Sidearm Credit - via Andreas Parsch

Radar-homing missile based on converted ex-AIM-9Cs.

Historical Essay © Andreas Parsch

Motorola AGM-122 Sidearm

In the early 1980s, the U.S. Navy looked for a way to make use of the stocks of semi-active radar homing AIM-9C Sidewinder missiles, which had been phased out of service. The NWC (Naval Weapons Center) at China Lake developed the Sidearm (for "Sidewinder Anti-Radiation Missile"), a conversion of the AIM-9C to an air-to-ground anti-radiation missile. The first test firing of a prototype conversion occurred in 1981, and in 1984, Motorola was awarded a contract to convert existing AIM-9C missiles into AGM-122A Sidearms. The original narrow-band passive radar seeker of the AIM-9C was substituted by a broader-band seeker, and the DSU-17/B proximity fuze of later Sidewinders was also incorporated into the AGM-122A. While Sidearm is less capable than modern anti-radiation missiles (like AGM-88 HARM), it is still a cost-effective alternative against low-tech threats. Between 1986 and 1990, more than 700 missiles were delivered for use by the U.S. Marine Corps.

There is also an inert training version designated ATM-122A, and the CATM-122A is a version for captive (non-firing) training.

When the AIM-9C stocks were exhausted at the end of the 1980s, it was proposed to build new missiles as improved AGM-122B. The AGM-122B was to receive a new guidance and control system using reprogrammable EEPROM memory boards. However, this proposal was not adopted, and the AGM-122B was cancelled. The designation CATM-122B was also already allocated for a planned captive-carry training version.

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for AGM-122A:

[1] Norman Friedman: "World Naval Weapons Systems, 1997/98", Naval Institute Press, 1997
[2] Hajime Ozu: "Missile 2000 - Reference Guide to World Missile Systems", Shinkigensha, 2000

Manufacturer: Ford/Raytheon. Total Mass: 84 kg (185 lb). Core Diameter: 0.13 m (0.42 ft). Total Length: 2.87 m (9.41 ft). Span: 0.64 m (2.09 ft). Standard warhead mass: 10 kg (22 lb). Maximum range: 8.00 km (4.90 mi). Guidance: Anti-Radar Homing.