The "fire-and-forget" Stinger missile employs a passive infrared seeker to home in on its airborne target. All U.S. services and 29 other countries have deployed the Stinger missile, launching from a number of platforms: the shoulder-launched Man-Portable Air Defense System (MANPADS), Avenger (HMMWV), the AH-64E Apache helicopter, and Special Operations Black Hawks (MH-60). The Stinger missile is launched by a small launch motor that pushes it a safe distance from the operator before engaging the main flight motor, both solid propellant rocket motors provided by Aerojet Rocketdyne.