SiAW is the Air Force’s developmental next-generation supersonic air-to-surface weapon for use against advanced integrated air defenses high-value and rapidly relocatable targets, including missile launchers.
SiAW builds on the Advanced Anti-Radiation Guided Missile-Extended Range aimed at confronting “2025+” threats that the AGM-88 HARM is unable to counter and is specifically tailored for employment on the F-35A. The missile is expected to outrange and possibly outpace the approximately 180-mile Mach 4 AARGMER improving aircraft and weapon survivability against modern defenses.
The missile incorporates highly aft tailplanes and blended conformal strakes for enhanced maneuverability, and jam-resistant INS/GPS guidance and antiradiation seekers, as well as counter-countermeasures. It also incorporates open-architecture software to keep pace with evolving threats.
Northrop Grumman was awarded the initial $705 million development and integration contract in September 2023, ahead of the first delivery of a test weapon in 2024. An F-16 successfully conducted the first inert, airborne separation over the Eglin range on Nov. 7, 2025. USAF plans to conduct a series of four guided test shots prior to Northrop Grumman delivering a completed prototype before an aggressive IOC target of this year.
Initial integration is planned on the F-35A—carrying two weapons internally—followed by the F-15E, F-15EX, and B-21.
Stand-In Attack Weapon (SiAW) Technical Data
Contractor: Northrop Grumman.
First Flight: N/A.
Delivered: 2024-present.
IOC: 2026 (planned).
Active Variant: •SiAW. Next-generation anti-radiation air-to-ground guided extended-range missile.
Dimensions: Unknown.
Propulsion: Unknown.
Performance: Projected Mach 4+, range 180+ miles.
Guidance: GPS/INS and broad-frequency anti-radiation seeker.
Warhead: Unknown.
Integration: Planned: B-21, F-16, F-15E, F-15EX, F-35A.