Almaz S-300: China's "Offensive" Air Defense

man overbored said:

Aegis does not use dedicated data link channels for missile guidance. TVM uses a data link to feed steering commands to each missle from the fire control unit. Aegis is nothing like this. Each missile is given a waypoint prior to launch. Once launched the missile flies to this waypoint using it's inertial navigation system. The Aegis shooter does not need to feed it steering instructions for the missile to reach this waypoint.

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Look, if a missile is to get an optimal flight path during midphase flight, it needs a datalink. Anything from the AMRAAM to the late model Sparrows uses a datalink. If you rely on INS alone, the CEP at terminal range would have been much larger and prone to error.

Aegis may use link 16 to communicate a waypoint to a missile on another ship in the force however. Aegis was designed to allow non-Aegis ships to fire missiles that will be guided by the Aegis ship, thus the Aegis ship becomes more than just a guided missile platform, it is a battle management platform, and non-Aegis ships are in essence missile barges or outboard magazines for the Aegis ship. This is the reason a lot of Spruance class DD's were outfitted with VLS cells. They became magazines for the Aegis cruisers.

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This does not change that each missile also requires dedicated channels for illumination. You don't want all the missiles up in the air to be steered into one single illuminated target, don't you?

Aegis will then track both the targets coming in and the missiles outbound on their intercept tracks. If necessary, the AN/SPY-1 radar, not a data link but the actual radar transmitter, can communicate an updated waypoint to a missile.

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This is kind of dubious, since you would have problems when you have many missiles in the air. How can the radar transmitter serve all of them? If you are dedicating one radar transmitter per missile, the bottleneck would even be more severe. If one radar transmitter has to serve all the missiles in the air, you're back to square one, since each missile needs to know which and which is really meant for each particular missile, and that means channels.

This is nothing like the data links necessary to send steering commands to a missile like S-300 or Patriot PAC 1 and PAC 2 which use TVM. On those the missile's antenna reads the reflections of the ground radar off the target much as a semi-active radar does but then relays this information to the ground fire control unit, which in turn reads this data and sends each missile it's steering commands. Aegis is noting like this. Each missile flies autonomously to an inertial waypoint navigating from it's on-board INS.

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Datalink guided midphase > pure INS in terms of accuracy. This is not to mention datalink control provides for more optimum flight paths.

Only for the final fraction of a second does a fire control radar ( the SPG ) illuminate the target so the missile can complete it's intercept. On Aegis ships the illuminators can illuminate several targets at once, allowing several intercepts per illuminator.

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No, the illuminator actually juggles between targets. The illuminator used in the AEGIS vessels is surprisingly simple in design, like a parabolic reflector. That means it only emits one beam at a time. That is enough because all SARH illumination only works one beam and one missile at a time regardless of what type of array you use.

Since the illuminators are not used for the duration of each engagement but rapidly switched from target to target, several hundred engagements may be managed ( and that is the term ) at the same time since they won't all complete at exactly the same moment.

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Yes, that would be juggling between targets. Nonetheless you can do it with TVM too, just not as many.

Totoro said:

One interesting thing to note is that we can't see any targeting radars on 052c destroyer, which allegedly has hq9 missiles. There are two answers to that questions. A) its phased arrays work in dual bands, one for long range air surveillance, but can also quickly switch to narrow beams of higer precision wavelengths for targeting. That is something no country has implemented yet, though i've read next version of US Spy radars will have precisely that ability.

B) HQ9 guidance is active. Most probably active radar. While it raises the cost of each missile a bit, technologically it is perfectly doable and within reach for PLA. Taiwanese skybow 2 SAM is reported to have active guidance.

So, with active guidance and much newer electronics it seems safe to assume (sadly, we can only assume) HQ9 is superior to old s-300pmu. As far as later variants go... its too hard to tell. But then again, we can't even quantify the effecitveness of pmu as its never been used in combat, let alone its younger brothers.

BTW, one doesnt need defense coverage for the whole country. Having a SAM umbrella over empty fields or forests or small villages is a waste of resources. That being said, current number of around 20 s300 batteries plus handful (around 4?) hq9 batteries is still not enough. As long as hq2 needs to be used, i dont think the number will be enough.

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HQ-9 doesn't have an active seeker as far as is known. The best information is that it uses Track Via Missile as with Patriot PAC-1/2 or S-300.

AN/SPY-1 can definitely beam shape. Since sweeps occur basically at the speed of light, succeeding sweeps can use different beam shapes for specific purposes. There is even a scan that can pick up artillery shells over the beach to facilitate counter battery fire ( the Marines pressed for this one after the debacle in Lebanon ), which was mainly a software development of a scan built into the original Aegis system to sweep the horizon for sea skimming missiles.

Well, whatever current gen of spy radars does, next gen will do better. What i have read is that it will be able to provide continuous target illumination, so dedicated illumination radar dishes wont be needed anymore.

As for HQ9, no one knows for sure, but like i said, how do we explain its guidance on 052c destroyers? There is no visible targeting radar, whatsoever. To assume its main phased arrays are used for it is a bit too much, as it requires tech that isn't fully matured yet anywhere in the world.

As for AARGM, it is a new seeker on the old HARM airframe that can find a radar than has been secured, even a mobile radar, and destroy it. The old tactic of shutting off the radar to avoid the anti-radiation missile will be useless. HARM in fact can hit the last known position of a radar after it has been secured, AARGM expands this to find and nail moving radars or radars that were never turned on. By the way, the Serbs lost almost all of their search radars to HARM, their air defense system was completely disabled. Nato could fly all over Serbia with impunity and lost only two aircraft in that conflict. Credit HARM shooters and the EA-6B working together as a team. Today it would be the E/F/A-18G and AARGM.[/QUOTE]

If the fighter can pick up air-defense radar signal, (except for stealth), it means that the fighter is also picked-up by the radar. When the fighter launch the anti-radiation missiles, the air-defense unit will launch their SAM. It's still anybody's game. What do you think?

balance said:

As for AARGM, it is a new seeker on the old HARM airframe that can find a radar than has been secured, even a mobile radar, and destroy it. The old tactic of shutting off the radar to avoid the anti-radiation missile will be useless. HARM in fact can hit the last known position of a radar after it has been secured, AARGM expands this to find and nail moving radars or radars that were never turned on. By the way, the Serbs lost almost all of their search radars to HARM, their air defense system was completely disabled. Nato could fly all over Serbia with impunity and lost only two aircraft in that conflict. Credit HARM shooters and the EA-6B working together as a team. Today it would be the E/F/A-18G and AARGM.

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If the fighter can pick up air-defense radar signal, (except for stealth), it means that the fighter is also picked-up by the radar. When the fighter launch the anti-radiation missiles, the air-defense unit will launch their SAM. It's still anybody's game. What do you think?[/QUOTE]

No my friend, the amount of energy returning to a radar is always much lower than the energy of the signal striking the target. The target always has the advantage this way. It will be able, assuming the correct RWR is fitted, to detect an enemy radar long before the enemy radar detects the target.
Regarding Aegis, the SPG's can split their beam. Are you familiar with a rosette scan? The technique resembles this, a single dish can create multiple lobes, each lobe illuminating a different target. Since the actual time the SPG needs to illuminate the target is minimal, it is switched rapidly ( under a second ) from target to target, as long as their are targets available on the azimuth it is pointing. In a saturation missile attack this is assumed.
I repeat, Aegis does not use a data link. The inertial nav is more than sufficient to get the missle close enough to the target for semi active terminal homing to work. You have to keep in mind this radar scans at almost the speed of light, meaning each panel can complete literally thousands of task in a single second, as fast as the on board electronics can process data and operate the radar system. No data link is needed and the Aegis battle management system can guide several hundred missiles at one time this way. This is absolutely nothing like TVM.

No my friend, the amount of energy returning to a radar is always much lower than the energy of the signal striking the target. The target always has the advantage this way. It will be able, assuming the correct RWR is fitted, to detect an enemy radar long before the enemy radar detects the target. Quote

The Anti-radiation missile, once launched, will be detected by the radar. And the SAM will be launched, but instead of hitting the plane, it hits the missile. I don't think that the missile will be faster than the supersonic fighter itself.

The missile is much faster than any fighter. Phoenix for example was a mach 5 plus missile. HARM and AARGM are very large and fast missiles. As for the missile battery detecting and firing at the incoming anti-radiation missile, this so far has never happened. Such missions are accompanied by jamming aircraft such as a Rivet Joint or EA-6. The enemy radars are thoroughly disrupted during SEAD missions. It really isn't pretty what happens. If you look back in history, in the 1982 Bekka Valley campaign the Israeli's destroyed all but two Syrian radars in two days of combat over Lebanon. The Syrians did not even launch their aircraft the first day so certain were they of the capabilities of their systems ( after all, they had Soviet Army personnel operating these ). They were shocked how the Israeli's were able to demolish their radars. Once the radar was down, an F-16 soon appeared to bomb the actual missile batteries. The second day the Syrian Air Force took to the skies and quickly lost around 52 aircraft in a single day. Some of these had Soviet pilots, at least the recordings of them talking with their controllers was in good Russian. The Israeli method was clever. Send a small drone over the radar to get it's attention. This located the missile site. The Israeli's then ground launched Standard ARM missiles which homed in on the radiation of the SA-6's guidance radar destroying the radar site. Then the F-16 swooped in for the kill on the missiles themselves.
The US/Nato practice is to use specialized EW aircraft to jam the crap out of enemy radars so they do not see our incoming aircraft. Wild Weasel fighters can then launch anti-radiation missiles at the radar sites. If they shut off HARM remembers the last location of the emitter and homes on that, usually doing enough damage to disable the radar. AARGM will actually find radars even when turned off, and will take out moving targets as well. SEAD is one of the great strengths of our tactics. If you look at wars after 1973 there are few occasions were modern ground based air defenses have succeeded in deterring our air forces. Integrated ground based air defense systems are not very useful against a well equipped modern air force.

I repeat, Aegis does not use a data link. The inertial nav is more than sufficient to get the missle close enough to the target for semi active terminal homing to work. You have to keep in mind this radar scans at almost the speed of light, meaning each panel can complete literally thousands of task in a single second, as fast as the on board electronics can process data and operate the radar system. No data link is needed and the Aegis battle management system can guide several hundred missiles at one time this way. This is absolutely nothing like TVM.

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Only in close range. The farther the missile goes, the more you need a datalink which provides the midrange updates. Anytime you talk about midcourse updates, you need a datalink. A datalink does not necessarily mean a continuous data feed but you do need a digital radio channel that is open all times so it can receive the updates anytime in flight. Keep in mind that no matter how capable your radar is and what it is doing, as long as the missile is blind it does not mean anything. INS is just blind preset navigation, it does not compensate for evasive targets.

In fact, future plans for the Standard missile include hand offs to other platforms like AWACS or to other ships. That requires a datalink or a radio channel. So will if the Standard will use the AMRAAM seeker for future ARH guided variants.




US Navy Fact File Logo
Standard Missile

Description
Medium-long range shipboard surface-to-air missile.

Background
STANDARD Missile 2 (SM-2) is the world's premier surface-to-air air defense weapon. It is an integral part of the AEGIS Weapon System (AWS) aboard Ticonderoga-class cruisers and Arleigh Burke-class destroyers, and is launched from the MK 41 Vertical Launcher System (VLS) in US service. Its primary mission is fleet area air defense and ship self defense, but it also has demonstrated an extended area air defense projection capability and it has a secondary anti-surface ship mission. SM-2s use tail controls and a solid fuel rocket motor for propulsion and maneuverability and, in addition, extended range missiles have a booster with thrust vector controls. All are guided by inertial navigation and mid-course commands from AWS, and semi-active radar or an IR sensor for terminal homing.

SM-2 Blocks III, IIIA, IIIB, and IV are in service with the U.S. Navy; these and other variants of Standard Missile are also in service with thirteen allied navies.

SM-6, the Extended Range Active Missile, will provide a transformational enabler to the U.S. Navy to revolutionize Naval Warfare. Combining an AMRAAM active seeker onto the proven STANDARD Missile airframe, SM-6 will provide an extended range anti-air warfare capability both over sea and overland. This low-risk approach relying on Non-Developmental Items will support a FY 2010 IOC. With integrated fire control, SM-6 will provide the surface Navy with an increased battlespace against AAW threats over-the-horizon, taking full advantage of the kinematics available to STANDARD Missile.

If the fighter can pick up air-defense radar signal, (except for stealth), it means that the fighter is also picked-up by the radar. When the fighter launch the anti-radiation missiles, the air-defense unit will launch their SAM. It's still anybody's game. What do you think?

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What is anyone's game is when ground search radars and SAM radars start to use LPI techniques like frequency agile spread spectrum and pulse compression on the search radar, as well as very tight beam patterns with very little sidelobes or active sidelobe cancellation on the fire control radar. To explain the latter, SEAD aircraft depends on the target radar's sidelobs in order to detect the target. The HARM also depends on these sidelobs to gain a seek on.

Now the only time the radar is detected by the hunting aircraft is when a tight beam is already directly illuminating the aircraft. That's the good news---it can still be ultimately detected. The bad news is that a SAM is already on its way.

When it comes to the next generation of radars, the SEAD tactics have to seriously change.

man overbored said:

The missile is much faster than any fighter. Phoenix for example was a mach 5 plus missile. HARM and AARGM are very large and fast missiles. As for the missile battery detecting and firing at the incoming anti-radiation missile, this so far has never happened. Such missions are accompanied by jamming aircraft such as a Rivet Joint or EA-6. The enemy radars are thoroughly disrupted during SEAD missions. It really isn't pretty what happens. If you look back in history, in the 1982 Bekka Valley campaign the Israeli's destroyed all but two Syrian radars in two days of combat over Lebanon. The Syrians did not even launch their aircraft the first day so certain were they of the capabilities of their systems ( after all, they had Soviet Army personnel operating these ). They were shocked how the Israeli's were able to demolish their radars. Once the radar was down, an F-16 soon appeared to bomb the actual missile batteries. The second day the Syrian Air Force took to the skies and quickly lost around 52 aircraft in a single day. Some of these had Soviet pilots, at least the recordings of them talking with their controllers was in good Russian. The Israeli method was clever. Send a small drone over the radar to get it's attention. This located the missile site. The Israeli's then ground launched Standard ARM missiles which homed in on the radiation of the SA-6's guidance radar destroying the radar site. Then the F-16 swooped in for the kill on the missiles themselves.
The US/Nato practice is to use specialized EW aircraft to jam the crap out of enemy radars so they do not see our incoming aircraft. Wild Weasel fighters can then launch anti-radiation missiles at the radar sites. If they shut off HARM remembers the last location of the emitter and homes on that, usually doing enough damage to disable the radar. AARGM will actually find radars even when turned off, and will take out moving targets as well. SEAD is one of the great strengths of our tactics. If you look at wars after 1973 there are few occasions were modern ground based air defenses have succeeded in deterring our air forces. Integrated ground based air defense systems are not very useful against a well equipped modern air force.

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Good information. But if we take radars such as JY-11, YLC-8 (as found in sinodefence.com) which has anti-jamming capability, does it make difference?