In the mid-1980s, a new "sidewinder" type missile appeared. The AA-11 Archer entered service in what was the Soviet Union, primarily being used on the MiG-29 and Su-27. The Archer has a range of 20-40 kilometers, depending on the version, and a 16.3-pound warhead. Among the features it included was an off-boresight capability (being able to turn sharply flight) using a helmet-mounted sight. The Archer clearly had eclipsed the AIM-9L/M Sidewinder, which had a range of 16 kilometers and a 25-pound warhead. The Python 4, an Israeli IR-homing missile, which also had a helmet-mounted sight, also was outperforming the Sidewinder (15-kilometer range, nearly as much as the Sidewinder, and a 24.25-pound warhead at Mach 3.5).
The Sidewinder had been slated for replacement by the AIM-132 ASRAAM (Advanced Short-Range Air-to-Air Missile), which had a range of 15 kilometers and a 22-pound warhead. However, the U.S. backed out of the program, and went to the AIM-9R. ASRAAM was eventually adopted by the RAF and Germans. However, the AIM-9R, which featured a much more accurate imaging infra-red (IIR) seeker, and a range of 19 kilometers, was cancelled. A new Sidewinder was still needed as the MiG-29 and Su-27, both armed with the AA-11, proliferated across the globe. The answer came in the AIM-9X.
The AIM-9X had a range of 40 kilometers, in the same class as the AA-11, it also was designed to include a helmet-mounted sight, which is now entering service. The system uses a number of components from the AIM-9M (mostly the motor and the warhead). In addition to longer range than the AIM-9M, the AIM-9X also has staring IIR guidance.
Which is better? In this case, the Archer has a few advantages. It has been in service longer, and pretty much has all of the kinks worked out of it. The AIM-9X is new, and will need some time to work out the problems that will crop up in service. That said, the Sidewinder comes with a lengthy combat record, covering combat over the Taiwan Straits, the Gulf of Sidra, Vietnam, and the Middle East and 270 kills. The odds are in favor of the Sidewinder reclaiming the title of being the best IR-homing air-to-air missile. Harold C. Hutchison (firstname.lastname@example.org)
Sidewinder vs. Archer. The AIM-9 Sidewinder has long been the standard by which infra-red (IR, or heat seeking) homing air-to-air missiles are judged. First introduced in 1954, and quickly proven in combat by Taiwan against Communist China, the missile is entering its sixth decade of service, and is a classic that has been continually improved.