Sukhoi PAK FA

StealthFlanker

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The hard facts are that F-22A will never reach supporters expectations due to basic physics – that have nothing to do with program cost(s). – Posted 14-Jan 2014 @theboresight.blogspot.com
It kinda funny how people put some science sounding words together with a bunch of nonsense assumption then call it basic physic , here are some mistake in that link just to name a few :
1) the author comparing an SR-71 flying at mach 3 with an F-22 flying at mach 1.7 ??? what kind of stupid comparison is that???? the temperature will be extremely different


2) while what he said about aerodynamic heating is correct ( yes they exist ) what he talk about aircraft unable to hide is completely wrong , there are load of stuff that will absorb infrared radiation , cloud is an example
. Moreover , passive sensor such as Infrared sensor lack capabilities to measures range and velocity by themselves and have to rely on LRF to generate firing solution , LRF has very short range , for example the one on OLS-35 can reach merely 20 km

3) and then there is this nonsense :
Target RCS (Radar Cross Section) [below] is determined by 1) the power transmitted in the direction of the target. 2) The amount of power that impacts the target and is reflected back in the direction of the radar. 3) The amount of reflected power that is intercepted by the radar antenna. 4) The length of time in which the radar is pointed at the target.
Radar cross section is the measure of a target’s ability to reflect radar signals in the direction of the radar receiver. In others words, it is a measure of the ratio of backscatter power per steradian (unit solid angle) in the direction of the radar (from the target) to the power density that is intercepted by the target , it has nothing to do with the radar time on target, increasing dwell time ( related to pulse length ) will increase the power of the reflection but the trade of is the range resolution will be horrendously bad

Moreover ,while high PRF can also improve capability of radar to detect target with low RCS, for unambiguous range measurements, no more than one pulse should be received from the target for each pulse transmitted by the radar. So there is a limit to how high PRF you could go. And the maximum detection range performance value that you often see is already taken in velocity search ( maximum PRF possible ) , so no more range improvement here.
4) then this
The weapon then dives down (using kinetic energy) to kill the target. The target profile presented to the AIM-54 is - the top of the target - not head-on. The top (stealthy or otherwise) provides the largestpossible target: surface area, physical size, and RCS aspect. F-14D (Infrared+radar) targeting in this way, with Phoenix alone - would have presented an unacceptable DACT (Dissimilar Air Combat Training) hazard for the new USAF F-22 Raptor.

firstly , all BVR missiles use a ballistic arc and lead intercept to extend range , AIM-54 isnt the only one
secondly , even though missiles can climb to higher altitude , the angular seperation is really insignificant , especially at long range. Moreover , how can the F-14 get the firing solution in the first place ? AAS-42 doesnt have a LRF device , and good luck lock on the F-22 with the APG-71 really.

5)
F-22A 'Pitot' tube is clearly visible at the nose. The Raptor has one tube on either side. These air measurement devices are electrically heated to ~ 270 C (520 F) to keep them from icing at altitude. Indeed, they appear as two hot spots on the nose under FLIR
i find it ridiculous that the author cant understand that size is a big factor in detection

6)
The IRST might also use its own stored 'Atmospheric Propagation Model' to effectively “make an educated guess” as to target(s) relative range, aspect, and velocity – without the radar or laser rangefinder. In effect, the sensors own performance is characterized to construct a sensitivity model against known objects at known distances and velocities. Then during wartime when IRST sees something - it compares its own “known” internal Atmospheric Propagation Model - and the weapons system then extrapolates target range and bearing.
To create such model you will need to know the exact speed altitude of target , and the exact atmospheric condition of that day ,as soon as the target doesnt fly at a fixed speed , altitude and the attmospheric condition change alittle bit then the accuracy for your guesstimate go out of window

7)
John C. Mather, Senior Astrophysicist at the Goddard Space Flight Center, Mars Society, University of Maryland 31-July, 2009; during his remarks on Doppler (red/blue) shift detection resolution-granularity in discussing astrophysics of celestial objects: “…we are able to see the velocity of a star down to one (1) meter per second.”
Advanced Flanker IRST Doppler-shift sensitivity will not require the granularity of astrophysics because an F-22 Raptor traveling at Mach 1.1 will be moving at approximately 374 meters per second. By including air combat closure rates - this figure is even higher (!)
This would seem to fall well within, the definition of militarily useful sensitivity?
I dont think author understand the different between visual light , infrared light and common radio frequency used in radar .While they are all electromagnetic wave in principal , their frequency are extremely different , infrared radiation for example has much much higher frequency ( shorter wavelength ) compared to radio frequency , so the doppler effect on them are much harder to observed , you pretty much need astronomical speed to be able to see the effect . Moreover, the reason why doppler effect can be used by radar to determine aircraft speed is because the radar know exact frequency that it transmitted. On the otherhand , you cant know the exact frequency of the infrared radiation that was radiated from adversary aircraft,because this frequency will change along with aircraft speed , altitude , moitures , ambient temperature ..etc none of these are constant , and not to mention the fact that the change is extremely small , you can see how impractical it is to use red/blue shift on IRST , they dont just put LRF on thermal system for fun.

8)
Conceptually one can act on a - 'False-Positive' - even if stealth is 100% effective in the radio spectrum:

a) IRST picks something up.
b) Point your radar at it.
c) No (or strange) radar return? = stealth.
d) We don't have stealth.
e) Select R-27T-R-77 class IR weapon - 'Fox!’
So basically he want to launch a missiles with out getting firing solution ( no target altitude , no aspect angle , no velocity , no distance to target , no loft angle ) , yep , say good bye to lead intercept and ballistics arcs , and good luck hiting anything from BVR with that method.
 

Bahamut

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So basically he want to launch a missiles with out getting firing solution ( no target altitude , no aspect angle , no velocity , no distance to target , no loft angle ) , yep , say good bye to lead intercept and ballistics arcs , and good luck hiting anything from BVR with that method.
Sir many future planned missile have look on after launch capability,so they go in the general direction using data link find the target and then lock on .
It kinda funny how people put some science sounding words together with a bunch of nonsense assumption then call it basic physic , here are some mistake in that link just to name a few :
1) the author comparing an SR-71 flying at mach 3 with an F-22 flying at mach 1.7 ??? what kind of stupid comparison is that???? the temperature will be extremely different


2) while what he said about aerodynamic heating is correct ( yes they exist ) what he talk about aircraft unable to hide is completely wrong , there are load of stuff that will absorb infrared radiation , cloud is an example
. Moreover , passive sensor such as Infrared sensor lack capabilities to measures range and velocity by themselves and have to rely on LRF to generate firing solution , LRF has very short range , for example the one on OLS-35 can reach merely 20 km
QWIP allows cooler temperature to detect. It can be used in a bigger plane in IR equivalent of AWACS on a larger plane capable of detecting cooler temperature thank to increase cooling of semiconductor and more computer power to find stealth plane at very long range like 300 km .
 

StealthFlanker

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Sir many future planned missile have look on after launch capability,so they go in the general direction using data link find the target and then lock on .
lock on after launch isnot some new technology that only future missiles have , even the old Aim-120 , R-77 , Derby ( and practically all radar guided missiles) all have lock on after launch capability . But lock on after launch only allow missiles to be launched without needing their own seeker to lock on target first (aka range not affected by missiles sensor ) , it doesnt allow your missiles to be launched without a firing solution. Without information like distance , altitude , target aspect angle , altitude then you practically launching blind , no loft , no ballistic arcs

QWIP allows cooler temperature to detect. It can be used in a bigger plane in IR equivalent of AWACS on a larger plane capable of detecting cooler temperature thank to
what a load of nonsense , while QWIP is good solution for many applications, it need very long integration time required to have similar detection performance to InSb or HgCdTe sensors. This means they have to give either frame rate or sensitivity to achieve otherwise similar performance. This is why most high-end military applications don't use QWIP technology. As a matter of fact, there is only small part of the spectrum (around 9 microns ) that QWIP has a tiny bit better performance compared to HgCdTe sensor ,for the rest of the spectrum , it is far inferior

increase cooling of semiconductor and more computer power to find stealth plane at very long range like 300 km
.
at what speed ? what altitude ? what aspect ? what weather condition ?
 

Bahamut

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lock on after launch isnot some new technology that only future missiles have , even the old Aim-120 , R-77 , Derby ( and practically all radar guided missiles) all have lock on after launch capability . But lock on after launch only allow missiles to be launched without needing their own seeker to lock on target first (aka range not affected by missiles sensor ) , it doesnt allow your missiles to be launched without a firing solution. Without information like distance , altitude , target aspect angle , altitude then you practically launching blind , no loft , no ballistic arcs
It is relative new for IR guided missile in WVR, BVR ranges. The variable are send via data link and most importantly the radar is tracking not locked on the enemy plane making it the enemy less aware of attack.
what a load of nonsense , while QWIP is good solution for many applications, it need very long integration time required to have similar detection performance to InSb or HgCdTe sensors. This means they have to give either frame rate or sensitivity to achieve otherwise similar performance. This is why most high-end military applications don't use QWIP technology. As a matter of fact, there is only small part of the spectrum (around 9 microns ) that QWIP has a tiny bit better performance compared to HgCdTe sensor ,for the rest of the spectrum , it is far inferior
That ture that QWIP is better between 8-9 wavelength then HgCdTe but since it is longer frequency we can detect cooler object for long range monitoring. Most IRST contain QWIP for long range and HgCdTe for shorter range detection. Other technique like QDIP, STJ etc are also being explored special QDIP.
at what speed ? what altitude ? what aspect ? what weather condition ?
The altitude is around 40,000 feet for a clear sky and enemy plane close to speed of sound.
 

StealthFlanker

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It is relative new for IR guided missile in WVR, BVR ranges. The variable are send via data link and.
Doesn't matter, it doesn't solve the problem i stated earlier, you need firing solution for ballistic arcs and lead intercept, otherwise say goodbye to BVR attack

most importantly the radar is tracking not locked on the enemy plane making it the enemy less aware of attack..
Tracking would mean you can put target in a series of range and velocity bins, but in your example, you dont know either range or velocity, not even heading or altitude, that is merely detection at best, not tracking
That ture that QWIP is better between 8-9 wavelength then HgCdTe but since it is longer frequency we can detect cooler object for long range monitoring. .
QWIP can get better than HgCdTe systems at 9 microns but it use much higher integration times so not exactly suitable for military applications , moreover their performance from 10-12 microns is similar, while for the rest of the spectrum HgCdTe is significantly superior
Btw, black body radiation isn't limited to long wavelength only

Most IRST contain QWIP for long range and HgCdTe for shorter range detection.
That is absolutely nonsense, QWIP are completely different from HgCdTe, tell me what exact system even use both at the same time? and what make you think QWIP can even be remotely comparable to HgCdTe in term of detection range?
The altitude is around 40,000 feet for a clear sky and enemy plane close to speed of sound.
You ignore 2 most important factors which are aspect angle and weather conditions, and what exact system we are talking about here?, what exact stealth aircraft? their size and exhaust temperature are not the same, close to speed of sound but at what exact speed? thermal signature is very different between mach 0.8 and mach 0.95
 
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Bahamut

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Doesn't matter, it doesn't solve the problem i stated earlier, you need firing solution for ballistic arcs and lead intercept, otherwise say goodbye to BVR attack
I have said the data for initial guidance will be given by data link to give the genral area where enemy aircraft is present.
Tracking would mean you can put target in a series of range and velocity bins, but in your example, you dont know either range or velocity, not even heading or altitude, that is merely detection at best, not tracking
Why do you think trackng cannot find all that variables, is it due to hisheisenberg uncertainty principle? Tracking give genral area, speed, and even heading. Lock on give the exact one. All AWACS do tracking and the give speed, altitude, heading and other variables but the are not exact.
weather conditions,
What does clear sky means?
You ignore 2 most important factors which are aspect angle and weather conditions, and what exact system we are talking about here?, what exact stealth aircraft? their size and exhaust temperature are not the same, close to speed of sound but at what exact speed? thermal signature is very different between mach 0.8 and mach 0.95
Read about the SOFIA project between NASA and Germany which was used for space research. The same principle can be used for detect stealth plane. Such plane had capability to operate at the entire IR spectrum. As for the 300 km it from rear when heat flow is max.
higher integration times so not exactly suitable for military applications
QWIP is used to detect at long ranges so a time delay can be accepted
 

Chinmoy

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Cockpit
АК ФА / Т-50-4 борт №054 перед вылетом из Комсомольска-на-Амуре в Раменское, 15.01.2013 г. (фото – пресс-служба ОАО “Сухой”, http://ria.ru). PAK-FA / T-50-4 board №054 before departure from Komsomolsk-on-Amur in Ramenskoye, 15/1/2013 (photo – the press-service of JSC “Sukhoi”, http://ria.ru).

The T-50 has a glass cockpit with two 38 cm (15 in) main multi-functional LCD displays similar to the arrangement of the Su-35S. Positioned around the cockpit are three smaller control panel displays. The cockpit has a wide-angle (30° by 22°) head-up display (HUD), and Moscow-based Geofizika-NV provides a new NSTsI-V helmet-mounted sight and display for the ZSh-10 helmet.

Large wide-angle (30° by 22°) head-up display (HUD)
Система индикации на лобовое стекло Т-50 и моделирование изображения ИЛС на компьютерном симуляторе кабины Т-50 в КБ Сухого, г.Москва, 01.03.2010 г. (ТВ-кадры, http://rutube.ru). Display System on the windshield of T-50 and ILS simulation image on a computer simulator cockpit T-50 Sukhoi, Moscow, 01.03.2010 (TV footage, http://rutube.ru)
NSTsI-V helmet-mounted sight and display

Primary controls are the joystick and a pair of throttles.The aircraft uses a two-piece canopy, with the aft section sliding forward and locking into place. The canopy is treated with special coatings to increase the aircraft’s stealth.



The T-50 employs the NPP Zvezda K-36D-5 ejection seat and the SOZhE-50 life support system, which comprises the anti-g and oxygen generating system. The 30 kg (66 lb) oxygen generating system will provide the pilot with unlimited oxygen supply. The life support system will enable pilots to perform 9-g maneuvers for up to 30 seconds at a time, and the new VKK-17 partial pressure suit will allow safe ejection at altitudes of up to 23 km.

Ejection seat K-36D
Pilot dressed in a suit PPK-7 helmet IMS-10 with mask KM-36M on the seat F-36D-5 and next to the oxygen system KS-50 / Source: mycity-military.com
Scientific Manufacturing Company Zvezda announced the completion of the tests the state of new life-support systems designed for remote control of the 5th generation fighter T-50 PAK FA.

CEO and chief engineer of the company at the same time, Sergei S. Pozdniakow, at a press conference at the United Aircraft Corporation (OAK) announced the completion of the testing phase of the main elements of life support system remote control, designed for fighter Sukhoi T-50 PAK FA.



It includes:

Multifunctional protective helmet IMS-10; (ZSh-10)
oxygen mask KM-36M;
G-suit PPK-7;
pressure suit JCC-17; (VKK -17)
oxygen system KS-50;
ejection seat K-36D-5.

Helmet IMS-10 (ZSh-10) with mask KM-36M / Source: mycity-military.comPAK FA flight suit @paralay.net

These facilities helps to keep alive the pilot even in situations where at an altitude of 20,000 meters will decompress the cockpit of the aircraft. The new helmet is also 350 grams lighter than currently used in the Russian Air Force (VVS) @nowastrategia.org.pl
Tons of interesting reads mate. Thanks a lot :yo:. Just one question......... Hasn't Su-47 has been shelved as TD? Or is the project still alive??
 

Bahamut

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Tons of interesting reads mate. Thanks a lot :yo:. Just one question......... Hasn't Su-47 has been shelved as TD? Or is the project still alive??
Yes it is now shelved as a Technology demonstrator........................................
 

StealthFlanker

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I have said the data for initial guidance will be given by data link to give the genral area where enemy aircraft is present.
To send the missiles the information about where the aircraft is present through datalink , first you need to have those information , which you dont if you do as the author of that blog suggest

Why do you think trackng cannot find all that variables, is it due to hisheisenberg uncertainty principle? Tracking give genral area, speed, and even heading. Lock on give the exact one. All AWACS do tracking and the give speed, altitude, heading and other variables but the are not exact.
You misunderstood my point , i didnt said radar tracking cannot get information about range and velocity , i said the method proposed by the authors of the blog you referenced will not get you range , velocity , heading , or altitude of target , so you cannot generate a firing solution. Here is what he proposed
Conceptually one can act on a - 'False-Positive' - even if stealth is 100% effective in the radio spectrum:

a) IRST picks something up.
b) Point your radar at it.
c) No (or strange) radar return? = stealth.
d) We don't have stealth.
e) Select R-27T-R-77 class IR weapon - 'Fox!’
What does clear sky means?
clear sky only mean no cloud , but there are others factors such as humidity and ambient temperature that will significantly affect performance of thermal system.

Read about the SOFIA project between NASA and Germany which was used for space research. The same principle can be used for detect stealth plane. Such plane had capability to operate at the entire IR spectrum.
SOFIA does not use either QWIP or HgCdTe together , its MIR detector actually used Si(As) and Si(Sb) BIB array. Moreover, the aperture of it's thermal system is around 2.7 meters in diameters , you cannot put such thing on a fighter





As for the 300 km it from rear when heat flow is max.
So the detection range is 300 km when the aircraft at max wet thrust and tail aspect ? , great , now from head on aspect the range would be 1/3 of that , if the aircraft was flying at Mach 0.8 instead of Mach 1 and use flight idle instead of full afterburner then you can say good bye to another 50% of the detection range. Now how far do you think something like APG-77 or APG-81 can detect something of 747 size ?
QWIP is used to detect at long ranges so a time delay can be accepted
Not that simple, long integration time is acceptable for application such as astronomy because the stars will not go outside of your momentary FoV, moreover , for astronomy , you have all days and all nights to scan the whole sky , not the same case for Military application, you will end up looking too long at the direction where adversary isnt there , not to mention the fact that you cant track multiple target from different direction if your IRST has long intergration time.
 

Bahamut

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SOFIA does not use either QWIP or HgCdTe together , its MIR detector actually used Si(As) and Si(Sb) BIB array. Moreover, the aperture of it's thermal system is around 2.7 meters in diameters , you cannot put such thing on a fighter
Sir I suggest to use a same concept to detect planes .A big plane with a lot of power and cooling system so it is more sensitive to find hot spots .
first you need to have those information
Use it locate a stealth plane and pass the general co ordinates to missile via data link.Think of it as a AWACS that instead of radar use IR detection
SOFIA does not use either QWIP or HgCdTe together , its MIR detector actually used Si(As) and Si(Sb) BIB array. Moreover, the aperture of it's thermal system is around 2.7 meters in diameters , you cannot put such thing on a fighter
I know that ,I gave that as example for the IR AWACS idea.
You misunderstood my point , i didnt said radar tracking cannot get information about range and velocity , i said the method proposed by the authors of the blog you referenced will not get you range , velocity , heading , or altitude of target , so you cannot generate a firing solution. Here is what he proposed
He can use L or S band radar for tracking .Plus his IRST detected the plane
So the detection range is 300 km when the aircraft at max wet thrust and tail aspect ? , great , now from head on aspect the range would be 1/3 of that , if the aircraft was flying at Mach 0.8 instead of Mach 1 and use flight idle instead of full afterburner then you can say good bye to another 50% of the detection range. Now how far do you think something like APG-77 or APG-81 can detect something of 747 size ?
Why do you thing QWIP is use by military in limited amount even if HgCdTe even if the its give advantage is small.It is because the wavelength allows detector at longer ranges as it is more sensitive in 9-10 range.300 km is a rough estimate , no one knows the correct IR performance so the correct range .It is taken from performance of QWIP on fighter plane to detect fighter type target.
Not that simple, long integration time is acceptable for application such as astronomy because the stars will not go outside of your momentary FoV, moreover , for astronomy , you have all days and all nights to scan the whole sky , not the same case for Military application, you will end up looking too long at the direction where adversary isnt there , not to mention the fact that you cant track multiple target from different direction if your IRST has long intergration time.
Can you tell the time delay?
clear sky only mean no cloud , but there are others factors such as humidity and ambient temperature that will significantly affect performance of thermal system.
At 40,000 ft 99% humidity is not present ,you are nearly above clouds and they temp is nearly constant and outside temp is -40 to -57 C.
 

StealthFlanker

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Sir I suggest to use a same concept to detect planes .A big plane with a lot of power and cooling system so it is more sensitive to find hot spots .
And that big plane around the size of a 747 is also very easy to be found and shot down by stealth fighter too

Use it locate a stealth plane and pass the general co ordinates to missile via data link.Think of it as a AWACS that instead of radar use IR detection.
The problem with the method you proposed is that by using infrared as a main detector AWACs is significantly inferior to a normal radar-based AWACs
1) you cant determine target altitude
2) you cant determine target speed
3) you cant determine distance to target
4) you cant track hundred targets at a time like normal AWACs
basically you end up with something that perform much worse , then what the point ?

I know that ,I gave that as example for the IR AWACS idea.
The point of stealth is to detect and attack enemy before they can do the same to you ,an AWACs will be detected by stealth fighter ways before they can do the opposite

He can use L or S band radar for tracking .Plus his IRST detected the plane
What L band are we talking about here ? if you talk about the L band on the leading edge of PAK-FA and Su-35 then those are not radar , i already explained why http://defenceforumindia.com/forum/threads/f-35-joint-strike-fighter.9172/page-44#post-1205050
Why do you thing QWIP is use by military in limited amount even if HgCdTe even if the its give advantage is small.
Cant recall any IRST or FLIR system on fighter that actually use QWIP

It is because the wavelength allows detector at longer ranges as it is more sensitive in 9-10 range
HgCdTe can work within that range of infrared spectrum too , and even up to 12 microns

.300 km is a rough estimate , no one knows the correct IR performance so the correct range
an estimate would assume you have some numbers and made some calculation , pulling number out of thin air isnt estimate
.
It is taken from performance of QWIP on fighter plane to detect fighter type target.
Ah what exact fighter and what exact system we are talking about here ?
Can you tell the time delay?
about 10-100 times worse
At 40,000 ft 99% humidity is not present
,you are nearly above clouds and they temp is nearly constant and outside temp is -40 to -57 C.
The problem is that your adversary will not always cruise at 40000 ft , in fact combat ingress can be between 25-30k feet or even less depending on mission

Moreover , it is not the ambient temperature that is of concern but the background temperature that will be your concern , for example it is much harder to detect a target by IR sensor if you are flying at higher altitude because in that case the background would be the hot earth surface instead of cold sky
 

Bahamut

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HgCdTe can work within that range of infrared spectrum too , and even up to 12 microns
See you own graph the both are essential use less after 10 microns

And that big plane around the size of a 747 is also very easy to be found and shot down by stealth fighter too
There is something know as EW.Do you think that such a plane will be left alone ,it have its own EW plus escort plane to make sure it is not shot down
What L band are we talking about here ? if you talk about the L band on the leading edge of PAK-FA and Su-35 then those are not radar , i already explained why http://defenceforumindia.com/forum/threads/f-35-joint-strike-fighter.9172/page-44#post-1205050
Yes I know that but there are other land base L band radar to help.
Cant recall any IRST or FLIR system on fighter that actually use QWIP
Both Euro fighter and Rafale already have QWIP and Mig 35 and PAK FA will have QWIP
about 10-100 times worse
The problem with the method you proposed is that by using infrared as a main detector AWACs is significantly inferior to a normal radar-based AWACs
1) you cant determine target altitude
2) you cant determine target speed
3) you cant determine distance to target
4) you cant track hundred targets at a time like normal AWACs
basically you end up with something that perform much worse , then what the point ?
The point of stealth is to detect and attack enemy before they can do the same to you ,an AWACs will be detected by stealth fighter ways before they can do the opposite
It will still be unable to engage without becoming visible to the IR AWACS,the entire concept is to detect a stealth plane before he can engage
in fact combat ingress can be between 25-30k feet or even less depending on mission
Then they will genrate even more heat due higher air friction then say at 40,000
 

Bahamut

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about 10-100 times worse
The exact no ,from what I know the time delayis in microsecounds
The problem is that your adversary will not always cruise at 40000 ft , in fact combat ingress can be between 25-30k feet or even less depending on mission

Moreover , it is not the ambient temperature that is of concern but the background temperature that will be your concern , for example it is much harder to detect a target by IR sensor if you are flying at higher altitude because in that case the background would be the hot earth surface instead of cold sky
At such altitude the air friction will be higher and air frame will heat more .It can still be detected
 

StealthFlanker

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See you own graph the both are essential use less after 10 microns
they are not useless per say , they just have very low quantum efficiency at that range.Si(As) and Si(Sb) are superior in VLW

There is something know as EW.Do you think that such a plane will be left alone ,it have its own EW plus escort plane to make sure it is not shot down
Now we come back to the issue of EW efficiency and RCS



Yes I know that but there are other land base L band radar to help.
In which case why bothered with the IR AWACs ? what the point ?
Both Euro fighter and Rafale already have QWIP and Mig 35 and PAK FA will have QWIP
Neither OFS or Pirate use QWIP
Mig-35 also use OLS-35 if i remember correctly , and obviously not QWIP
No official information about PAK-FA at the moment but likely that it wont use QWIP either


It will still be unable to engage without becoming visible to the IR AWACS,the entire concept is to detect a stealth plane before he can engage
You know to look at long distance , for optical sensor you need to zoom right ? You wont see the whole FoV at the same time if you want long range performance
Then they will genrate even more heat due higher air friction then say at 40,000
But then there is alot more moisture to absorb the radiation , and if target was flying 25-30K feet , it is likely that it was flying at lower altitude , so you gonna have to find it within hot background.
The exact no ,from what I know the time delayis in microsecounds
exact time delay depending on what kind of target you want to look at , cooler , fainter target will require more times
 

Bahamut

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@StealthFlanker
I will try clear some doubts on IR AWACS
1.It will have capability to use the entire IR spectrum using multiple sensor
2.They will place in such a way that entire area is covered similar to DAS in F 35
exact time delay depending on what kind of target you want to look at , cooler , fainter target will require more times
Yes but it is still varies from micro to milli seconds that enough for military application
You know to look at long distance , for optical sensor you need to zoom right ? You wont see the whole FoV at the same time if you want long range performance
Sir the zoom is for the human,the computer does not require to zoom,it uses software and data analysis to bypass the zooming
What is the F 35 rcs for L band
Suppose F 35 go along with EG 18 to jam L band then the jamming will alert the adversary to a potential attack
There is one thing about stealth ,it does not make the aircraft invisible but rather difficult to detect. Stealth is more in planning your attack to avoid detection rather then design.A well trained and planned Rafale using the right tactics will penetrate a enemy zone undetected but a badly planned group of any stealth fighter might get caught in it
 

StealthFlanker

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Go and look at the wavelength both Pirate and OLS operate,QWIP is best suited for those wavlength
No
Pirate work in the range from 8-12 microns
Both OFS and OLS-35 work within 3-5 microns
but just because QWIP has better quantum efficiency at around 10 microns that doesn't mean it is used on Pirate or OFS for that matter. In fact, AAS-42, Legion pod and Tiger eye all work within 8-12 microns range, does that mean anyone of them used QWIP? No

Mig 35 has newer IRTS,OLS 35 is used by Su 35
So in what ways OLS-UEM is superior to OLS-35?, and can you point to any official source that said OLS-UEM use QWIP?
 
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StealthFlanker

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@StealthFlanker
I will try clear some doubts on IR AWACS
1.It will have capability to use the entire IR spectrum using multiple sensor
2.They will place in such a way that entire area is covered similar to DAS in F 35
So you want to cover the entire fuselage with several IRST sensors, each with aperture around 2.7 meters in diameter?, and DAS isnt a long range systems really

Yes but it is still varies from micro to milli seconds that enough for military application
No, the fact is, at the moment, no IRST or FLIR on fighter actually use QWIP, despite the fact that it isn't a new technology

Sir the zoom is for the human,the computer does not require to zoom,it uses software and data analysis to bypass the zooming
No, you are confusing between optical and digital zoom


What is the F 35 rcs for L band
The part that is in Mie region such as stabilator will have 4 times bigger RCS
 

Bahamut

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Pirate work in the range from 8-12 microns
Pirate is dual band at 3-5 micron and 8-10 micron
OLS is 3-5 micron and 8-12 micron
So in what ways OLS-UEM is superior to OLS-35?, and can you point to any official source that said OLS-UEM use QWIP?
NIIP has said that they have archived 2-3 times increase in detection range ,so it about 60-70 km for a subsonic aircraft from the front in clouded condition .Such figure can only be achieved with QWIP .
 

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