General Questions Thread:

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.

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.

^^

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

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.

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?

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'.

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.

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.

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?

Any Russian Equivalent to this

http://www.defencetalk.com/eye-in-the-sky-has-the-sniper-on-target-30080/

The last 28th Bomb Wing B-1B Lancer received the necessary modifications to operate the Sniper advanced targeting pod Oct. 18.

The advanced targeting pod acts as a long-range camera, which can pinpoint targets for precision strikes and close-air-support missions.

Any Russian Equivalent to this

Many. Platan is the simple system built in to the Su-34, but has no thermal imager, but OK for general use. The SAPSAN was supposed to be an equivelent of SNIPER but needs more funding and a lot of improvement yet. The Russian AF has chosen the French Damocles targeting pod and is licence producing it. There is the obsolete Mercury pod for the Su-25TM but it was poor. There is a pod called Solluks that is mentioned with the Su-34 but for all we know it could be the name of the Damocles in Russian service or a new Russian pod. Little is known about it in public info it was mentioned by Piotr Butowski (Spelling) in an article he wrote about the Su-34 some time ago.

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

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

Radio equipment I am not sure about.

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

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.

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.

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.

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??

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.

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.

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!!

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.

Name of middle missile??

I agree with psg, and would add that based on the size of the bomb compared with the R-77 I would say it was definitely a KAB-1500L-F.

The KAB-1500L-Pr is more compact, and the KAB-500 are much smaller.

Note the KAB-1500L-F is bomb that is guided (KAB) and has an overall weight of 1,500kgs (-1500), and is laser guided (L). The F means it is a HE Fragmentation warhead so the warhead has a lot of HE and a prefragmented shell to spray fragments around the place when it goes off.

The KAB-1500L-Pr is also guided and 1,500kgs and is also laser guided but the Pr means it is a penetrating round so the warhead still has HE but it also has a thick steel nose to penetrate into the target before a delayed fuse detonates the high explosive. Because it has a lot of steel in its nose it is much smaller... as you can imagine that 1 ton of HE takes up more space than 1 ton of steel... so the penetrating bomb weighing the same as a HE Frag bomb will look much slimmer and smaller because the steel penetrator is much denser.

This is interesting as it suggests the Mig-35 can now carry 1,500kg bombs which the Flanker can but the older model Fulcrums couldn't.

Such a bomb would be devastating to something like a ship... the smaller size of a penetrating munition like this further improves its ability to penetrate... for example if the target is in the basement of a tall building this is the sort of bomb you might want to use with the correct delay to hit it.

In the 1980s these sorts of weapons could only be carried by the Fencers. With the upgrades these weapons will be useable by Fencers, Backfires, Fullbacks, Fulcrums(35s), and Flankers(SM, 35s) and the big bombers... Blackjack and Bear.