Alliant Techsystems has begun flight testing an upgraded HARM anti-radar missile as it looks to expand the supersonic weapon's capability to engage a broader range of targets.

The first development-test firing of the AGM-88E Advanced Anti-Radiation Guided Missile (AARGM) was conducted in late May, and captive-carry tests of the improved multi-sensor guidance system are continuing. Italy is participating in the programme and ATK is discussing potential workshare for LFK/MBDA if Germany joins.

The upgrade adds a millimeter-wave (MMW) terminal seeker, digital anti-radiation homing (ARH) receiver and GPS to the Raytheon AGM-88 HARM. ARH and GPS allow the weapon to detect and locate emitters before launch, while MMW enables the AARGM to continue an attack even if the emitter shuts down - a key weakness of HARM, says Dave Wise, general manager of ATK's advanced weapons division.

US Navy aircraft lack an independent passive targeting system, says Gordon Turner, director strike weapons, so AARGM will autonomously geolocate emitters using its ARH and off-board target data sent directly to the missile on the wing using "national technical means" - likely satellite communications. The same link will be send data back from the missile in flight up to impact, for post-strike damage assessment.

Italy will use the AARGM differently, says Turner. Cued by the targeting system on the Panavia Tornado ECR, the missile will communicate with the launch aircraft using an Italian-unique datalink. Italy and the US Navy plan to upgrade some of their existing inventory of HARMs to AARGM standard to provide the capability to destroy, and not simply suppress, enemy air defences.

"We are working to expand the strike capability against a broader target set, not just radars," says Turner. The supersonic missile has a point-to-point strike mode using GPS targeting and a "point-to-area" capability using GPS guidance then the MMW seeker to "resolve targeting uncertainty", he says.

Twenty AARGM development and operational test firings are planned by the end of 2008, with initial operational capability planned in 2009 for the US Navy and a year later for Italy. Raytheon, meanwhile, flight tested a GPS/INS upgrade for HARM in August last year, and is working with Germany's BGT to launch production.

Source: Flight International