Ramon Lopez/WASHINGTON DC
A new seeker for the Raytheon AGM-88 HARM anti-radiation missile that will allow engagement of non-emitting targets is to undergo US Navy captive carry tests later this year.
The flight testing is part of the Advanced Anti-Radiation Guided Missile (AARGM) technology demonstration programme, which is developing next-generation missile technologies, including a dual-mode seeker, as well as advanced propulsion and airframes.
HARMs fitted with AARGM technologies will not be fielded until 2008, but the USN's lethal suppression of enemy air defences plan includes interim improvements that could enter service earlier. Today's HARM is designed to knock out continuously emitting air-defence radars. The USN's three-step programme will make the weapon more capable against air-defence systems with radars that have shut down.
Improvements include the AGM-88B Block IIIA and AGM-88C Block V, which have software improvements that allow the HARM to maintain target lock-on, even if the emitter closes down. Fielding starts this month.
A programme involving the USA, Germany and Italy - known as the International HARM Upgrade Programme, or AGM-88DBlock IV - incorporates software and hardware improvements. The latter includes replacement of mechanical guidance gyros with a global positioning system/inertial measurement unit (GPS/IMU). The work is 13 months into a four-year engineering and manufacturing development (EMD) effort, with work split between Alenia Marconi Systems in Italy, BGT in Germany and Raytheon.
Preliminary AARGM seeker work was undertaken between 1990 and 1996 by Science and Applied Technologies. The current Phase III technology demonstration includes development of a 254mm (10in) brassboard prototype incorporating a passive anti-radiation homing sensor with a conformal antenna coupled to an active W-band millimetre-wave terminal seeker and a GPS/IMU navigation suite.
Successful captive carriage tests could lead to a series of live firing trials and possibly an EMD programme. Two shots to validate separation characteristics and digital avionics performance would be followed by four more live firings through to the middle of next year.
Project manager USN Capt Robert Russell says: "The technology holds a lot of promise." He says a higher-speed HARM is envisioned, with Raytheon proposing a dual inlet variable-flow ducted rocket. Russell says the AARGM had been directed towards an AGM-122 Sidearm anti-radiation missile replacement, but the Sidewinder derivative is being phased out. He says a Boeing AGM-114 Hellfire variant might replace the Sidearm.
Source: Flight International