Alliant Techsystems (ATK) has submitted a bid to upgrade a worrisome control unit on the AGM-88 high-speed anti-radiation missile (HARM), challenging a rival proposal from the weapon's designer Raytheon.

By entering the race for the $51 million contract to upgrade 500 missiles, ATK is seeking to break into the Raytheon-dominated market for US Air Force anti-radar missiles.

ATK has proposed adapting a control unit, which includes a GPS/INS navigation sysgtem, originally developed for the US Navy AGM-88E advanced anti-radiation guided missile (AARGM) programme.

The AARGM has entered a final round of operational testing before entering service next year, says Bill Kasting, vice-president and general manager of ATK's defence electronics division.

Raytheon also confirms that the company has submitted a bid for the air force contract, which is named "HARM control section modification". As the HARM's original designer, Raytheon has developed and tested a new control section as part of a larger, internally funded upgrade called the HARM destruction of enemy air defence's attack module.

Unlike the navy's AARGM programme, the air force is not asking contractors to upgrade both the missile's control section and guidance system.

The USAF only wants a new control section, which can ensure that the HARM does not lock-on to friendly radars by mistake.

The navy also wanted a guidance system for AARGM to defeat a relatively new enemy tactic. Opposing radar crews had learned to avoid getting hit by shutting down the radar after a HARM is launched. By adding the guidance system, the missile precisely aims for the last-known point where the radar was emitting.

Source: Flight International