Defense against Anti-Radiation Missiles

The Iraqi system was developed in collaboration between the Air Force and Air Defence Command after the 1991 defeat.

It was called the "Sarab" system "Mirage".

It was issued to Pechora units, and Iraqi officers from such units discussed it on the iraqi military forum. The system was designed to emulate the Pechora transmissions. It did not work with Kvadrat, OSA or ROLAND-II.

80 such systems were deployed by the ADC in the No-Fly-Zones. They were singularly successful against HARM and ALARM... eventually the US began using AGM-130s in the late 1990s, and an alternative "signal jammer" was used to drive it off-course in the terminal guidance stages.

Thank for the insight Sheytan, that is most interesting. There sure is a lot of interesting (and surprising) stuff waiting to be found out about what really happened between 1990-2003, at least concerning iraqi aviation/AD matters.

and most importantly since all systems mentioned above have Phased Array RADAR, they would be quite difficult to be picked off by ESM's , since they have low sidelobe (in order of -30 till -70 Db)

That's why ARMs are fitted with on-board satellite positioning systems to lock on the last stored location before the "blinking” .

It is 1,000 times more effective than HARM which in terms of hitting targets pretty mediocre... in the Kosovo conflict hundreds were fired with no effect.

Because that missile didn't has GPS at that time and of course the high mobility of Yugoslavian forces, AFAIK it did well in Iraq 2003 and US bombing of Libya 1986.

With modern Russian missiles even the ALARM would be ineffective except in enormous numbers to overwhelm the systems.

Garry your post was in 2011 and the missile was retired in 2013 ,nice prediction  UK retires ALARM missile

JohninMK wrote:I know its Easter but resurrecting a 7 year old post just to comment on it?  

Actually i was doing a research abour ARMs and i found that thread through Google .

Also ARMs still a threat and also get developed

The Soviet ARM, AS-11 required quite a sophisticated aircraft to operate it including a sensor pod to locate the targets before launch... the missile knew the physical location of the target before launch so if the source turned off it could still hit the location and with a 150kg blast warhead most of the time the antenna would be damaged and taken out even if the system turned off immediately after launch.

The new model is slimmer and designed to be carried internally on the PAK FA and also has IR sensors fitted... most large radars generate a lot of heat when operating so the sensor in the nose can detect and track the radar signal while the IR sensors detect its IR signature... if the radar turns off it can continue to home in on the fading IR signature and still get a direct hit... very clever.

HARM has only recently gotten GPS assistance, in the past if the radar turned off they missed. They were only used for suppression of enemy defences rather than the destruction of enemy air defences (ie SEAD rather than DEAD), so their purpose was not to destroy SAMs but to make them turn off so the aircraft could fly past safely... of course with modern TOR and Pantsir systems and various passive sensors to detect aircraft and cruise missiles making them turn their radars off was not good enough to make western aircraft safe any more so they had to change from SEAD to DEAD.

Most Russian SAMs can shoot down ARMs so they would not shut down their radars they would simply allocate a missile or two with dealing with any ARMs detected... and continue normal operations. Systems like S-350 and BUK-M3 use 12 missiles on each launcher to engage an increased number of aircraft and munitions.

I know its Easter but resurrecting a 7 year old post just to comment on it?

Well the alternative is to open a brand new thread on the same topic which I think personally would be the worse option.

BTW regarding the retirement of the ALARM...

It added: "UK armed forces have a range of capabilities that can be used to counter enemy air defence, including kinetic strikes via long-range cruise missiles, such as Tomahawk and Storm Shadow, and a multitude of highly effective precision air-to-ground weapons.

"Additionally, it is likely that we will work with our international partners on future major operations overseas and will therefore manage all of our capabilities as part of that coalition."

In other words we are going to use American missiles instead of British ones that are better... Blue Streak anyone?

ALARM was probably the most clever western ARM... it could be used in a range of modes including one mode where you fired it into a region you were about to fly through where it climbed up to very high altitude and then deployed a parachute and slowly descended while your aircraft or missiles flew through... any radars light up and it cuts the parachute and lights up a rocket motor and accelerates down to hit the radar... very clever... much more sophisticated than Shrike or HARM.

ALARM was probably the most clever western ARM... it could be used in a range of modes including one mode where you fired it into a region you were about to fly through where it climbed up to very high altitude and then deployed a parachute and slowly descended while your aircraft or missiles flew through... any radars light up and it cuts the parachute and lights up a rocket motor and accelerates down to hit the radar... very clever... much more sophisticated than Shrike or HARM.

Well not really a good idea. You only need fake radars to counter that. Put a an antenna that emits random signal every 10 km in your country and your are safe. Once you detect a HARM just turn off your radar and turn on one of the fake.

Having a missile that goes in the direction of the last detected position of the raar at mach 3 is better. At such speed it won't have time to move and will damage the radar. Even if not succeed the launching aircraft will come closer with smalker kh-25P.

GarryB wrote:The Soviet ARM, AS-11 required quite a sophisticated aircraft to operate it including a sensor pod to locate the targets before launch... the missile knew the physical location of the target before launch so if the source turned off it could still hit the location and with a 150kg blast warhead most of the time the antenna would be damaged and taken out even if the system turned off immediately after launch.

The new model is slimmer and designed to be carried internally on the PAK FA and also has IR sensors fitted... most large radars generate a lot of heat when operating so the sensor in the nose can detect and track the radar signal while the IR sensors detect its IR signature... if the radar turns off it can continue to home in on the fading IR signature and still get a direct hit... very clever.

HARM has only recently gotten GPS assistance, in the past if the radar turned off they missed. They were only used for suppression of enemy defences rather than the destruction of enemy air defences (ie SEAD rather than DEAD), so their purpose was not to destroy SAMs but to make them turn off so the aircraft could fly past safely... of course with modern TOR and Pantsir systems and various passive sensors to detect aircraft and cruise missiles making them turn their radars off was not good enough to make western aircraft safe any more so they had to change from SEAD to DEAD.

Most Russian SAMs can shoot down ARMs so they would not shut down their radars they would simply allocate a missile or two with dealing with any ARMs detected... and continue normal operations. Systems like S-350 and BUK-M3 use 12 missiles on each launcher to engage an increased number of aircraft and munitions.

In other words we are going to use American missiles instead of British ones that are better... Blue Streak anyone?

ALARM was probably the most clever western ARM... it could be used in a range of modes including one mode where you fired it into a region you were about to fly through where it climbed up to very high altitude and then deployed a parachute and slowly descended while your aircraft or missiles flew through... any radars light up and it cuts the parachute and lights up a rocket motor and accelerates down to hit the radar... very clever... much more sophisticated than Shrike or HARM.

You seems to forgot that actually Harm has been superseded by the AGM-88E AARGM, jointly developed by US and Italy, that feature an active millimetric wave radar in addition to the passive sensor, in order to counter the tactic of turning off the radar.

A costly solution surely,but the only one that could not be easily circumvented.

Russian new kh-58 has an IR imager to found the radar if it turns off.

A costly solution surely,but the only one that could not be easily circumvented.

Dummy radars will have the same radar signature so it is not 100% perfect.

Isos wrote:

A costly solution surely,but the only one that could not be easily circumvented.

Dummy radars will have the same radar signature so it is not 100% perfect.

I believe the standard solution is that every Russian SAM since the 1990s can pretty much shoot down ARMs... from BUK and S-300 right through TOR and Pantsir etc etc...

Pine doesn't even have a radar...

Well not really a good idea. You only need fake radars to counter that. Put a an antenna that emits random signal every 10 km in your country and your are safe. Once you detect a HARM just turn off your radar and turn on one of the fake.

Having a missile that goes in the direction of the last detected position of the raar at mach 3 is better. At such speed it won't have time to move and will damage the radar. Even if not succeed the launching aircraft will come closer with smalker kh-25P.

With a fully IADS what you could do is turn on radars for 30 seconds and then turn them off and listen with all the other radars... 30 seconds is not long enough for a wild weasel aircraft to lock you and launch a missile and get a kill nor for the high flying ALARM on its parachute to complete a kill before that radar goes off and another turns on... meaning your ARMs will be scrambling all over the place chasing its own tail... obviously you could coordinate it in your air defence system so you could detect any incoming missiles or aircraft but could also detect any ARMs in the air as well.

For every measure there are counter measures and counter counter measures...

Isos wrote:

A costly solution surely,but the only one that could not be easily circumvented.

Dummy radars will have the same radar signature so it is not 100% perfect.

Nobody have ever pretended that this or any other weapon have to be perfect, just capable to operate with more effectiveness.

In this AARGM is definitively a big step ahead to its predecessor, like new Kh-58 in comparison to the older model.

Both systems add a secondary targeting system to the main one, so is to be expected that they would retain a good grade of efficiency also against multiple dummy emissions tactic: in the end probably  kh-58 would turn to be more cost effective and AARGM more sophisticated but without any relevant advantage over the other solution anyway.

Said so , i expect both of them to have a very difficult task in facing the most modern AD systemsi.e. sporting missiles with mid course guidance and active radar terminal homing, as they were tough to deal with enemy targeting radars illuminating them along all the interception course and not instead with long range search ones just sending some mid range course correction signals to incoming missiles once in a while.

The top attack ALARM was actually created before GPS started widely to be used in such systems .

Since most of the radars became able to locate the air objects with high accuracy, the emission level of the horizontal sidelobes and backlobes have lowered, in comparison to high emission level of the vertical sidelobes.Regardless of the direction of the mainlobe emission of the radar, the ALARM passive anti-radiation homing receiver is able to track continuously the fluctuating microwave emission leaking upward from the radar’s antenna.

Isos wrote:Russian new kh-58 has an IR imager to found the radar if it turns off.

This is the way to go....
If enemy detects that you have fired ARM missile - he does not need to shoot SAMs against it. All it takes is to turn of the radar and count the time ARM missiles will fall from the sky blinbly - that is ofcourse only when there is no immediate threat from other air assets.
Having dual mode seeker easily defeats this tactic.

The original Kh-58 missile was more than just a stupid Shrike or HARM missile that homed in on a signal, it actually used onboard hardware of the aircraft that launched it to triangulate the actual physical location of the target radar before launch so even if it turned off the missile would continue to the place where the antenna was located to try to destroy it anyway.

The Kh-58 has a 150kg HE warhead for blowing down and destroying large radar antenna, so even a near miss would be offensive.

ALARM was also quite smart and determined the location of the target it was engaging.... but Shrike and HARM were intended to allow strike aircraft to slip through defences... if the enemy turned their radar off often that was good enough.

For a SEAD aircraft whose job it was to defeat enemy air defence or at least suppress them, then they needed something better.

Interestingly the IR sensor is effective because large radar antenna stay hot for long periods after being turned off making them an easy target for a missile with IR and radar homing guidance.

GarryB wrote:The original Kh-58 missile was more than just a stupid Shrike or HARM missile that homed in on a signal, it actually used onboard hardware of the aircraft that launched it to triangulate the actual physical location of the target radar before launch so even if it turned off the missile would continue to the place where the antenna was located to try to destroy it anyway.

I would suspect this to be not before but after the launch. Unless the KH-58 and onboard sensors would be ultra sensitive to the vertical plain angle of the signal received. Which i highly doubt. But it could launch and maintain a link with parent aircraft and track its distance from the airaft and angle, coount in the angle signal is detected fro aircraft and it could narrow down the location of the source signal. Simple pythagorean theorem... but it was smart approach in any case.

The difference was that Shrike and HARM could be carried by most western aircraft including bombers.

Kh-58 could only be carried by a select few Soviet aircraft with decent self defence ESM suites, and these ESM suites were used to determine the physical location of the target radars before they launched the missile... the missile had inertial navigation so they would home in on the radar emissions until either impact with the target or the radar turned off and would then use inertial navigation to impact.

The flew at mach 4.5 so the time to shut down the radar was pretty short anyway and the CEP was not very big over such a short flight time.

The Missile also received information from the launch aircraft and actually required an electronics communications pod so the aircraft could continue to communicate with the anti radiation missile after launch.

Later aircraft no longer use the electronics pod when carrying the ARM.

They also had the AS-11 and AS-12 anti radiation missiles based on the Kh-25 missiles with different seekers for different radar types. They were later upgraded with a single broad band seeker that allowed them to engage all types of HATO radars.