December5, 2006: The 1960s era HARM (High-speed Anti-Radiation Missile) has received a major upgrade, and is now being called "HDAM" (HARM Destruction of enemy air defense Attack Module). The original HARM was a missile guided by signals being put out by enemy radars. HDAM overcomes a common trick radar operators used to protect themselves, by turning the radar off. HARM got around that by homing in on the last location of a transmission. HDAM goes one step further, and uses GPS (with inertial guidance as a backup) to take the missile to where some over system (satellite, aircraft or UAV) had located a radar. Tests have demonstrated that HDAM is accurate enough to destroy radars this way. HDAM can still find radars the old fashioned way, if the radar is turned on. More importantly, the HDAM can be fired far enough away from a radar, that the anti-aircraft missiles the radar is spotting for, are less of a risk.

While the United States produced the first HARM missiles, several other nations now make them as well.