AGM-158 JASSMAGM 158 JASSM desk model. Under the Joint Air to Surface Standoff Missile (JASSM) program, the AGM 158 air to surface missile was designed for launch from outside area defenses to kill hard, medium hardened, soft, and area type targets. Fixed and mobile targets beyond the range of enemy air defenses are also easy pickings for this missile, as it had the capability to fly autonomously after launch over a low level, circuitous route to the target area.