, killed 1/3 the number of Japanese civilians as the conventional, incendiary bombing of Tokyo in the prior year. go where?..you are reading more into what I said some country ..ok? ...some country could repeat what AMERICA did once..the fact AMERICA did it once, is just that....a fact, I personaly think it was wrong ok..now reel that neck in and dont ever think you can tell me where not to go oo err...missus:animals_bunny: ** Anti-Pastie**
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 You are asking "why not again"? Wasn't it a recent post of yours that went something like "M.A.D.?" Well...there's your answer. In case you didn't realize the point of the post you were commenting on, it was about using a nuclear SAM to down an F-22. This would have been worse for the population that SAM was meant to protect than the F-22s payload itself. If it came to that...well...the proverbial "gloves" would already be off. I like your all caps of America, BTW...I guess the fact that half my family is Japanese means nothing. Oh well. :thumbup:
tflash Posted July 1, 2006 Posted July 1, 2006 Guys, I am a little disappointed how difficult it is to stay on topic. If I'm right, we are discussing LIDAR in an F-22 context. [sIGPIC][/sIGPIC]
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 Actually, the discussion was about the F-22...period...and possible means of detection and defeating it. An honest question about using a nuclear-tipped SAM was asked, and answered...then it had to turn to politics. As for LIDAR...its a promising technology, but it is, at the moment, far too sensitive to atmospheric conditions.
Pilotasso Posted July 1, 2006 Posted July 1, 2006 Actualy a LIDAR can come in a large array of frequencies since it is an active laser sensor. You can shift the frequency to the ultra violet band and it can see through clouds. Of course this is all acadmemic since it will take decades to develop it to make it a feasible airborne sensor. Imagine fighters with a huge crystal ball at the nose. .
Weta43 Posted July 1, 2006 Posted July 1, 2006 - would give the pilots an excuse for some pretty fancy sunglasses :-) Cheers.
tflash Posted July 1, 2006 Posted July 1, 2006 Since Lidar is not a directly valid option, maybe this means that for the next 5 to 10 years you need strategic depth to defeat stealth and the global strike concept. Only a defender with a very large and deep territory like Russia and China can have a good EWR belt and use the described triangulation techniques to try to locate a stealth invader when it is already flying over its territory. It seems much more difficult for a nation like Australia, that has to look over an incredible huge area over sea to spot intruders far off-shore. I wonder what the performance of Wedgetail would be against stealth aircraft? [sIGPIC][/sIGPIC]
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 Yes...UV can see right through clouds...with a huge amount of attenuation, but the power would still be useable. Put a simple 1/8" thick piece of plexiglass in the beam's path...whoops...game over. Want cheap? Try regular glass...even worse. Cuts almost 500uW/cm^2 down to less than 2uW/cm^2...and all it has to do is be there. UV is also extremely sensitive to angle, distance, and destructive interference.
tflash Posted July 1, 2006 Posted July 1, 2006 Maybe this holds some promise: http://asd-www.larc.nasa.gov/lase/ This use of Lidar to study atmospheric conditions could pave the way to study atmospheric disturbancies, like a stealth aircraft that is passing through? [sIGPIC][/sIGPIC]
Weta43 Posted July 1, 2006 Posted July 1, 2006 What about this as a science fiction idea : Don't know what the radar frequency equivalent of a laser is called, but assemble a ground based coherent beam microwave with a power of about 10 MegaWatts Slave it to your EWR. Focus it to make the beam about 100m diameter (EWR is good to about that accuracy ? what's the wavelength of an EWR?) at the target range & keep the target in the beam. There would be about 1270 Watts per square meter landing on the target, which will probably do the target no good in itself, but if it's absorbing only 20 percent of the energy that's 250W/m^2 onto a thin skin - it's going to warm parts of it up quite nicely regardless of whether it's causing a return in a radar sense or not, then launch an IR missile at the toasy warm plane. Cheers.
Pilotasso Posted July 1, 2006 Posted July 1, 2006 By the time LIDAR comes into regular service, probably F-22's and manned fighter are going to be history by then. Its a cute technology but we cant still fool around with it much on ground much less in the air. BTW IguanaKing I didnt know the stuff you said about opacity of materials to UV. I never had optics. I guess these boards are good to learn from people in the know like you. Cheers! :) .
Weta43 Posted July 1, 2006 Posted July 1, 2006 'like a stealth aircraft that is passing through?' Tracking the water vapour could tell you where they've been, but not where they are.. Cheers.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 The microwave (assuming you are referring to actual microwave freuquencies) beam could easily be defeated by the introduction of water vapor between it and its target. Yes...microwave is how radar works...but it doesn't depend on microwave energy being able to create IR. If you expect this coherent beam to be able to burn through all of that...well...just make damn sure all of your guys are out of the way. Plenty of water molecules in the human body that are just the right size for a beam of that wavelength and power.
Weta43 Posted July 1, 2006 Posted July 1, 2006 'By the time LIDAR comes into regular service, probably F-22's and manned fighter are going to be history by then. Its a cute technology but we cant still fool around with it much on ground much less in the air.' It's already in service (that little bump in front of the canopy in the Russian birds in LO - that's got a LIDAR unit in it.) It's only extending it to BVR that's future technology, not putting it into service. UV is attenuated by silica glass, but to no where near the same extent by quartz glass & I think not by synthetic saphires either. It's quite do-able to make optics for UV lasers. Cheers.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 Pilotasso, my knowledge of UV radiation comes from my study of reptiles...there's no more purpose to it than that. I walk around with my UV meter testing EVERYTHING...EVERY material for UV transmission...I sometimes look like a bit of a geek. I even actually hear occasional negative comments...to which I think to myself..."Thanks...I wish I were there to see the suffering you'll be experiencing about 2 hours from now. NO SUNSCREEN!!! MUHAHAHA!!!". Thanks for the comment though.
Weta43 Posted July 1, 2006 Posted July 1, 2006 The Hz used for microwave TV repeaters is about where I was thinking. That seems to be able to get through the clouds OK. I realise radar works on a fairly short wavelength - whether or not it's about the same as that & officialy microwave - I don't know - your field not mine. The idea of using the microwave to generate heat/IR & defeat the radar stealth with an IR missile is the bit of it I was calling science fiction - the bit I just dreamed up. No - I wouldn't want to stand in front of it, but the fact that it might steam the pilot might count as an added extra from a military point of view.. Cheers.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 UV is attenuated by silica glass, but to no where near the same extent by quartz glass & I think not by synthetic saphires either. It's quite do-able to make optics for UV lasers. Sure, the transmission optics are quite doable....but a fact that can never be changed is that this type of laser can easily be defeated by a simple piece of clear, polycarbonate plastic...no exotic gems or materials required.
Weta43 Posted July 1, 2006 Posted July 1, 2006 By wrapping the whole plane in 5mm of polycarbonate? I think that might create a few problems of it own... Heat dissipation & creating enough static electricity to give the whole plane a nice blue glow in the dark might be two Cheers.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 The Hz used for microwave TV repeaters is about where I was thinking. That seems to be able to get through the clouds OK. I realise radar works on a fairly short wavelength - whether or not it's about the same as that & officialy microwave - I don't know - your field not mine. The idea of using the microwave to generate heat/IR & defeat the radar stealth with an IR missile is the bit of it I was calling science fiction - the bit I just dreamed up. No - I wouldn't want to stand in front of it, but the fact that it might steam the pilot might count as an added extra from a military point of view.. If you have enough RF in the microwave band to fry a pilot and cause him a fairly quick death at a given range...anybody else in that beam is going to die too...anybody between the transmitter and the fried pilot...well...its a guarantee. BTW...TV repeaters are LOS transmitters...and anything other than a heavy fog isn't going to have much effect. High power...and HUGE antennas. The same goes for cable TV vs. satellite TV...it all comes from the same source...but the cable company has enough money to afford the big antennas that can actually get a useable signal through heavy weather...the average "smart guy" with his "dish" has a whole 18 inches to grab what the clouds and water vapor haven't already destroyed.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 By wrapping the whole plane in 5mm of polycarbonate? I think that might create a few problems of it own... Heat dissipation & creating enough static electricity to give the whole plane a nice blue glow in the dark might be two Or, perhaps, just giving the entire aircraft a 1 mil coat of polycarbonate on top of its paint? Oh...wait...this is already done on many aircraft and cars, just to keep the sun's UV from destroying the paint. BTW...most aircraft already create quite a bit of static electricity...that's why they all trail thick bundles of high-impedance "wire" (static wicks) from the trailing edges of their control surfaces. Proper electrical bonding between said control surfaces, along with gear doors, flaps, etc....all weigh in on how successfully an aircraft can even communicate from 118-136MHz. As for higher freqs, in which a ground plane is required...forget about it.
Weta43 Posted July 1, 2006 Posted July 1, 2006 Yeah - but I guess the millitary really can afford a 150 foot tower & a feck off big transmitter ( probably quite big if they go with the MW laser thing) to go with their EWR, so the only person standing (sitting) in the way should be the pilot of the plane you're after. LOS is OK. LOS is a fairly long way if the target is 5000m - 10000m up in the air Anyway - I wasn't suggesting high enough beam strength to cause instant death ( though maybe a few nast burns just before the SAM gets there), just enough to raise the temperature of the aircraft skin enough to give it an nice big IR signature for the heat seeker winging its way in... Cheers.
Guest IguanaKing Posted July 1, 2006 Posted July 1, 2006 ...and, as I said earlier, converting microwave to IR on a receiver takes lots of power. That power, if its high enough to create significant heat in the airframe (significant enough to go beyond background) is going to kill the pilot, and ANYBODY who gets between the emitter and the target...yes...damn near instantaneously. Lower the power a bit to where it no longer generates that kind of heat in an airframe, and you just blind the pilot and any other human or animal between him and the transmitter. The REALLY bad thing about radar (microwave) freqs is that most of them are quite similar in wavelength to the width of the capillaries in the human (and other animal species) retina. These capillaries make excellent whole wave antennas, so transmitter power is definitely a concern in a theatre of battle where any biological lifeform is expected to function on its eyesight.
Weta43 Posted July 1, 2006 Posted July 1, 2006 Ahhh - I thought you'd misunderstood me & meant deliberately turning it into IR - with a receiver turning it into lectrickery & then powering an emitter -that took a lot of power - not just indirectly heating by causing eddy currents in the skin & struture - & I didn't mean that so I repeated myself. Re the capilary thing - You could always get the pilot to wear one of those tin foil hats so popular in the psych wards - put brail on the controls ... So - does 1.2KW/m^2 count as a lethal beam - my stomach turns & says yes ? -leaving aside the damage it might do to the pilot, & even assuming 40% is absorbed (because stealth planes have that nice radar absorbing coating) that's 480W/m^2 that's being absorbed by the plane & having to be dissipated - that's a fair amount of radiating somewhere in the spectrum - or is it?? Compared to heating through friction etc - don't know.. Cheers.
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