Sidewinder is an IR-guided short-range, supersonic air-to-air missile. It was developed by the Navy for fleet air defense and adapted for USAF fighters. Early versions were used extensively in the Vietnam War.
The AIM-9M is a joint Navy-USAF, all-altitude, all-aspect intercept missile. It has improved defense against IR countermeasures, background discrimination, and a reduced-smoke rocket motor. AIM-9X is the newest joint-funded variant. It employs passive IR tracking, jet-vane steering for increased maneuverability and Joint Helmet-Mounted Cueing System (JHMCS) compatibility for high-angle, off-boresight targeting.
The enhanced AIM-9X Block II was cleared for full-rate production in September 2015 and adds improved lock-after-launch and maneuverability, a new data link for beyond-visual range engagement, enhanced anti-countermeasures, a new fuse, and safer ground-handling characteristics. The Block II+ incorporates the same improvements but is specifically optimized for the F-35. AIM-9X production includes 67 converted AIM-9Ms, 1,289 Block I, and planned joint-service procurement of 11,635 Block II/II-plus (nearly double the number originally planned) through 2035.
FY26 funds increased from FY25, procuring a combined 149. AIM-9X Block II/II+ (X-3) missiles and 24 Captive Air Training Missiles. Development is focused on improving the AIM-9X’s performance against small UAS and ability to defeat advanced IR countermeasures using optical sensing for the next AIM-9X-4 configuration. Block II+ completed operational testing of software and hardware upgrades to enhance performance and add two new, classified capabilities in early FY25, though live testing was hampered by a lack of advanced threat-representative targets.
AIM-9 Sidewinder Technical Data
Contractors: Raytheon; Northrop Grumman (propulsion).
First Flight: September 1953; July 1999 (AIM-9X); 2016 (AIM-9X Block II).
Delivered: AIM-9M 1983; AIM-9X from 2002-2011 (Block I); 2011-present (Block II); 2017-present (Block II+).
IOC: Circa 1983 (9M); November 2003 (9X); September 2016 (9X Block II).
Production: 1,289 (Block I); 11,635 (Block II/Block II+) (planned).
Active Variants: • AIM-9M. Early variant. • AIM-9M-9. Expanded anti-countermeasure capability variant. • AIM-9X. Newest, highly maneuverable, JHMCS compatible variant.
Dimensions: Span 2.1 ft (M), 1.4 ft (X); length 9.4 ft (M), 9.9 ft (X); diameter 5 in.
Propulsion: Mk 36 Mod 11 (9M); Orbital ATK Mk 139 solid-propellant rocket motor (9X).
Performance: Speed Mach 2+, range 10+ miles.
Guidance: Passive IR homing guidance.
Warhead: HE annular blast fragmentation.
Integration: F-15C/D/E/EX, F-16C/D, F-22A (AIM-9X), F-35A (AIM-9X Block II/II+ on external pylons).