In the 1980's Britain, Germany and the U.S. agreed (with support from their other European allies) to produce and procure a replacement for the AIM-9 Sidewinder. The basic idea was that while the U.S. developed AMRAAM (a replacement for Sparrow) for the medium range role, Britain and Germany would produce ASRAAM for short range engagments. Unfortunately the agreement soon flounded with the U.S. initiating its own project to replace the Sidewinder. This left Britain and Germany alone to complete work on ASRAAM.
With the fall of the Communism in the East and the reunification of Germany the Luftwaffe found themselves with large stockpiles of the AA-11 Archer, the USSR's primary short range weapon. Although the West where aware of Archer being more advanced than the AIM-9L Sidewinder Germany quickly concluded that the capabilities had been noticeably under-estimated. In particular the Archer was found to be both more far more manoeuvrable and far more capable in terms of seeker aquisition and tracking. These conclusions led Germany to question certain aspects of the design of ASRAAM, particularly the lack of thrust vectoring to aid manoeuvrability. On-going discussions between Germany and Britain eventually failed in 1990 when no short or medium term compromise could be reached. Subsequently Germany withdrew from the ASRAAM project, Britain continued alone to produce and procure ASRAAM.
During this time BGT (Bodenseewerk Geratecknik) had continued work on a new high resolution scanning imaging infra red seeker. In 1995 Germany announced its intention with several partner nations (Italy, Sweden and Greece, later joined by Canada and Norway) to commence development of its own short range weapon The weapon was to be named, IRIS-T, Infra Red Imagery Sidewinder Tail-controlled with workshare arrangements thus; Germay 46%, Italy 19%, Sweden 18%, Greece 13% the remainder split between Canada and Norway. The system would build upon BGT's involvement in production of the existing AIM-9 Sidewinder as well as its seeker work. As with ASRAAM the IRIS-T retains complete interoperability with AIM-9. Any aircraft capable of carrying and firing Sidewinder will be capable of launching IRIS-T.
Although based on the AIM-9 design IRIS-T improves upon it quite substantially in practically every area. The missile consists of basically five sections; guidance, fuze, warhead, motor and tail control. The guidance section contains a BGT designed scanning imaging Indium-Antimonide infra-red sensor. The array has a resolution of 128 by 128 pixels which combined with digital signal processing (provided by a SAAB built DSP) gives the missile an ability to see its target and even aim for certain specific sections. In addition the seeker offers an off-boresight capability of 90 degrees in all directions. This gives it the ability to be launched over the shoulder via an appropriate cueing system (eg. a Helmet Mounted Sight), targetting data can also be taken from the launch platforms radar. Initial guidance is provided by a strap-down inertial navigation system built by Litton Italia. Behind the sensor sits an active radar based fuze built by Alenia-Marconi. This provides both range and range-rate information allowing the missile to detonate its warhead at a pre-determined distance form the target.
Next in line is a dual-layer High Explosive fragmentation warhead designed and built by Greece's GPCC. Behind this sit the main propulsion and control systems. A new motor built by FiatAvio of Italy and Nammo of Norway is included which utilises a smokeless propellant arranged in a star-shaped formation within the combustion chamber. This section also provides the attachment point for four wings providing additional lift. The rear most section, the responsibility of Canada's AlliedSignal contains the thrust vectoring nozzle as well as four fins. The nozzle, which provides for flight control utilises four vanes placed within the exhaust. By directly controlling the position of these the thrust can be vectored in any required direction. Such an arrangement provides a large increase in achievable manoueverability, turns in excess of 50g are made possible.
The Swedish Air Force has already commited to purchasing IRIS-T for its JAS-39 Gripen fleet when deliveries begin in 2002. To enable deployment SAAB-BAE Systems have already carried out test flights of a Helmet Mounted Sight for the Gripen allowing IRIS-T to be fully utilised. Beyond Germany and Sweden, Norway is also expected to purchase the weapon as a replacement for AIM-9 aboard its F-16's. In addition both Denmark and Belgium are interested in purchasing the weapon.
In October 2000 the first air launched firings of the missile occured from F-16's of the Hellenic Air Force. This was followed first in March 2002 by a pre-programmed launch against a drone target and later by a seeker guided firing in April 2002. The missile, launched from an F-4 Phantom flying off the coast of Sardinia successfully tracked and brought down the drone. According to BGT development remains on track and initial production versions of the missile are due to be made available by mid-2002 with full production occuring in late-2002/early-2003. IRIS-T is set to gain full operational clearance before the end of 2005. This date should mirror the first fully operational Eurofighter Typhoon squadrons in Luftwaffe service, IRIS-T being the primary short range weapon for German Eurofighters.
* : Note that all ranges quoted are based on mean figures from various data sources. Actual achievable range will depend on a great number of factors and may be no where near those quoted.