A Swiss F-18 was recently conducting live firing training, using American AIM-9P Sidewinder missiles. When the jet fired its Sidewinder, the missile dropped away from the aircraft, and then fell apart. An investigation is being conducted. The missile in question was apparently quite old. AIM-9Ps are export versions for customers who were not eligible to receive the classified components found in the AIM-9L (a 1970s/80s version, long since replaced by the M and X versions).
While Sidewinders have nearly 300 kills world-wide to date, most rarely leave an ammo bunker. Thus for every 380 Sidewinders manufactured so far, only one has brought down an enemy aircraft. Only about one percent of all Sidewinders ever even got used in combat. The vast majority of the 110,000 built, spent their careers being carried by fighters, or, more frequently stored away, waiting for a war or a training flight. For that reason, the missile is designed for easy upgrades. Many of those in service have some components that are over twenty years old. And nearly all AIM-9s end up being scrapped eventually, dying from old age.
Half a century ago, the U.S. Sidewinder air-to-air heat seeking missile (AIM-9A) scored its first kill, when a Taiwanese pilot, in an American F-86, brought down a Chinese MiG-17. The Sidewinder entered service in 1956, and has since been the most effective air-to-air missile ever produced. The latest model, the AIM-9X, entered service in late 2003, and thus missed the Iraq invasion. But over the last eight years, the 9X has been fired in nearly 140 tests, including many that used drone aircraft as targets, and live warheads on the Sidewinders.
The first Sidewinder (AIM-9B) was 9.28 feet long, weighed 156 pounds and had a max range of five kilometers . The most current one (AIM-9X), half a century later, is 9.5 feet long, weighs 191 pounds and has a max range of over 20 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.
The missile itself, is more like an aircraft component, than an expendable weapon. The Sidewinder was originally conceived and developed in the shadows and off the books. The U.S. Navy engineers who created it over a ten year period, had to scrounge for money and materials, and many volunteered their labor. The basic concepts of the Sidewinder were developed during World War II, but producing a practical and reliable weapon seemed far beyond current technology. By the end of the 1950s, American air warfare experts believed that the missile was going to replace cannon as the main armament of fighters. That didn't happen right away, but gradually it did.