June 19, 2009: For the second time, an AIM-9X air-to-air missile was fired from the ground. The latest test successfully hit a drone aircraft. The U.S. Marine Corps sponsored the tests, as it is seeking to use the AIM-9X in a vehicle based anti-aircraft system.

The AIM-9X is the most recent model of the Sidewinder, and entered service in late 2003. But over the last eight years, the 9X has been fired in over 150 tests, including many that used drone aircraft as targets, and live warheads on the Sidewinders.

Half a century ago, the first Sidewinder (AIM-9B) was 9.28 feet long, weighed 156 pounds and had a max range of five kilometers . The AIM-9X is 9.5 feet long, weighs 191 pounds and has a max range of over 20 kilometers (fired from the ground, ten kilometers). The AIM-9X can go after the target from all angles, while the AIM-9B could only be used from directly behind the target. The AIM-9X is about seven times more likely to bring down the target than the AIM-9B.

American warplanes have controlled the skies for over sixty years, and U.S. ground forces have not felt compelled to spend a lot on anti-aircraft systems. There is a portable missile (Stinger) for the troops, mainly to be used against enemy helicopters at a range of up to four kilometers. But there's never been much in between stuff that you can carry on your back, like Stinger, and high end systems like Patriot (which has never shot down an enemy aircraft, but has destroyed two friendlies so far.)

Instead, there have been improvised systems, that usually had vehicles equipped with larger heat seeking missile, like the Sidewinder. Such a system, called the Chaparral, was used by the U.S. Army from the late 1960s to the late 1990s, armed with an earlier model of the Sidewinder. A replacement system, Avenger, now using Stinger missiles, was introduced in 1993. But what the army really wanted was SLAMRAAM, using a larger, radar guided, air-to-air missile (AMRAAM).

 SLAMRAAM has been in development for eight years. The army has been criticized for taking so long, especially since the Norwegians put together such a system in the late 1990s. This is what inspired the U.S. Army and Marines to do the same. But it was not a high priority project. The main technical problem with these systems is integrating the missiles control system into an air defense radar network. The Norwegians simply used the older HAWK missile system (which Patriot replaced). The U.S. Department of Defense was supposed to just adapt the Norwegian system for American use.

 Two years ago, The U.S. Marine Corps cancelled their version of SLAMRAAM (called CLAWS, or Complementary Low Altitude Weapons System.) The marines didn't have the money, and didn't see an urgent enough need to go find the money. Air defense was not a big deal when your jet fighters rule the skies.

 The U.S. Army had started work on SLAMRAAM two years after the marines began developing CLAWS. This system mounted four U.S. Air Force AMRAAM radar guided air-to-air missile on a hummer. A firing battery consists of one fire-control center, a radar (with a 75 kilometer range) and four to eight hummers carrying missiles. The missiles have an effective range of 25 kilometers, and can knock down cruise missiles, as well as helicopters. It was the need to knock down cruise missiles that has kept the army going.

 The AMRAAM is the most modern air-to-air missile in American service, and has its own radar for making its final approach to its target. The SLAMRAAM concept, as first developed in Norway, has been adopted by several other countries (including Spain and Kuwait).

A box launcher is used by the Norwegian system (called NASAMS). The ground launched AMRAAM can hit targets as high as 13,000 feet. NASAMS was developed so that it could easily work with different search radars. The 350 pound AMRAAM SAM costs more (about $600,000 each) compared to the air-to-air version (about $380,000), but is basically the same missile. The twelve foot long AMRAAM has a fifty pound warhead, and can take down just about anything that flies, including wide-body commercial transports.

 The marines are interested in a SLAMRAAM armed with AIM-9X, as the missile would be less than a fourth the cost of the AMRAAM. Meanwhile, the army is taking heat from Congress over the delays in getting SLAMRAAM into service. But with a war on, SLAMRAAM is a low priority project that is being given just enough money and attention to keep the lights on, not to push the system out the door and into the hands of the troops who don't really need it at the moment. Meanwhile, SLAMRAAM has been sold to several foreign customers.