Subjects in the Focus IRIS-T SL Guided Missile

Ground-Based Air Defence (by Ulrich Rapreger a reprint of the article published in the April 2012 issue of Europäische Sicherheit & Technik with the author´s permission)

Air threats are posed by rockets, unmanned aerial vehicles, aircraft, helicopters, cruise missiles and grenades endangering population centers and critical infrastructure, such as dams and nuclear plants, but facilities and objects as well, for instance military camps of international forces in war and crisis zones. Ground-based air defence units contribute to safeguarding airspace as well as protecting the population and soldiers in action.  

Development

Diehl Defence was contracted for development of a modern guided missile with a launcher vehicle for ground-based air defence by the German Federal Agency for Defence and Procurement in 2007. The IRIS-T SL (Surface Launched) covers a broad target spectrum encompassing very short distances as well as medium-ranges. Based on this missile and in cooperation with leading sensor manufacturers, Diehl Defence is offering an entire , interoperable and adaptable air defence system with unique performance characteristics. Particularly the comprehensive target range, 360° protection against threats from shortest and medium-range distances as well as the unrestricted capability of engaging several targets and the high degree of automatization set new standards in future ground-based air defence. The mobile system permits mission-related area and point target protection. This pertains both to the protection of critical infrastructure or events and to homeland defence or international missions.

Weapon System Components

The IRIS-T SLM air defence system includes a sensor, an effector and a fire control system. All components are autonomous allowing missile-related combination. Moreover, they are highly mobile and air-transportable in C-130 class aircraft. All system components permit stationary employment integrated on a standardized 20 foot ISO container frame independent of the launcher vehicle.

Sensor

The IRIS-T SLM system utilizes the latest-generation 3D-multi-function radars as the main sensor. The radar, offering 360° coverage, is employed for air-monitoring and provision of target data enabling high update rates as well as different modes of seeker and target tracking. The system can be complemented with electro-optical sensors. They are designed for optical identification of targets in operations under the threshold of combat. Moreover, they can be employed for initiating engagement under combat requirements without radar-related radiation.   

Effector

The IRIS-T SL surface-to-air missile is the upgraded version of the IRIS-T missile employed as standard armament of modern combat aircraft in numerous European countries and internationally. The upgrade encompasses an enhanced rocket motor, a data link as well as an autonomous GPS/INS navigation system. The guided missile is delivered to the customer in light-weight, fibre glass-fortified, maintenance-free storage-, transport- and launch canisters. Within ten minutes, the launcher´s eight missiles can be reloaded by means of a revolving, vehicle-mounted crane. The pre-fragmented warhead as well as the IRIS-T SL´s rocket motor are insensitive. This rules out detonation by fire, lightning, shelling or improper handling (damage through impact) enabling employment in urban terrain.

In its terminal flight phase, the missile´s high-precision passive infrared seeker in conjunction with its outstanding resistance against active and passive countermeasures provide optimum target accuracy. The high-resolution seeker combined with advanced image-processing enables precise target analysis and a high image update rate capable of detecting aerial objects with low heat emission. The seeker not only registers minimum differences in temperature resulting from aero-dynamic friction. It also recognizes the target´s contours allowing selection of the optimum impact point in the target.

Target Spectrum

The weapon system can be employed against the entire spectrum of aircraft including rotary aircraft. Furthermore it is capable of effective engagement of cruise missiles, drones, U(C)AV, air-to-surface missiles (ASM), anti-radar rockets (ARM), anti-ship missiles, large calibre rockets and precision bombs.

Launcher Vehicle

Eight missiles are deployed on a remote-controlled and unmanned vehicle launcher. Ten minutes after entering the firing position it is fully operative. All eight guided missiles can be fired in a rapid sequence. Different targets in various directions can be engaged at a distance of up to 40 kilometers and an altitude of up to 20 kilometers. The missile´s high agility is complemented by minimum reaction times as well as the entire system´s operational effectiveness resulting in an “inner death zone” of less than one kilometer.

The launcher vehicle can be deployed up to 20 km form the fire control system via data link. All required components such as the generator, the fire control computer, antennae and means of communication are deployed on the system frame.  

Fire Control System

The fire control system TOC (Tactical Operations Center) is manned with two operators managing tactical air combat. The center offers modern, ergonomically optimized, role-based and ABC-protected work places controlling and monitoring the entire weapon system. The TOC possesses the relevant data interfaces (real-time and non-real-time) and means of communication connecting it with superior command structures. An open system architecture enables flexible integration in existing and future air defence systems. Furthermore adaptation to operational requirements are possible, since any components can be added or removed (plug & fight). A radar, a TOC and a launcher vehicle offer comprehensive protection with a 40 km radius. The weapon system components are connected via radio- and glass fiber link.

Series Maturity

Diehl Defence masters the design of flexible and modular system configurations in ground-based air defence. Open and standardized interfaces enable easy connection of the missile system with existing and future fire control components. Having successfully completed five test firings in South Africa in 2009, 2010 and 2011, Diehl Defence is approaching its objective of obtaining series maturity for its IRIS-T SLM air defence system starting 2014.