IIR has an image... like the image formed on a thermal imager.

An ordinary IR seeker sees hotspots but more like a radar display than a TV image.

Within a field of view a retreating fighter in full AB might appear as two dots or areas of heat with a third hotspot in the sky that is the sun. Old IR missiles chased the hottest biggest thing they could see, which usually meant the sun. To prevent the IR seekers chasing the sun they got filters and if they saw several hot things to not chase the hottest one, which led pilots to carry Flares of different intensities.

Late model IR guided missiles like R-73 and AIM-9M had much more sensitive seekers and saw an aircraft as a collection of hotspots and were never locked onto the hottest spot... they could lock onto the front of an aircraft at closer range. That is when flares had to be released in batches to form patterns in the sky to distract the missiles.

The IR seeker designers then went to two colour models that looked in IR and UV... because a front on lock on a warm spot on an aircraft wont be broken by flares because the front of fighters might have a signal in IR but no signal in UV,while the flares had a signal in both frequencies. The missile simply homed on to the locked on IR spot on the front of the aircraft and ignored anything giving off UV light (ie burning material).

DIRCM was the solution and IIR an attempt to defeat DIRCM by using filters that blocked polarised laser waves etc etc etc...

Russia’s Eastern Military District Gets S-400 Missiles

Russia’s Eastern Military District took delivery of a “regimental” set of S-400 Triumph air defense missile systems, the Defense Ministry said on Saturday.

Russia currently has four S-400 regiments - two in the Moscow region, one in the Baltic Fleet and one in the Eastern Military District.

By 2020, Russia is to have 28 S-400 regiments, each comprised of two battalions, mainly in maritime and border areas.

The S-400 Triumph long- to medium-range surface-to-air missile system can effectively engage any aerial target, including aircraft, unmanned aerial vehicles, and cruise and ballistic missiles at up to 400 kilometers and an altitude of up to 30 kilometers.

The Russian Defense Ministry has said there are no plans so far to export the S-400, which will be produced only for the Russian Armed Forces.

http://en.rian.ru/mlitary_news/20120609/173939294.html

Well thats 4 regiments up to now. 24 more to go by 2020.

So, that is 64 launchers to date?

TR1 wrote:So, that is 64 launchers to date?

It'd seem that way. 1 regiment = 2 battalions, and based on how they're deploying it appears that 1 battalion = 1 battery. Each deployed battery has 8 visible TELs, so there are at the very least 64 TELs, provided each battery has a full 8 and each regiment has a full two batteries. I can see a full regiment going to Kaliningrad, we already knew one battery was going to replace the last S-200 unit based there and a second battery could replace the handful of S-300PS batteries in the area. With the significantly increased engagement envelope (for combat aircraft, 250 vs. 90 km), one S-400 battery could easily replace the four or five S-300PS batteries in the area. The greater engagement range allows the system to hit targets, reacquire, and relaunch at new targets, meaning that they aren't really losing any defensive capability.

Why arnt Ramjet based propulsion popular with SAM as they were in 60's with SA-6 and Indian Akash now.

It offers propulsion all the way flight which is no coasting like solid fuel missile , low volume/weight because they need not carry oxidiser and offers decent speed with no drop down in speed in its entire flight.

Why arnt Russian or US missile designers not working on Ramjet propulsion , while AAM are now turning back to it.

I suspect ramjet propulsion was caught up in many cases by solid fuel rocket propulsion, which turned out to be less bulky and offered higher peak speeds and better acceleration... remember ramjets require rockets and ramjets.

When scramjet technology is mastered I suspect a shift back to scramjet technology, but there are penalties for ramjet designs including large internal areas for piping and airflow and combustion. In missiles like SA-6 and Kh-31 and Onyx the large empty space is taken up by the solid fuelled rocket used to accelerate the missile to a speed where the ramjet can be started and operated efficiently.

For air to air missiles having terminal manouvering performance is much more important than for many other types of missile because aerial targets can manouver in 3D space making interception more complicated.

For anti ship missiles solid fuel simply doesn't allow the range needed for a decent anti ship missile, so if you want supersonic performance your choice is dangerous liquid fuel rocket with a throttle like Kh-22M or Kh-32, or a ramjet/scramjet arrangement. The one high speed solid fuelled rocket anti ship missile is the Kalibre and only uses the solid rocket for the last phase of the engagement over a relatively short distance. This is possible because ships don't move very far very fast... a carrier operating at 45 knots can't turn on the spot and would be detectable from very long ranges so a long flight time is not a problem... unless it is hours...

There is still oxygen at high altitude for combustion, the problem for humans breathing is largely of the inefficiency of the human lung.

A Ramjet powered missile zipping along at mach 6 will be scooping up several kilometres of air per second... combustion shouldn't really be an issue... certainly to 30km altitude or more.

Oxygen concentrations would only become a problem at perhaps 50km or higher.

Of course with any jet engine there are problems with sharp turns where flameouts and stalls might become a problem.

The key advantage of Ramjets is the throttle where a high throttle setting will allow the weapon to climb and accelerate but once it gets to altitude the throttle setting can be reduced to extend range, while closer to the target area the throttle can be opened up again to increase terminal manouver capability.

The ability to chance the throttle setting on older missiles was less important but a modern missile with a digital navigation system with a range of flight profile options and fairly smart attack capabilities could utilise the flexibility of the ramjet propulsion and increase speed and flight range.


With a superior scramjet motor of course performance increases further so new speeds can be achieved... in fact a smart flight management system will become necessary to potentially prevent the missile accelerating during flight as it uses up fuel and gets lighter and faster to prevent it accelerating to too high a speed and being damaged from the heat of friction....

http://lenta.ru/news/2012/06/27/s400/

Sources in the military-industrial complex say China will be the first S-400 export customer. They will receive units after domestic needs have been met, likely no sooner than 2017.


Good stuff .

How may more S-400 regiment will become active until the end of present year. One more or?

One more is planned for September, I doubt anymore this year.

New S-400 Long-Range Missile Ready For Service – Official

A new long-range missile for Russia’s formidable S-400 air defense system will soon enter service, chief-of-staff of Russia’s Air and Missile Defense Command Maj. Gen. Andrei Demin said on Thursday.

“A long-range missile for S-400 has passed all trials and will soon be delivered to air defense units,” Demin told RIA Novosti without specifying the model.

According to experts, it could be the 40N6 variant, which has an active radar homing head and is capable of destroying airborne targets at ranges of up to 400 kilometers (250 miles).

Russia currently has four S-400 regiments - two in the Moscow region, one in the Baltic exclave of Kaliningrad, and one in the Eastern Military District.

By 2020, Russia is to have 28 S-400 regiments, each comprised of two battalions, mainly in maritime and border areas.

The S-400 Triumf long- to medium-range surface-to-air missile system can effectively engage any aerial target, including aircraft, unmanned aerial vehicles, and cruise and ballistic missiles at up to 400 kilometers and an altitude of up to 30 kilometers.

http://en.rian.ru/mlitary_news/20120628/174293966.html

So the danger rings round S-400 sites have just expanded greatly...