October 3, 2014:
Three years after introducing the latest version of the American anti-radiation missile, the AGM-88E HARM (High speed Anti-Radiation Missile), a new version (88F) is completing its performance tests. The AGM-88F has a GPS guidance added (with less accurate but jam-proof INS as a backup) added. The older AGM-88D also used GPS so that the missile, which normally homes in on radar transmissions, could be used to attack targets by location alone. The F model expands on basic GPS capabilities and also includes other features that assist in defeating enemy electronic defenses. What the GPS/INS provides is for a way for HARM to act on previous intelligence (about where an enemy radar is) while also using its radar signal homing capability and new anti-decoy features. Many countries now use a decoy emitter that send out a fake radar signal to lure the HARM away from the real radar. The 88F model uses GPS and more sensors and new software to get around all known deceptions (and some that haven’t been invented yet).
It was only in 2011, after eight years of development that the 88E entered service. Shortly thereafter a government oversight office announced that the AGM-88E was not able to accomplish its mission. The flaws in question were classified and the navy (which developed the AGM-88E) insisted that the new missile was more effective than its predecessor and the air force and marines also wanted to see the AGM-88E in service. There was no disagreement over remaining problems with the missile. The military believed that, despite the flaws, the AGM-88E was an improvement and that it should be issued for use.
The military got their new missile, despite continued opposition. Since the problems are largely classified, the public will not know what was really at stake for some time (until the details are declassified or leaked). There are a lot of new features in the AGM-88E and it’s probably some of these that the military insists should not stop the missile from being delivered to combat units.
The first 88E production models were delivered in 2010. This included testing for use on the new electronic warfare aircraft, the EA-18G, which entered service in 2011. AGM-88E testing ran into many problems in the three years before it entered service and there were more hardware failures than expected. The military admits that it is still working on some of these issues but that, in its current state, the AGM-88E is good to go.
The AGM-88 moves at high speed (2,200 kilometers an hour or 36 kilometers a minute) to hit targets 100 kilometers away. The D version of the AGM-88 costs nearly $100,000 each. Another version uses more complex sensors that can detect and guide the missile to a wide variety of radar signals. These versions cost about $300,000 each. GPS enables HARM (or the aircraft carrying it) to locate radar when it is turned on, store the GPS location, then goes after the target regardless of whether the ground radar is turned on or off. Over 24,000 AGM-88s, of all types, have been produced in the last three decades.
The new AGM-88E/F designs use a more complex and expensive approach to nailing enemy air defense radars (looking for targets) that are turned on briefly and quickly turning off power. This is an attempt to avoid detection destruction by missiles (like all AGM-88s) that home in on radar signals. The AGM-88E remembers where the radar is when it was on, however briefly, and carries its own high resolution (millimeter wave) radar to make sure it gets the radar. Finally, the AGM-88E can transmit a picture of the target, just before it is hit, so the user can be certain of what was taken out. The AGM-88E, also called the Advanced Anti-Radiation Guided Missile (AARGM), was developed jointly by U.S. and Italian firms. The original AGM-88 entered service in the 1980s. The original 1960s anti-radiation missile (ARM) quickly evolved into the HARM. Currently, there are orders for over 2,000 AGM-88Es from the U.S. Navy and Marine Corps, Italy, and Germany.