Aircraft

Raytheon has adapted the heat-seeking AIM-9X to strike moving targets on the ground or in the water, adding another new capability for the formerly air-to-air-only missile.

The modification allows the same AIM-9X to strike both air and ground targets. Jeff White, Raytheon's business development manager for AIM-9X, declines to describe the modification in detail, but says it involves only software changes. The AIM-9X infrared seeker, proximity fuse and blast/fragmentation warhead remain unchanged.

During a 23 September Gulf of Mexico test, a US Air Force F-15C fired the air-to-surface AIM-9X and hit a speeding "cigar boat", a type commonly used by drug smugglers. "The missile went right through the boat," says White.

The F-15C test follows a previous shot by an F-16 at a similar target, which also scored a hit on the boat, he adds.

The project to develop the air-to-surface mode for the AIM-9X began with a request from the USAF in March 2007. Although the AIM-9X is primarily an air-to-air missile used in short-range engagements, USAF officials saw a need to make it multi-purpose.

"Maybe you're flying an F-15 that only has air-to-air weapons," says White. "The F-15C only carries air-to-air weapons. Well, now the pilot has an air-to-ground weapon."

The same concept also applies to fighters that can carry a mix of air and ground munitions. For example, if a Boeing F/A-18 is asked to strike a ground target after dropping all its bombs, the pilot could still use the AIM-9X, says White.

Raytheon has greatly expanded the missile's capability since introducing the AIM-9X Block 1 missile in 2003. The company is completing developmental testing on Block 2, which adds a smaller fuse that allows room to insert a one-way datalink for lock-on after launch capability.

The latter upgrade also enables Raytheon to convert the AIM-9X into a surface-to-air missile, launched from a high-mobility multipurpose wheeled vehicle (HMMWV). Raytheon is discussing the concept with US government agencies, says White.

Meanwhile, a submarine-launched variant of the AIM-9X is being prepared for the US Navy. Raytheon has demonstrated underwater launch of a Sidewinder-shaped missile, and is in talks with the USN to launch a programme of record in 2012.

The goal of the Littoral Warfare Weapon would be to equip submarines with a missile to strike helicopters equipped with dipping sonars and torpedoes. "If submarines get caught in the shallows, they need some defence," says White.