A deadly-effective supersonic missile, designed to take out enemy air defenses, is getting a major upgrade to make it even more lethal than before. I have an article in this month's Defense Technology International about it.
Soon after radar-guided anti-aircraft missiles became a threat, planners realized that the simplest way to stop them was to take out the radar. These radars make an easy target; in radio terms, they are equivalent to lighthouses, radiating brightly. So in 1958 the U.S. introduced the Shrike, an "Anti-Radiation Missile" that homed in on enemy radar and proved invaluable in the Vietnam War. The modern successor is the AGM-88 HARM High Speed Antiradiation missile, which has longer range and a speed of over mach 2. "No U.S. aircraft has ever been lost to surface-to-air missiles when HARM has been flying cover," Mike Vigue, HARM Growth Manager at Raytheon, told me.
The problem with this type of missile is that it relies on the enemy radar being turned on. Once they spot a missile barreling towards them, the operators can turn off the radar so it has nothing to home in on. So the mission is known as Suppression of Enemy Air Defence or SEAD: you're not likely to kill them, but you can force enemy radar to shut down, making the skies safe for friendly aircraft.
All that changes when you can fit HARM with a GPS module that allows it to accurately pinpoint the location of the radar emitter. The addition means that even if the radar turns off, the missile can still hit it precisely.
Raytheon's upgrade is called HDAM, for HARM Destruction of Enemy Air Defenses Attack Module. It's being built for the Air Force. And it incorporates both GPS and an inertial measurement unit with a fiber-optic gyro. Raytheon won’t say exactly how accurate it is, but unlike other anti-radiation missiles which rely on a shrapnel warhead, HDAM has achieved "metal on metal" hits on radar targets, both emitting and non-emitting.
The Navy, meanwhile, has ordered the AGM-88E HARM , otherwise known as the Advanced Anti-Radiation Guided Missile (AARGM), from Alliant Techsystems. This includes GPS guidance like HDAM, as well as a range of other features.
Both weapons give a new capability, and rather than Suppression of Enemy Air Defenses, they're now being described as being for Destruction of Enemy Air Defenses – DEAD.
And they can target more than radar. The GPS guidance also means that the upgraded missiles can be programmed to hit a precision target from sixty miles away, making HARM the only high-speed surface-to-air weapon in the inventory. This gives it obvious utility against fleeting, time-critical targets.
The Navy are spending over a billion dollars on acquiring 1,750 missiles. The HDAM is cheaper at "much less" than $100k a missile, but the Air Force may be able to get their upgrades without spending a dime. This is because Raytheon has a "replacement exchange in kind" deal under which the company takes obsolete missiles (such as old stockpiled Sidewinder, Maverick or HARM missiles) and refurbishes them for foreign customers - and gives the Air Force credit to purchase other Raytheon products like the HARM upgrades.
(zinio/wired/defense technology international)