F22 vs. IRST and radar jammers

Anything goes, as long as it is about the Lockheed Martin F-22 Raptor
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sdkf251

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Unread post28 May 2015, 11:55

Just out of curiosity, isn't the R-27 HOJ missiles kind of a very "specialized" type of missile. Is this fielded as a regular load for Frontal aviation or just for special cases? Is there any Russian operational doctrine on when these missiles will be used?

I can understand if you want to take out an identified, regular scheduled flying airborne target like an AWACS, this seems to be the missile to use. But to shoot blindly at opposing aircraft seems kind of inviting the potential of the missile deciding to hit unintended targets along the way to the target. (especially long range targets)

Is there no mid-course guidance or terminal fusing for these types of missiles? ECM is not just about radar, but the whole operational electronic spectrum of the weapon system.
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hornetfinn

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Unread post28 May 2015, 14:04

eloise wrote:Delicated jammer is a really vague term . Aircraft ESM systems consist of receiving antenna , the central processor, and the transmitting antenna. The receive components on Rafale is SPECTRA, on F-35 is Asq-239. They both have central processor to detect, classify, generate jamming technique. however the transmitting part is a bit different, on Rafale the jamming signal is transmitting through the antenna spread through the aircraft airframe. On F-35 the jamming signal is transmitting through the radar T/R modules or towed decoy such as ALE-70. The advantage of SPECTRA is that jamming signal can be transmitted to any direction, the advantage of using APG-81 as a jammer is that jamming signal will be more powerful and focused due to better gain of radar. Also, the main reason that make stealth fighter's jamming more effective is their tiny RCS compared to legacy fighter
hope that clear up


F-35 uses (or can use) the AESA antenna also to receive signals. It obviously also has antennas all around the airframe to both receive and transmit signals for the ASQ-239. This gives the system also high gain (high sensitivity) receive antenna with ability to give very precise angle of arrival info about received signals. Of course it's also limited to FOV of the AESA antenna.

I have a feeling that F-35 ASQ-239 is capable of both receiving and transmitting jamming signals to all directions. Of course the frontal sector will have by far the most powerful jamming system with the APG-81 antenna.
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charlielima223

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Unread post28 May 2015, 14:29

hornetfinn wrote:Modern IRST systems are very good and can see targets long distances away. They can see very small heat differences and I'm sure that they can see F-22 or F-35 at fairly substantial distances away. However they are definitely affected by design features like nozzles, airframe and exhaust cooling and other IR reduction features. Any reduction in heat peaks is going to reduce detection and tracking range. It's impossible to tell how different heat signature F-22 or F-35 has compared to designs with minor IR reduction measures like almost any pre-5th gen fighter. IMO, it's likely that both have much lower IR signature but that's just a guess. Of course lighting up AB is going to make very bright heat source no matter what the aircraft in question is (although IR reduction measures would still have some effect).

IRST currently has some limitations like poor range resolution. Most IRSTs have quite poor magnification capabilities and thus can do target ID only at relatively short ranges. That also affects range resolution as range can be determined more accurately if there are more pixels available from the target. F-35 EOTS is an exception as it has similar magnification capabilities to targeting pods which have 5 to 20 times higher magnification capabilities to IRST systems.

One thing to notice is that most capable IR sensor cores (which set the performance of the IRST systems) are produced by USA, then folled by France, UK, Japan, Israel and Germany. Possibly include South Korea and maybe Taiwan in the list as well. After that there is huge gap before China and Russia in producing IR sensor cores. So the threat of IRST systems is rather low currently as potentially hostile countries don't have technology to produce really modern IRST systems. For example OLS-35 in Su-35 is still nowhere as good as AN/AAS-42 produced for F-14D over 20 years ago.


Two other good things to point out is that compared to a traditional radar found on fighter aircraft. IRSTs have a very narrow field of view and that they are more effected by weather conditions.
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mrbsct

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Unread post28 May 2015, 22:58

I know No Escape Zones(NEZ) is highly classified, but can anyone make precise calculations on these missiles like

AIM-120 B/C/D
Meteor
R77-1 Adder
R27 Alamo
R37 Arrow

And how does aircraft acceleration and kinematics effect the NEZ? Are missiles even effective after NEZ against a fast maneuvering opponent?
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Unread post29 May 2015, 00:04

hornetfinn wrote:Modern IRST systems are very good and can see targets long distances away. They can see very small heat differences and I'm sure that they can see F-22 or F-35 at fairly substantial distances away. However they are definitely affected by design features like nozzles, airframe and exhaust cooling and other IR reduction features. Any reduction in heat peaks is going to reduce detection and tracking range. It's impossible to tell how different heat signature F-22 or F-35 has compared to designs with minor IR reduction measures like almost any pre-5th gen fighter. IMO, it's likely that both have much lower IR signature but that's just a guess. Of course lighting up AB is going to make very bright heat source no matter what the aircraft in question is (although IR reduction measures would still have some effect).

IRST currently has some limitations like poor range resolution. Most IRSTs have quite poor magnification capabilities and thus can do target ID only at relatively short ranges. That also affects range resolution as range can be determined more accurately if there are more pixels available from the target. F-35 EOTS is an exception as it has similar magnification capabilities to targeting pods which have 5 to 20 times higher magnification capabilities to IRST systems.

One thing to notice is that most capable IR sensor cores (which set the performance of the IRST systems) are produced by USA, then folled by France, UK, Japan, Israel and Germany. Possibly include South Korea and maybe Taiwan in the list as well. After that there is huge gap before China and Russia in producing IR sensor cores. So the threat of IRST systems is rather low currently as potentially hostile countries don't have technology to produce really modern IRST systems. For example OLS-35 in Su-35 is still nowhere as good as AN/AAS-42 produced for F-14D over 20 years ago.

Every IRST system has advantages and disadvantages.

The IRST/ATFLIR effectiveness depends on a number of factors, such as scan volume, and if its radar slaved or not. The OLS in the earlier Flankers and Fulcrums doesn't use any Digital Image Processing, Even if the Chinese purchased a Canon camera and stuck it in a Flanker, without the Digital Image Processing, it wouldn't be as effective as the system on later F-16 aggressor jets.

Almost all the cases where a F-22 got smoked against F-5 aggressors were WVR with ATFLIR providing the lock. The radar was practically useless.

Also note that the F-35 has two different systems. EOTS and EODAS. The EOTS has a 40+ mile range against a fighter aircraft. The targeting pods on the F-16 are an earlier version. The EODAS doesn't have the same resolution at long range, but has 360 degree scan, and can point the EOTS at the target. The two systems are fused together to provide maximum situational awareness, even with low RCS targets and jammers.

My understanding is that frontline F-16 pilots don't train using their (ATFLIR) targeting pods for A/A engagements. The aggressor jets that fly against F-22s are trained to use them. Some reports say its an upgraded version of the AN/AAS-42 first used in the F-14D although my understanding is that there is multiple pods in use on the F-16 aggressor.
http://theaviationist.com/2014/02/21/re ... ed-nellis/
The F-5s were not using AN/AAS-42 pods, likely in part due to size and weight constraints
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eloise

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Unread post29 May 2015, 02:29

hornetfinn wrote: :x

F-35 uses (or can use) the AESA antenna also to receive signals.

My bad, i forgot to mention that
hornetfinn wrote: It obviously also has antennas all around the airframe to both receive and transmit signals for the ASQ-239. This gives the system also high gain (high sensitivity) receive antenna with ability to give very precise angle of arrival info about received signals. Of course it's also limited to FOV of the AESA antenna.

I have a feeling that F-35 ASQ-239 is capable of both receiving and transmitting jamming signals to all directions. Of course the frontal sector will have by far the most powerful jamming system with the APG-81 antenna.

From what i know ASQ-239 is a passive system some what similar to ALR-94 or Falcon Edge and all sources i can find only mentioned F-35 transmitting jamming signal through APG-81, ALE-70
sdkf251 wrote:Just out of curiosity, isn't the R-27 HOJ missiles kind of a very "specialized" type of missile. Is this fielded as a regular load for Frontal aviation or just for special cases? Is there any Russian operational doctrine on when these missiles will be used?

HOJ is the anti radiation mode of radar guide missiles like Aim-120, Meteor, R-77. When their radar doesn't work they can rely on passive sensor to home on radiated source
R-27EP on the other hand is a completely passive missile, which mean it only have anti radiation mode ( basically similar to AGM-88, KH-31)

sdkf251 wrote:I can understand if you want to take out an identified, regular scheduled flying airborne target like an AWACS, this seems to be the missile to use. But to shoot blindly at opposing aircraft seems kind of inviting the potential of the missile deciding to hit unintended targets along the way to the target. (especially long range targets)
.

R-27EP can be carried with R-27ET, R-27R to increase their effectiveness when enemy have powerful jamming or AWACS asset such as EA-18G, EF-111, E-2.. etc
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Unread post29 May 2015, 13:54

neurotech wrote:Every IRST system has advantages and disadvantages.

The IRST/ATFLIR effectiveness depends on a number of factors, such as scan volume, and if its radar slaved or not. The OLS in the earlier Flankers and Fulcrums doesn't use any Digital Image Processing, Even if the Chinese purchased a Canon camera and stuck it in a Flanker, without the Digital Image Processing, it wouldn't be as effective as the system on later F-16 aggressor jets.


This is all true. Modern IRST can be valuable tool as it provides very accurate video and images. Of course they have some drawbacks but no system alone is perfect.

All OLS systems in Flankers and Fulcrums are non-imaging systems. They can only detect sources of heat but can not create any images, just like many older heat-seeking missiles. Basically they will show the pilot a blip on the screen and nothing else. Digital image processing would not do any good for them as the detector is incapable of producing any real images. These types of detectors are also much less sensitive than modern imaging systems. Another drawback is the very low number of targets detected and tracked (like 1 to 4 vs hundreds in imaging systems).

neurotech wrote:Also note that the F-35 has two different systems. EOTS and EODAS. The EOTS has a 40+ mile range against a fighter aircraft. The targeting pods on the F-16 are an earlier version. The EODAS doesn't have the same resolution at long range, but has 360 degree scan, and can point the EOTS at the target. The two systems are fused together to provide maximum situational awareness, even with low RCS targets and jammers.


This is true and they complement each other extremely well. I think both of these systems along with sensor fusion will give some very interesting and unique capabilities for the F-35. We have seen ballistic missile/rocket detection/tracking, ground fire detection and aerial target detection/tracking. I think there are huge number of potential capabilities for the whole system, some yet not even imagined.
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mrbsct

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Unread post29 May 2015, 15:33

Is IRST capable of getting good missile lock on? IRST cannot determine range, and the range has to be determined by other sensors. I believe the PIRATE ISRT on the Tyhpoon can sense targets out to 90 km but can it use its Meteor to hit those targets?

For example if the IRST of the Tyhpoon sees a F22 or F35 at like around 80 km, and then ripple fires its entire Meteor load....do those missiles have a good chance of hitting?
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Unread post29 May 2015, 18:19

mrbsct wrote:Is IRST capable of getting good missile lock on? IRST cannot determine range, and the range has to be determined by other sensors.

yes, it can achieve missiles lock, most IRST have a LRF that can help it measures range ( but not velocity or aspects angle)
with sensor fuse, the fighter can use radar to measure range.

mrbsct wrote: I believe the PIRATE ISRT on the Tyhpoon can sense targets out to 90 km but can it use its Meteor to hit those targets?

For example if the IRST of the Tyhpoon sees a F22 or F35 at like around 80 km, and then ripple fires its entire Meteor load....do those missiles have a good chance of hitting?

90 km range is only if enemy fighter is at tail on aspects, maximum head on detection range of IRST again subsonic fighter is often around 30-40 km
And as explained before IRST and optical sensor have to zoom with very narrow FoV to achieve their maximum range,
for example :
OLS-27
A combined IRST/LR device for the Su-27, similar to the MiG-29's KOLS but more sophisticated, using a cooled, broader waveband, sensor. Tracking rate is over 25deg/sec. 50km range in pursuit engagement, 15km head-on. The laser rangefinder operates between 300-3000m for air targets, 300-5000m for ground targets.
Search limits are ±60deg azimuth, +60/-15° in elevation. Three different FOVs are used, 60° by 10°, 20° by 5°, and 3° by 3°. Detection range is up to 50km, whilst the laser ranger is effective from 300-3000m. Azimuth tracking is accurate to 5 secs, whilst range data is accurate to 3-10m. Targets are displayed on the same CRT display as the radar. Weighs 174kg.
OLS-27K for Su-33 featured new algorithms and better processor. It allegedly tracked targets in pursuit mode by their IR signature at 90 km during tests.

the maximum range are only achieved when 3° by 3° FoV are used.
So to answer your questions : yes these Meteor have good chances of hitting, but PIRATE detection range again fighter is more like 30-40 km rather than 80 km, and that is only in good weather conditions, if there is even a bit of cloud between Typhoon and F-35, F-22 then the IRST range shrink dramatically or even become useless

mrbsct wrote:The source wikipedia brought me to is the German Military website which said.


So can it find the F22 at 80 km? Maybye?

Firstly , according to the source :
The range of the system is between 50 and 80 kilometers, but could be up to 150 kilometers. The target identification can be carried out more than 40 kilometers. However, the weather conditions

So i would say in perfect weather condition the maximum range of PIRATE again fighter is 50 km head on , 80 km tail on , 150 km range is again things with very significant heat signature like Mig-25 , mig-31, SR-71 fly at mach 3 , 60K ft .The 150 km range may sound very significant , but it is for advertising purpose rather than real world use .As i stated before aas-42 have maximum range of 200 km , but it can detect something like an F-5 from only around 20 km .One can claim DAS have maximum 800 km range , but we all know the detection range again fighter is significantly shorter , like 20-25 km at best . . An example of maximum advertising range vs practical range of electric optical system :
Northrop AN/AXX-1 Television Camera System (TCS). TCS represents the TISEO/TCS family of stabilised TV telescopes, used by the USAF and USN on air defence and air superiority fighters. TCS provides sharp close-up images of hostile aircraft outside of visual range. Typical identification ranges quoted are. DC-10 at 85 miles, F-111 at 40 miles, C-130 at 35 miles and F-5 at 10 miles. TCS could be fitted to the F-18, though currently only the F-14A is equipped.

http://www.ausairpower.net/TE-EO-Systems.html
So you can see producer can easily claim AN/AXX-1 have range up too 85 miles or 140 km ,however in real world condition , again adversary such as F-5 , mig-21 , the range can shrink to less than 10 miles

According to Eurofighter pilot :
At a distance of about 50 km the Typhoon IRST (Infra-Red Search and Track) system could be capable to find even a stealthy plane “especially if it is large and hot, like the F-22″ as a Eurofighter pilot once said.

http://theaviationist.com/2013/02/21/ra ... yphoon-us/
so there you have it ,in head on position PIRATE can detect a supercruise F-22 from 50 km


mrbsct wrote:However I am not sure if it can track it effectively or find good identification ,range, position and velocity for its Meteor Salvo to be effective. How effective is the rangefinding, tracking system on the Tyhpoon?
Picard said that the Typhoon can still find the range by using by " PIRATE can carry out kinematic ranging (either through a weaving maneuver by a single fighter or datalinking several fighters together)." How true is this? This seems rather tedious
.
PIRATE doesnt have a LRF thus wont be able to measure range by conventional mean like other IRST .However in theory , PIRATE can measure range by using weaving( zig zag ) maneuver ( similar to what i mentioned earlier about how a RWR on fighter can passively measure range to another airborne target , same tactic , the only thing changed is the sensor ).
If you have several fighter , you can also datalink them and use triangulation to measure range , that is alot more simple , and if you triangulate for a long period of time , you will know the velocity of the enemy too.
Of course that is in theory , in reality , according to producer , PIRATE cant measure range


mrbsct wrote:The Tyhpoon website says:
Once a target has been tracked and identified PIRATE can be used to cue an appropriately equipped short range missile, i.e. a missile with a high off-boresight tracking capability such as ASRAAM. Additionally the data can be used to augment that of CAPTOR or off-board sensor information via the AIS. This should enable the Typhoon to overcome severe ECM environments and still engage its targets.

So at 50 km it can still use heat seekers like the ASRAAM without knowing the range,direction and velocity? However I doubt it would be effective because ASRAAM only travels Mach 3.

mrbsct they didnt say any where that PIRATE can be used to cue ASRAAM from 50 km distance , if target was at that distance it would make a lot more sense to use Meteor , since that missiles have much better kinematic , and it also have a data link .
The reason why they mentioned "short range missile, i.e. a missile with a high off-boresight tracking capability" is because , at shot range ( 15-20 km ) missiles dont have to fly in an arcs , they can fly a direct path and still reach target , range information wont be very necessary thus PIRATE can be used to cue missiles :D


mrbsct wrote:A duel between the Tyhpoon and the F22 in my estimates, the Tyhpoon will be instantly tracked by the F22 radar instantly around 260 km-200 km due to the RCS of the Typhoon being around 1m2 when weapons are loaded. The F22 is stealth, LPI and can use ALR-94 to make radar even more LPI so there is no way PraetorianDAS can jam or track it. While the Eurofighter outdated doppler radar can be easily tracked and jammed.

Eurofighter trance 3 will have CAPTOR-E MK2 , which is an AESA radar . Eurofighter can still jam F-22 radar by noise jamming , if it some how know F-22 is there ( by IRST or data link from ground VHF radar ). Of course F-22 can jam Eurofighter radar too , and it will be a lot more effective since F-22 have much smaller RCS , and more powerful radar
mrbsct wrote:The F22 plans the battle and gains a superior position such as above the Eurofighter out of the range of (PIRATE has only low azimuth when pointing up and F22 has higher flight ceiling)azimuth of the IRST. The Eurofighter has a superior missile the Meteor. No escape zones are around 25 km for the AIM-120B, and AIM-120C around 30 km(based on the report I found the that the improved AMRAAM in 2000 was supose to engage 9 g targets at 30 km, and Eurofighter pilots reporting they cannot escape 30 km F22 shots at Red Flag). AIM-120D is 50 percent increase range so around 45 km NEZ, 50 km if lucky and with the F22's superior kinetmatics to the F15's. The Meteor being three times the NEZ of AIM-120B is around 75 km NEZ.

NEZ is the distance where missiles will reach and over take target no matter what the aspect angle of it . It doesnt mean missiles will hit , it just mean the aircraft will have to defeat missiles by maneuver rather than turning and run away . NEZ depending alot on type of target , altitude ,missiles launching speed .
There is a very simple formula that can be used for estimating the performance of a missile. It goes like this :
Change in Velocity (Delta V) = 10 x Specific Impulse x LN (initial weight / final weight) m/s

This assumes that all the fuel is used to get the missile as fast as possible and
none is used to provide just enough thrust to sustain a given velocity.
In otherwords, it assumes an all-boost motor not a boost sustain motor.

For example, let'a take a look at the AIM-120A AMRAAM which we have some decent info on...

Launch weight = 335 lbs (Published stats)
Motor weight = 156 lbs (WPU-6/B HTPB rocket motor weight as per Raytheon)
Approximate specific impulse = 245 seconds (typical of HTPB solid motors)
Approximate fuel fraction of motor = 85% (typical of robust aluminum cased aerospace rocket motors)

OK... if 85% of the motor's mass is the fuel, we have about 132 lbs of fuel in the AMRAAM-A
-- roughly a 39.4% fuel fraction (sounds about right). So let's run the numbers...

Delta V = 10 x 245 x LN(335/(335-132)) = 1227 m/s

The formula predicts that the AMRAAM will go about 1227 m/s (~Mach 3.7) faster than it started.
If it is launched at say Mach 1.5 it'll be going Mach 5.2.
In reality the AMRAAM doesn't go that fast.
The reason is that not all the fuel is used to get it as fast as possible.
The AMRAAM's motor is a boost-sustain design.
It is probably grained to take the weapon to abut Mach 2.5~2.8 faster than it started at
(Mach 4+ in a typical Mach 1.5 release).
The rest of the fuel is shaped to burn much more slowly to keep it's velocity at
or near the achieved maximum out to a longer range before the motor burns out.


Well, for any given fuel fraction and specific impulse,
a designer can decide how fast he wants to go and how long he wants to stay at
or near the peak velocity achieved. For instance, if a missile carries 40% of its launch weight
as fuel and uses the typical a modern HTPB propellant motor, it can:-

(1) Spend 25% to get an approximate Mach 2.1 delta V and 15% on sustaining that speed for a relatively long while.
(2) Spend 30% to get an approximate Mach 2.7 delta V and 10% on sustaining that speed for a shorter while.
(3) Spend 40% to get an approximate Mach 3.8 delta V have no sustain burn time at all.

BTW, in reference to the above comment on deceleration... it doesn't really work that way.
If a missle starts at Mach 4 at burn out and decelerates 25% to Mach 3 after 10~15 seconds,
it WILL NOT decelerate to Mach 2 (another 33% from Mach 3) after 20~30 seconds.
This is impossible because aerodynamic drag (Fd = Cd x A x 0.5 x P x V^2) is a function of
the square of velocity.
As velocity decreases, drag force decreases exponentially in relation to it.
Hence, if the drag for at Mach 4 causes a 25% loss in velocity in 10~15 seconds,
there is no way a much lower drag force at Mach 3 will cause a 33% loss in velocity after
another 10~15 seconds.
What happens is that deceleration is non-linear;
you start off steep and the slope flattens out over time as velocity and hence drag drops.
It'll take a missile a heck of a lot longer to decelerate from Mach 4 to Mach 2 compared to
say Mach 2 to Mach 1 for instance.



Actually it also depends a heck of a lot on altitude (air density)...
Let's plug some numbers shall we?

Question: How much thrust is needed to sustain Mach 3.0 in an AAM like the AMRAAM?

Drag force (Newtons) = 0.5 x P x V^2 x Cd x A

P = Density of Air (kg/m^3) ; ~1.29 kg/m^3 @ sea level; ~0.232 kg/m^3 @ 12,000 m
V = Velocity (m/s) ; Mach 1 = 340 m/s @ sea level; ~295 m/s @ 12,000 m
Cd = Co-efficient of Drag ; ~ 0.6 to 0.95 for rockets depending mostly on finnage,
nose and tail profile
A = Sectional Area (m^2) ; ~ 0.025 m^2 for a 7" diameter missile.

For an AMRAAM like AAM going at high altitudes (40,000 ft)...

Drag Force @ Mach 3 = 0.5 x 0.232 x (295x3)^2 x 0.70 x 0.025 = 1590 Newtons = 357 lbs
Drag Force @ Mach 2 = 0.5 x 0.232 x (295x2)^2 x 0.70 x 0.025 = 707 Newtons = 159 lbs
Drag Force @ Mach 1 = 0.5 x 0.232 x 295^2 x 0.70 x 0.025 = 177 Newtons = 39.8 lbs

The same missile going Mach 3 at Sea Level...

Drag Force @ Mach 3 = 0.5 x 1.29 x (340x3)^2 x 0.70 x 0.025 = 11,744 Newtons = 2640 lbs
Drag Force @ Mach 2 = 0.5 x 1.29 x (340x2)^2 x 0.70 x 0.025 = 5,219 Newtons = 1173 lbs
Drag Force @ Mach 1 = 0.5 x 1.29 x 340^2 x 0.70 x 0.025 = 1,305 Newtons = 293 lbs

Assuming that there is no sustainer,
the deceleration experienced at Mach 3 by the 203 lbs (empty) missile is

Deceleration @ Mach 3 = -F / mass = -1590 / (203 x 0.454) = -17.3 m/s^2 = - Mach 0.059/sec @ 40,000 ft
Deceleration @ Mach 2 = -F / mass = -707 / (203 x 0.454) = -7.67 m/s^2 = - Mach 0.026/sec @ 40,000 ft
Deceleration @ Mach 1 = -F / mass = -177 / (203 x 0.454) = -1.92 m/s^2 = - Mach 0.0065/sec @ 40,000 ft

Deceleration @ Mach 3 = -F / mass = -11744 / (203 x 0.454) = -127 m/s^2 = - Mach 0.39/sec @ sea level
Deceleration @ Mach 2 = -F / mass = -5219 / (203 x 0.454) = -56.6 m/s^2 = - Mach 0.17/sec @ sea level
Deceleration @ Mach 1 = -F / mass = -1305 / (203 x 0.454) = -14.2 m/s^2 = - Mach 0.042/sec @ sea level

OK... enough of the math and the formulas... what does all these mean?
Well, it means that while coasting at Mach 3 an AAM is going to lose about less than 2% of
its velocity a second at high altitudes while it stands to lose about 13% of its velocity at
sea level! Huge difference isn't it?
Remember though that the rate of deceleration actually DECREASES as the
missile's velocity decreases.
It is easy to see that one can claim that a missile can burn out burn out its booster
and sustainer and be effective out to over 100 km at high altitudes or be useful only
against helos after 10km on the deck!

Also, we can make a pretty educated guess as to how much thrust the sustainer has to make.
An AMRAAM class missile with a 400 lbs sustain thrust will be able to stay
above Mach 3 at high altitudes and stay about Mach 1.2 at sea level.
An AMRAAM class missile carrying about 10% of its launch weight as sustainer
grained propellant will be able to keep this level of thrust lit for 20.5 seconds
in addition to whatever the boost time was using the 30% of its fuel to get a
roughly Mach 2.7 Delta V after launch.
A missile like this when fired at Mach 1.5 will reach Mach 4+ and keep
above Mach 3 for the duration of the sustainer at high altitudes.
It will also reach about Mach 2.5 and keep above about Mach 1.2 at sea level.
A motor grained for this thrust profile can have a 10 second boost at ~ 2460 lbs thrust and
a 20 second sustain burn at 400 lbs thrust -- this is a 5:1 boost sustain ratio.
This is also about right for thrust profiles of star grain vs
core burn solid propellant burn rate profiles.




Another rough rule of thumb:-

The time it takes for a missile to lose 25% of its velocity after burn out at supersonic speeds.

Never @ > 100,000 m (~300,000 ft) ; in space
~150 seconds @ 24,000 m (~80,000 ft)
~70 seconds @ 18,000 m (~ 60,000 ft)
~25 seconds @ 12,000 m (~ 40,000 ft)
~10 seconds @ 6,000 ft (~20,000 ft)
~5 seconds @ Sea Level

Remember, fractions over time are not additive.
In otherwords, if a missile loses about 25% of its velocity in 10 seconds,
in the 10 subsequent seconds (t =20s) the missile loses approximately another 25% of
the remaining 75% not a 100%. Total velocity loss is ~43.75% not 50%.

This is highly collated to the fall in air density.
Drag = 0.5 x P x V^2 x Cd x A.
Holding everything else constant Drag falls proportionally to density.
Drag also falls exponentially with Velocity which accounts for the loss in velocity
in the given time slices being about 25% instead of closer to 40%.
So based on the formula above you can estimated NEZ for yourself .


mrbsct wrote:In close range WVR, chances are lessened since Eurofighter has HMD and ASRAAM is better than AIM-9x

I dont think ASRAAM is better than AIM-9x , but sure in WVR , Eurofighter will have the upper hand because F-22 lack HMD
mrbsct wrote:If Eurofighter fought the F35, the F35's higher IR signature(lack of IR reducing nozzle and no supercruise)will put it at a disadvantage

I cannot find any reason why F-35 would have bigger IR signature than Eurofighter , or F-22 . No supercruise mean it fly slower thus have smaller skin friction => smaller heat signature . F-35 operate at lower altitude compared to F-22 , Eurofighter thus less contrast in heat signature with background and there are more moisture to absorb IR radiation . F-35 have IR reducing nozzle too ( it called LOAN nozzle ) , both F-22 and F-35 have a paint called Topcoat to reduce IR signature .
mrbsct wrote:plus it can carry only 4 AMRAAMs. Since its RCS is lower the CAPTOR can probably find it at 40-50 km unless the F35 decides to jam it.

CAPTOR (EF-2000 Tranch 1 and 2)

For RCS 0.0001 m2 class target: 12 km+
For RCS 0.001 m2 class target: 22 km+
For RCS 0.1 m2 class target: 70 km+
For RCS 1.0 m2 class target: 124 km+
For RCS 5.0 m2 class target: 185 km+
For RCS 10.0 m2 class target: 220 km+
CAPTOR-E will do better since it is an AESA radar , however , CAPTOR-E still smaller than APG-81 , APG-77 , and F-22/ F-35 were designed to penetrate S-300/400 defense , so i dont think there is any change for Eurofighter to detect them first by radar . Why wouldn't the F-35 pilot jam Eurofighter radar though ? :?
Btw According to recent interviewed F-35 have even lower RCS than F-22 .
mrbsct wrote:Also the F35 has bad kinematics so its NEZ is much lower than 45 km with the AIM-120D.

both Eurofighter and F-35 can carry Meteor .About NEZ , refer to the formula above
mrbsct wrote:If it came down to WVR, the Eurofighter has better manuerablity and the F35 can't carry the AIM-9x stealthily. The Eurofighter has a huge advantage over the F35 in WVR and BVR IMO. ]

F-35 have DAS and DIRCM , Eurofighter doesn't .And no Eurofighter doesnt have advantage over any stealth fighter in BVR
Last edited by eloise on 30 May 2015, 05:57, edited 4 times in total.
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eloise

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Unread post29 May 2015, 18:32

Picard and Wikipedia did claim PIRATE range of 100 km again subsonic fighter head on, however, there isn't any official source that support that assessment, so obviously that just one of many BS claim that he made
The producer of PIRATE however claim that it have maximum range of 145 km in perfect conditions , that may sound very high, however without knowing that type of target, altitude and aspect, that mean nothing, even Aas-42 have maximum range of 200 km

P/s : also, PIRATE actually lack LFR, unlike OFS, EOTS or OLS-35 :? , this actually a surprise for me, so Typhoon still have to rely on it's radar to lock target
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Unread post29 May 2015, 19:00

neurotech wrote:
Also note that the F-35 has two different systems. EOTS and EODAS. The EOTS has a 40+ mile range against a fighter aircraft. The targeting pods on the F-16 are an earlier version. The EODAS doesn't have the same resolution at long range, but has 360 degree scan, and can point the EOTS at the target. The two systems are fused together to provide maximum situational awareness, even with low RCS targets and jammers.

IMO
Since DAS range is alot shorter than EOTS, because it have much wider FoV compared to EOTS in maximum zoom , it is likely that EOTS will be cued by APG-81 and ASQ-239 rather than DAS. DAS may still cue EOTS at short range though
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Unread post29 May 2015, 21:06

The source wikipedia brought me to is the German Military website which said.

The range of the system is between 50 and 80 kilometers, but could be up to 150 kilometers. The target identification can be carried out more than 40 kilometers. However, the weather conditions

So can it find the F22 at 80 km? Maybye? However I am not sure if it can track it effectively or find good identification ,range, position and velocity for its Meteor Salvo to be effective. How effective is the rangefinding, tracking system on the Tyhpoon?

So the target identification is around 40-50 km depending on the wealthier conditions in my predictions. Picard said that the Typhoon can still find the range by using by " PIRATE can carry out kinematic ranging (either through a weaving maneuver by a single fighter or datalinking several fighters together)." How true is this? This seems rather tedious.

The Tyhpoon website says:
Once a target has been tracked and identified PIRATE can be used to cue an appropriately equipped short range missile, i.e. a missile with a high off-boresight tracking capability such as ASRAAM. Additionally the data can be used to augment that of CAPTOR or off-board sensor information via the AIS. This should enable the Typhoon to overcome severe ECM environments and still engage its targets.

So at 50 km it can still use heat seekers like the ASRAAM without knowing the range,direction and velocity? However I doubt it would be effective because ASRAAM only travels Mach 3.

A duel between the Tyhpoon and the F22 in my estimates, the Tyhpoon will be instantly tracked by the F22 radar instantly around 260 km-200 km due to the RCS of the Typhoon being around 1m2 when weapons are loaded. The F22 is stealth, LPI and can use ALR-94 to make radar even more LPI so there is no way PraetorianDAS can jam or track it. While the Eurofighter outdated doppler radar can be easily tracked and jammed.

The F22 plans the battle and gains a superior position such as above the Eurofighter out of the range of (PIRATE has only low azimuth when pointing up and F22 has higher flight ceiling)azimuth of the IRST. The Eurofighter has a superior missile the Meteor. No escape zones are around 25 km for the AIM-120B, and AIM-120C around 30 km(based on the report I found the that the improved AMRAAM in 2000 was supose to engage 9 g targets at 30 km, and Eurofighter pilots reporting they cannot escape 30 km F22 shots at Red Flag). AIM-120D is 50 percent increase range so around 45 km NEZ, 50 km if lucky and with the F22's superior kinetmatics to the F15's. The Meteor being three times the NEZ of AIM-120B is around 75 km NEZ.

So with the AIM-120D the F22 can beat the Eurofighter with superior positioning. But with the AIM-120C chances are lessened since IRST can find that range and its WVR. The F22 can fire at 50 km, to screw up the Typhoon's postioning to gain the upper hand at 30-40 km. In close range WVR, chances are lessened since Eurofighter has HMD and ASRAAM is better than AIM-9x.

If Eurofighter fought the F35, the F35's higher IR signature(lack of IR reducing nozzle and no supercruise)will put it at a disadvantage, plus it can carry only 4 AMRAAMs. Since its RCS is lower the CAPTOR can probably find it at 40-50 km unless the F35 decides to jam it. Also the F35 has bad kinematics so its NEZ is much lower than 45 km with the AIM-120D. If it came down to WVR, the Eurofighter has better manuerablity and the F35 can't carry the AIM-9x stealthily. The Eurofighter has a huge advantage over the F35 in WVR and BVR IMO.

Do you agree?
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Unread post29 May 2015, 22:16

mrbsct wrote:If Eurofighter fought the F35, the F35's higher IR signature(lack of IR reducing nozzle and no supercruise)will put it at a disadvantage, plus it can carry only 4 AMRAAMs.


The F-35 does have an IR reducing nozzle, it's just a different design that what was used in the F-22. And the F-35 may be capable of supercruise, depending on loadout. There's quite a bit that hasn't been publicly released about the plane, although it's publicly debated to no end.

There's another thread concerning the RCS of the F-35 with Sidewinders mounted on the far pylons. It's possible that the F-35 can carry 4 AMRAAMs and 2 Sidewinders without significant RCS penalty, so that would get an F-35 closer to the air-to-air loadout of a Raptor.
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Unread post30 May 2015, 00:33

Let's get off the F-35 discussion here. This topic isn't about the F-35, isn't the F-35 forum nor do I care about the F-35 in this forum. Future F-35 stuff mention here will be deleted.
I'm watching...
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Unread post30 May 2015, 06:20

Scorpion1alpha wrote:Let's get off the F-35 discussion here. This topic isn't about the F-35, isn't the F-35 forum nor do I care about the F-35 in this forum. Future F-35 stuff mention here will be deleted.

come on, why delete everything :( took me quite long to write that post :|
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