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    General Questions Thread:

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    GarryB
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    Re: General Questions Thread:

    Post  GarryB on Sun Nov 07, 2010 1:52 am

    Inlets and intakes are different.

    An intake is the normal way air enters the engine.

    Sometimes however the engine needs more air so the inlets are released and they get sucked open and let more air in. Or sometimes there is too much air coming in and they let air leak out before it gets to the engine.



    In the above picture you can see the inlets are closed because there is enough air getting to the engines through the normal air intakes for the takeoff.



    In this picture the inlets are open because the engines are in a low thrust setting and are probably not using all the air coming in the intakes so air leaks out the inlets to reduce the air pressure in the intake.

    At high altitude at low speed they will likely open to increase pressure.
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    Re: General Questions Thread:

    Post  IronsightSniper on Sun Nov 07, 2010 2:19 am

    GarryB wrote:
    It's written by an American.

    My point was that it really doesn't give use any useful information except that the Georgians are crapping themselves and want to be rearmed so they can have another go so I really don't see the point of posting it.

    I will never get the minutes it took to read it back.

    In comparison the other articles were interesting and useful and more on topic.


    So it wasn't propaganda after all.

    Great! russia

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    Re: General Questions Thread:

    Post  havok on Sun Nov 07, 2010 7:49 am

    Folks,

    Here is the proverbial straight dope on this 'plasma stealth' tale...

    http://www.science20.com/news_account/stealth_antenna_made_of_gas_impervious_to_jamming
    Plasma antennas behave much like solid metal antennas because electrons flow freely in the hot gas, just as they do in metal conductors.
    Plasma antenna technology is nothing new. It has been around for decades. But in order to understand how a plasma antenna works, and naturally in concept how 'plasma stealth' works, one must understand something more basic, more mundane...

    http://csep10.phys.utk.edu/astr161/lect/earth/atmosphere.html
    The structure of the ionosphere is strongly influenced by the charged particle wind from the Sun (solar wind), which is in turn governed by the level of Solar activity. One measure of the structure of the ionosphere is the free electron density, which is an indicator of the degree of ionization.
    The Earth's atmosphere is composed of layers of ionized gases and ionized gas is -- plasma. Depending on frequency, a layer may reflect EM waves or pass through. The result of this effect is atmospheric deflections of radio signals that can travels over the horizon...

    Above the stratosphere is the mesosphere and above that is the ionosphere (or thermosphere), where many atoms are ionized (have gained or lost electrons so they have a net electrical charge). The ionosphere is very thin, but it is where aurora take place, and is also responsible for absorbing the most energetic photons from the Sun, and for reflecting radio waves, thereby making long-distance radio communication possible.
    The layers that pass through EM waves could be construed as 'absorbers', as in radar absorbers, because what are radar signals but EM waves, nyet?

    A plasma antenna does exactly that -- absorb certain freqs. The container that holds the ionized gas does nothing else except what it is designed to do. Electronic countermeasure (ECM) tactics works because there is a conductor. But if there is no antenna then there is no conductor. Switch power off to the gas and there is no plasma antenna, hence the point of the article.

    So what 'plasma stealth' does, in concept anyway, is to array around a body a chain of plasma antenna that will absorb known radar freqs, just like physical absorbers do, except the plasma antenna has greater bandwidth. It is not about creating a free plasma cloud around the body that could be stripped away by the environment -- moving air. To make this concept works, these plasma antenna should be as close to the surface as possible lest the aircraft's skin reflects the impinging radar signals, thereby defeating the purpose of the plasma antennas. But just as the Earth's atmosphere layers reflects certain freqs and pass through, or absorb, certain freqs, so will these plasma antennas in this array. Another issue is the power requirement. Power can be switched off on the side that is not being impacted by seeking radar signals. But what about when the aircraft is in an electronic dense combat environment? The best solution is a hybrid of body shaping and plasma antennas at certain locations on the aircraft's body that is known to be highly radar reflective and this technique can be applied to existing 'non-stealth' aircrafts as well.

    The US have studied this method of radar reflectivity avoidance and found it inferior to body shaping. The technology is promising but as far as military aviation goes, it is still too much in the infancy stage to be effective in deployment.
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    Re: General Questions Thread:

    Post  GarryB on Sun Nov 07, 2010 9:27 am

    So it wasn't propaganda after all.

    It claims that Russia was planning Georgias attack on South Ossetia for months in advance... and that the pilots they captured were drunk...

    Clearly propaganda... of course we hear little else from Georgia it would be a bit of a shock if it actually told the truth for a change.

    The Earth's atmosphere is composed of layers of ionized gases and ionized gas is -- plasma. Depending on frequency, a layer may reflect EM waves or pass through. The result of this effect is atmospheric deflections of radio signals that can travels over the horizon...

    It is also the reason that during reentry ground control lose contact with spacecraft. A period or window where they just have to wait to see if they are OK entering the Earths atmosphere.

    The US have studied this method of radar reflectivity avoidance and found it inferior to body shaping. The technology is promising but as far as military aviation goes, it is still too much in the infancy stage to be effective in deployment.

    Just because the Americans couldn't make it work doesn't mean no one else could. The Americans were amazed by the SHKVAL rocket propelled torpedo when it was revealed to the west, but the first operational Soviet rocket propelled torpedo entered service in the 1950s.
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    Re: General Questions Thread:

    Post  IronsightSniper on Sun Nov 07, 2010 6:24 pm

    GarryB wrote:
    So it wasn't propaganda after all.

    It claims that Russia was planning Georgias attack on South Ossetia for months in advance... and that the pilots they captured were drunk...

    Clearly propaganda... of course we hear little else from Georgia it would be a bit of a shock if it actually told the truth for a change.



    And Russia claimed the opposite, again, claims.

    It actually said that NATO/Georgian Intel Officers said that Russian pilots were drunk, not just captured ones. So, it was a Secondary source, not absolute confirmable, but nothing for you to fret about.

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    Re: General Questions Thread:

    Post  havok on Sun Nov 07, 2010 7:13 pm

    GarryB wrote:
    The US have studied this method of radar reflectivity avoidance and found it inferior to body shaping. The technology is promising but as far as military aviation goes, it is still too much in the infancy stage to be effective in deployment.

    Just because the Americans couldn't make it work doesn't mean no one else could. The Americans were amazed by the SHKVAL rocket propelled torpedo when it was revealed to the west, but the first operational Soviet rocket propelled torpedo entered service in the 1950s.
    What make you think that the US was unable to 'make it work'? The fact that you guys are debating that there is a plasma cloud or 'field' enveloping the aircraft tells me that no one knows what he is talking about as far as plasma goes, how it is generated and how it actually works. Installing a rocket into a torpedo is not a propulsion conceptual problem but an engineering one, and to date, no one has yet to envelope a slow moving car in a plasma field in a 2D environment, let alone an aircraft moving at several hundreds km/h in a 3D environment. If there is going to be an engineering effort to exploit plasma's characteristics, it is best to use the plasma antenna array path rather than excitation of surrounding gases and lose the plasma field in flight. You are confused between failure to engineer versus a comparative study between concepts. The latter often involves successful engineering efforts to support all arguments but in the end, a committee determines that there are no advantages of one idea over the other.
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    Re: General Questions Thread:

    Post  nightcrawler on Sun Nov 07, 2010 10:31 pm

    ^^
    The fact that you guys are debating that there is a plasma cloud or 'field' enveloping the aircraft tells me that no one knows what he is talking about as far as plasma goes, how it is generated and how it actually works.
    I didn't know but I know now!! Thnx\

    @ http://www.scribd.com/full/41216219?access_key=key-7231ezjke4wyynglaa0

    page.67


    I juat read from here that it was something chemical in nature
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    Re: General Questions Thread:

    Post  GarryB on Mon Nov 08, 2010 12:37 am

    It actually said that NATO/Georgian Intel Officers said that Russian pilots were drunk, not just captured ones. So, it was a Secondary source, not absolute confirmable, but nothing for you to fret about.

    I don't really care what they have to say.



    Not interested in hearing Osama Bin Ladens point of view either.

    The fact that you guys are debating that there is a plasma cloud or 'field' enveloping the aircraft tells me that no one knows what he is talking about as far as plasma goes, how it is generated and how it actually works.

    Where did anyone suggest such a thing?
    I described what Plasma was and then described a perfectly good internal use for it inside the radar invisible radome to hide the radar antenna in a strike aircraft.

    I juat read from here that it was something chemical in nature

    A cheap desktop plasma ball works best with rare earth gases which not only makes making a plasma easier but makes it look pretty in different colours too.

    Regarding the photo above the mention of a plasma port is speculation... it looks like a simple access panel to me or it could be an antenna for some sort of avionics item.

    I would suggest that by the time they get beyond the early prototype aircraft and get to a full standard aircraft the front and rear edges will have dogtooth shapes to reduce RCS.
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    Re: General Questions Thread:

    Post  GarryB on Mon Nov 08, 2010 12:40 am

    The US have studied this method of radar reflectivity avoidance and found it inferior to body shaping. The technology is promising but as far as military aviation goes, it is still too much in the infancy stage to be effective in deployment.

    So would that make the combination of body shaping, materials, RAM coating AND plasma stealth for certain areas invalid?

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    Re: General Questions Thread:

    Post  havok on Tue Nov 09, 2010 1:20 am

    GarryB wrote:
    The fact that you guys are debating that there is a plasma cloud or 'field' enveloping the aircraft tells me that no one knows what he is talking about as far as plasma goes, how it is generated and how it actually works.

    Where did anyone suggest such a thing?
    I described what Plasma was and then described a perfectly good internal use for it inside the radar invisible radome to hide the radar antenna in a strike aircraft.
    Radomes are frequently opened for maintenance reasons. Not a good idea.

    GarryB wrote:
    The US have studied this method of radar reflectivity avoidance and found it inferior to body shaping. The technology is promising but as far as military aviation goes, it is still too much in the infancy stage to be effective in deployment.

    So would that make the combination of body shaping, materials, RAM coating AND plasma stealth for certain areas invalid?
    Look at it this way...You can have all body shaping, all RAM, or all 'plasma stealth'. Each 'all' will require considerable investments in research and development. Each will have strengths and weaknesses over the other options. If you cannot have 'all', and no one can, then we must, and usually do, resort to incorporation. We use the other options' strengths to make up for the other's weaknesses. A body's shaping that is inferior to another's shape can -- to some degrees -- compensate via RAM or 'plasma stealth'. But what if the plasma control system failed? The problem with incorporation is increased system complexity. Some are unavoidable, some are. The trick is how to achieve the 'are'.
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    Re: General Questions Thread:

    Post  GarryB on Tue Nov 09, 2010 2:38 am

    Radomes are frequently opened for maintenance reasons. Not a good idea.

    An AESA radar will not need maintainence for years, or so its proponents claim as modules fail the performance of the radar deteriorates but only by a very little amount performance wise so a cost saving is made by not bothering with maintanence and after a time period (measured in years) the faulty modules are replaced, rather than regular scheduled maintainence.
    Another factor is that these rare gases could be incorporated as part of a transpiration cooling system so that the radome is a sealed module that can be looked at when the scheduled replacement of modules is due.
    Or conversely the plasma gas could be contained in the hollow radom in front of the radar in a sealed unit that folds open to give access to the radar antenna.

    Look at it this way...You can have all body shaping, all RAM, or all 'plasma stealth'.

    Look at it this way, any technique at a measure results in an equivelent countermeasure... if yo put all your eggs in the shaping basket what happens with improved long wave AESA radars that are not effected by shape? Or electronic techniques that might render RAM ineffective? Or indeed methods that might make plasma stealth counter productive? Developing and using as many types of stealth as you can and applying them to their strengths and to counter the weaknesses of other methods simply makes sense.

    A good example is the western use of towed decoys. That is great because chaff slows down too fast and is rejected because it travels too slow. Another solution however is a 30mm or 23mm cannon shell where the shell has an external surface covered in corner reflectors so instead of having a tiny RCS its RCS is actually rather large and its aerodynamic shape and weight means it retains speed well, though its ballistic dive could be a problem unless the aircraft firing the shell dives too.
    Same problem, different solution... it is the superiority complex of the west that thinks its way is right.
    For IR guided missiles there is a flare shell and in the case of the Tu-22M3 the gun firing the shells can "deploy" 50 flares a second mixed with "chaff" shells. Simple to reload and maintain.

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    Re: General Questions Thread:

    Post  havok on Tue Nov 09, 2010 4:24 am

    GarryB wrote:
    Radomes are frequently opened for maintenance reasons. Not a good idea.

    An AESA radar will not need maintainence for years, or so its proponents claim as modules fail the performance of the radar deteriorates but only by a very little amount performance wise so a cost saving is made by not bothering with maintanence and after a time period (measured in years) the faulty modules are replaced, rather than regular scheduled maintainence.
    Another factor is that these rare gases could be incorporated as part of a transpiration cooling system so that the radome is a sealed module that can be looked at when the scheduled replacement of modules is due.
    Or conversely the plasma gas could be contained in the hollow radom in front of the radar in a sealed unit that folds open to give access to the radar antenna.
    Wrong...This is clearly spoken from a position of ignorance, particularly aviation maintenance. On any radar, peripheral components are usually the cause of maintenance issues before the antenna array itself.

    For example...

    http://www.chomerics.com/products/waveguide_gaskets.htm
    For effective EMI shielding and pressure sealing for choke, cover and contact flanges, Chomerics' waveguide gaskets ensure low insertion, low flange leakage, maximum heat transfer and minimum outgassing. Chomerics provides conductive elastomer waveguide gaskets to fit standard UG, CPR, and CMR flanges. They can also be custom designed to meet special requirements.

    http://events.nace.org/library/corrosion/cases/antenna.asp
    Condensed moisture from humid air ingress was responsible for inducing corrosion within the aft radar antenna from an RAAF P-3C Orion maritime surveillance aircraft. Porosity in the silver-plating of a flexible brass waveguide allowed moisture to penetrate to the brass substrate and cause dezincification. The moisture also induced corrosion of some of the AA-6061 aluminum alloy waveguides. An investigation determined that moisture ingress occurred at a waveguide flange, possibly from the failure of a seal.
    Waveguides are standard means of power transmission in radar systems and the seals between connections are quite often the cause of performance degradation. These and other peripherals must have periodic maintenance (PM) done to prevent the system from reaching that failure. The list is considerable. In peacetime, we have stricter maintenance requirements for obvious reason: war. In other words, should there be a time for war, we want to deploy with the best possible weapons systems and there is no other time to prepare for that potential than in peace. This is also applicable to flight controls, engines, environmental, structures, and electrical. In war, we do not have the luxury of preventative maintenance in all of those systems. In the USAF, we have gradations of aircraft status that we allow flight. Code One is when an aircraft is considered problems free. Code Two is when a system degradation does not impair overall aircraft flight capability. Code Three is when a problem is serious enough to cause loss of human life or asset destruction. In peacetime, we do not fly if there is a particular system degradation that will cause an aircraft to have Code Two status. But in war time, we will make that allowance. Code Three is obvious enough but most maintenance justifications from post flight debrief will be of Code Two category and sufficient to ground the aircraft from tomorrow's flight schedule.

    I know you are desperate to salvage your argument but you are defying known practices and decades of experiences worldwide. Russia is not immune from 'the real world'.

    GarryB wrote:
    Look at it this way...You can have all body shaping, all RAM, or all 'plasma stealth'.

    Look at it this way, any technique at a measure results in an equivelent countermeasure... if yo put all your eggs in the shaping basket what happens with improved long wave AESA radars that are not effected by shape?
    Wrong...ALL freqs are affected by target body shapes and dimensions. The issue is the degree of target resolutions.

    GarryB wrote:Or electronic techniques that might render RAM ineffective? Or indeed methods that might make plasma stealth counter productive?
    Do you even know basic radar detection principles to make these statements? I doubt it.

    GarryB wrote:Developing and using as many types of stealth as you can and applying them to their strengths and to counter the weaknesses of other methods simply makes sense.
    In principle...Yes. But in reality, complex systems have greater system failures, not just in frequency but also in severity. An aircraft that is capable of deploying complex countermeasures against radar detection but require financially excessive manhours and manpower to maintain is just as bad as having nothing at all.

    GarryB wrote:A good example is the western use of towed decoys. That is great because chaff slows down too fast and is rejected because it travels too slow. Another solution however is a 30mm or 23mm cannon shell where the shell has an external surface covered in corner reflectors so instead of having a tiny RCS its RCS is actually rather large and its aerodynamic shape and weight means it retains speed well, though its ballistic dive could be a problem unless the aircraft firing the shell dives too.
    Same problem, different solution... it is the superiority complex of the west that thinks its way is right.
    For IR guided missiles there is a flare shell and in the case of the Tu-22M3 the gun firing the shells can "deploy" 50 flares a second mixed with "chaff" shells. Simple to reload and maintain.
    You have a gross misunderstanding of chaff and how it works. If the radar view is overwhelmed with chaff, it does not matter the chaff bloom's velocity. The West cannot alter the laws of physics. It is too bad for the rest that we know how to exploit those laws better than others can.
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    Re: General Questions Thread:

    Post  GarryB on Tue Nov 09, 2010 11:29 am

    Wrong...This is clearly spoken from a position of ignorance, particularly aviation maintenance. On any radar, peripheral components are usually the cause of maintenance issues before the antenna array itself.

    So what? Why would you open the Radome if you were working on radar electronics? You open the Radome to expose the antenna... and as I said there is no reason why a seal pocket in the radome could not be filled with the required gasses.

    Regarding accessing the antenna:
    As a benchmark, typical conventional fighter radars have Mean Times Between Failure (MTBF) of around 60 to 300 hours - AESA radars push the MTBF into the 1,000 hours or better class. Rather than several repairs annually to the radar, the AESA will see the radar needing repair only once every several years of operation. If we assume an annual flying rate of around 200 hours, on average the AESA needs to be repaired once every five years! From a support costs perspective, this means much reduced cost of ownership for fighter fleet operators who transition to the technology.

    http://www.ausairpower.net/aesa-intro.html

    I know you are desperate to salvage your argument but you are defying known practices and decades of experiences worldwide. Russia is not immune from 'the real world'.

    I am glad you are not making this personal...

    Wrong...ALL freqs are affected by target body shapes and dimensions. The issue is the degree of target resolutions.

    In practical terms long wave radar waves are not redirected away from the emitter by shaping.

    Do you even know basic radar detection principles to make these statements? I doubt it.

    You are an expert on Russian development clearly because you know all about plasma stealth. Just like my great great great great great grandfather was an expert on flying because he knew people would never be able to fly from country to country in aeroplanes... if you move faster than 30 miles an hour... well you couldn't breath at that speed!

    An aircraft that is capable of deploying complex countermeasures against radar detection but require financially excessive manhours and manpower to maintain is just as bad as having nothing at all.

    Sounds like a good argument against the 2 billion dollar a piece B-2s...

    It is too bad for the rest that we know how to exploit those laws better than others can.

    Yes, the super west... truth, justice, and oil wasn't it?

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    Questions about Su-25Sm.

    Post  mandeb48 on Sun Dec 12, 2010 4:34 pm

    I'm trying to figure out which radio equip the Su-25Sm
    The only information I have comes from here: www.prima.nnov.ru
    Also: the Su-25Sm lost external pylons for the R60?

    Tanks
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    Re: General Questions Thread:

    Post  GarryB on Sun Dec 12, 2010 11:11 pm

    AFAIK the R-60 pylons are replaced with pylons compatible with R-73.

    Radio equipment I am not sure about.

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    Re: General Questions Thread:

    Post  mandeb48 on Mon Dec 13, 2010 12:37 am

    GarryB wrote:AFAIK the R-60 pylons are replaced with pylons compatible with R-73.
    Radio equipment I am not sure about.

    thanks for the reply
    I've only seen pictures of Su-25Sm with 8 pylons in the wings, not 10 as in the original Su-25
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    Re: General Questions Thread:

    Post  GarryB on Tue Dec 14, 2010 2:25 am

    Actually that is the first time I have noticed that all the photos of the SM are 8 pylon.

    Of course it could be because of the low probability of meeting an enemy aircraft, but I would think they would keep the wing position for jamming pods like those fitted on the Su-25TM in lieu of AAMs.
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    Re: General Questions Thread:

    Post  medo on Tue Dec 14, 2010 7:51 pm

    No one knows the true RCS of either the F-22 or the F-35. And again...This 'long wavelength' thing is propaganda. Effective only for the gullible.
    [quote]

    I don't know for F-22 or F-35, but according to USAF long wavelenght P-12 and P-18 see Stealth F-117 and B-2 in 1999 war in Serbia and that is why F-117 and B-2 always have escort of EA-6 jammers.
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    Re: General Questions Thread:

    Post  GarryB on Wed Dec 15, 2010 12:52 am

    And also why one of the first attack missions of Desert Storm was AH-64s sent in to take out some isolated radar stations.

    The issue with long wave radars is that they need to be rather large and are therefore easy to plot on a map and target early on.

    A bit like SAMs up until the 21st C where the missiles able to reach up high have been large expensive missile systems that can't be bought in enormous numbers and are hard to hide when fielded.
    A satellite recon photo shows these SAM sites and the long wave radars so you can either deal with them first, or bypass them and hit command and communications targets first to weaken the AD network before you have a go at radar and heavy SAM sites.
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    Re: General Questions Thread:

    Post  nightcrawler on Wed Feb 02, 2011 6:24 am

    While reading about R-73 missiles I came across its guidance system which states:

    All-aspect infrared homing; & not just infrared homing; so what does the all-aspect stand for??

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    Re: General Questions Thread:

    Post  Austin on Wed Feb 02, 2011 6:33 am

    nightcrawler wrote:All-aspect infrared homing; & not just infrared homing; so what does the all-aspect stand for??

    Imaging Infrared (IIR Seeker ) , the new Russian AAM like RVV-MD have all aspect seeker.

    http://eng.ktrv.ru/production_eng/323/503/566/

    The missile features all-aspect passive IR guidance (two-color IR seeker) with combined aerogasdynamic control, a fixed-thrust solid fuel motor, a laser proximity fuse (for RVV-MDL) or a radar proximity fuse (for RVV-MD). The warhead is of rod type.
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    Re: General Questions Thread:

    Post  GarryB on Thu Feb 03, 2011 6:42 am

    All-aspect infrared homing; & not just infrared homing; so what does the all-aspect stand for??

    Early IR seekers needed a very hot target to get a good lock so when you are going up against a fighter like an F-16 you had to be directly behind them looking right up their tailpipe to get a good lock. If you tried to lock on from the front your missile would not lock and if you launched it who knows where it would go.

    The R-73 like the later model R-60s and the Iglas have much more sensitive IR seekers that can detect a pattern of IR points on the surface of a target so instead of having to fire them from the rear aspect, you can fire them from any angle or aspect... which makes them an all aspect weapon.

    As shown with British use of the AIM-9L during the Falklands war even when you have an all aspect guided missile you greatly increase your chances of a kill if you fire it from close behind the target but if they had wanted to they could have fired at the target while the target was head on and getting closer to you.

    Obviously the seeker lock range of a head on target is much shorter than for a tail on target in a high power setting but obviously being able to lock on and fire without having to manouver to get on the enemy planes tail is a big of an advantage.

    The R-73 also uses a UV filter to distinguish the difference between flares that release lots of heat (IR) energy but they also generate UV light as well, whereas an aircraft gives off IR energy but not UV light.

    Imaging Infrared (IIR Seeker ) , the new Russian AAM like RVV-MD have all aspect seeker.

    Not exactly, an IIR seeker is an all aspect seeker, but the original R-73, and indeed the AIM-9L or M or R models that came after it are not IIR.

    The difference between an IR and IIR seeker is like the difference between a light detector and a camera CCD chip. A light detector... like an IR seeker will detect intense light/heat and its precise direction, but will not really know what it is seeing. With an old IR seeker if you flew in front of the sun the IR seeker was just as likely to fly at the new larger heat source and ignore your aircraft. A IR detector in an IR guided missile can be set to target points that were not particularly hot so flares and the sun will be ignored for example.
    An IIR seeker sees more than just points of heat and can generate an image of the target much like a thermal imager does and so when looking at an aircraft rather than seeing hot points of the engine exhaust and the corners of the leading edge of the wings where friction heats it up you get a view of an aircraft in the IR wavelength.

    Defence against all aspect IR missiles is a bundle of flares you hope will form a pattern the missile confuses for your aircraft.

    Defence against an IIR missile is DIRCMs or perhaps an anti missile missile.

    iS THIS REAL??
    or just a fantasy

    It is clearly a computer model, but the question is what is it a computer model of?

    It seems to me to be an attempt at a jet engine with a variable pitch turbine blade that goes from no pitch (ie no suction when the core spins) to high pitch (ie lots of suction when the core spins). Obviously it would be easier to make the materials warp in a computer animation than in real life however.
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    nightcrawler
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    Re: General Questions Thread:

    Post  nightcrawler on Thu Feb 03, 2011 11:40 am

    It is clearly a computer model, but the question is what is it a computer model of?

    It seems to me to be an attempt at a jet engine with a variable pitch turbine blade that goes from no pitch (ie no suction when the core spins) to high pitch (ie lots of suction when the core spins). Obviously it would be easier to make the materials warp in a computer animation than in real life however.

    Its hard for me to understand Russian; but google translation shows it as some sort off Radar blockers in the air-intakes; tuned either for more stealth or for more thrust I don't know yet!!
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    Re: General Questions Thread:

    Post  GarryB on Fri Feb 04, 2011 1:38 am

    Its hard for me to understand Russian; but google translation shows it as some sort off Radar blockers in the air-intakes; tuned either for more stealth or for more thrust I don't know yet!!

    Ahhh.

    So what it is, is an engine blocker that hides a direct view of the engine.

    In a straight tube intake it is like looking down a straw at the front engine fan, so radar energy that goes down that tube hits the engine fan and comes straight out with a fairly strong radar reflection.

    One solution to this is to curve the intake so that the radar energy can't go straight in and hit the fan and come straight out back to the antenna. It means that any energy that comes back to the antenna has bounced several times in and out off the walls of the intake. Now as the intake walls will be covered in RAM every time it bounces it loses a few percent of energy and if it bounces 3 times in and three times on the way out that means the signal is reduced 6 x the performance of your RAM at absorbing energy. The shape of the intake trunk will be designed to maximise the number of times the signal bounces off the radar absorbing walls of the intake including a screen at the front that makes a lot of the energy bounce off or back in again... the result is that any energy actually getting back out of the intake will likely be weaker than the energy coming off other parts of the aircraft.

    This design you posted could be something that sits in the air intake trunk that is left straight when stealth is not so important but when it is rolled up (note the cog at the rear that winds the straight screens into a helix) it forms a helix like screen that radar energy would bounce around hundreds of times before it exits at the engine fan blade face to be reflected back through the helix... I rather doubt any radar energy would make it back to the emitter at all.

    The thing is that if this thing can be made to spin it will suck air in and improve airflow for the engine, in fact some air could be made to bypass the engine and it could act like a large turbofan.
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    Re: General Questions Thread:

    Post  nightcrawler on Tue Feb 08, 2011 7:29 am

    plz someone explain this phenomenon I am unable for now!!


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