Diehl Defence, a German arms manufacturer, has announced a contract for further development of the IRIS-T Block II, a new variant of the fairly widely-known IRIS-T air-to-air missile operated in over a dozen nations. The weapon is integrated with aircraft such as the Eurofighter, Tornado, some versions of the F-16, the Spanish F/A-18, as well as more niche KF-21 and F-5E fighters. It is also used with insignificant modifications in the short-range IRIS-T SLS air defense system, proving itself daily in Ukraine, among other operators.
The official message from Diehl is short on details and refers to the contract in past tense recalling the signing concluded with BAAINBw (Bundeswehr procurement department) back in late December 2024. The agreement encompasses the development and serial production of the IRIS-T Block II — and that's it. Neither the delivery deadlines, the volume, nor the essence of the modernization planned for the missile and its difference from the original IRIS-T were specified.
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Despite such laconic reporting, there's actually some extra information about the upgrade disclosed previously, all collected by Defense Express. For starters, in the same December, the Bundestag mentioned it among the 38 defense projects greenlighted with an investment of €21 billion total, including 25 million euros for the works on IRIS-T Block II specifically. This relatively small amount of funds for research may explain why Diehl decided not to elaborate on the scope of work.
Especially since the content of the IRIS-T Block II project was earlier described by Diehl Defence Chief Program Director Harald Buschek at the ILA Berlin Air Show 2024, in June. According to Buschek, the updated version of the missile will receive a new homing head, improved electronics, and the ability to exchange data mid-flight.
Therefore, the IRIS-T Block II is expected to retain the same launch range (25 km in air-to-air variant) and warhead weight (11.4 kg). On the flip side, the response speed, range, and quality of target acquisition, noise resistance, and other parameters derived from its electronics component will reach a new level.
The mid-flight data exchange with the aircraft should also allow the missile to clarify target data and receive re-targeting commands post-launch, or to successfully intercept the threat when discharged blindly, guided by external target designation until it locks with own seeker.

Logically, after all these changes are integrated with the air-launched IRIS-T, similar innovations could be replicated in the surface-launched IRIS-T SLM anti-aircraft missile, which has a range of 40 km. Reports suggest that these upgrades are already integrated into the latest iteration of the missile, the long-range IRIS-T SLX, which boasts a maximum threat engagement distance of 80 km.
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