Sidewinder Guided Missile

The Sidewinder guided missiles, AIM-9 series (fig. 3-8), are supersonic, air-to-air weapons with passive infrared target detection, proportional navigation guidance, and torque-balance control systems. They are capable of being launched from the A-6, F-14, and F/A-18 aircraft. The AIM-9 series missiles are issued to the fleet as AURs. The components of the ATM-9L-1 are identical to the AIM-9L/M except that a training warhead is substituted for the tactical warhead in the ATM-9L-1. The AIM-9L/M missile is used strictly for tactical purposes. The ATM-9L-1 missile is used for pilot training in target acquisition and missile firing.

The Sidewinder guided missile is approximately 113 inches in length, 5 inches in diameter, weighs approximately 190 pounds, and consists of five major components. These components are the guidance and

Figure 3-8.-AIM-9 series Sidewinders guided missile. 3-11

control section, the target detector section, the S&A device, the warhead section, and the rocket motor section (fig. 3-9).

The guidance and control section consists of the following three major assemblies:

1. An infrared seeker assembly, which is used for detecting the target.

2. An electronic assembly, which is used for converting detected target information to tracking and guidance command signals.

3. A gas servo assembly (which consists of a gas generator, manifold, pistons, rocker arms, electrical solenoids, and thermal battery), where the electrical guidance commands are converted to mechanical movement of the control fins.

Four BSU-32/B control fins are mounted on the guidance and control section to provide aerodynamic lift and course alterations to the missile during free flight.

They are movable surfaces that are electrically controlled and pneumatically operated by the gas servo assembly, The missile's umbilical cable is also attached to the guidance and control section. A shorting cap/dust cover must be installed on the umbilical connector at all times when the missile is not electrically connected to the LAU-7 launcher. The umbilical cable provides the necessary path for the exchange of electronic signals between the missile and aircraft before missile launch. It also provides a connection to the launcher-mounted cooling gas supply, which prevents the electronic components of the guidance and control section from becoming overheated during operation before missile launch. The umbilical cable is sheared off at missile launch.

The target detector (TD) is a narrow-beam, active-optical, proximity fuze system. The purpose of the TD is to detect the presence of an air target within the burst range of the missile warhead and generate an electrical firing signal to the S&A device.

Figure 3-9.-AIM-9 series Sidewinders guided missile (exploded view). 3-12

The S&A device attaches to the target detector and is located between the TD section and the warhead section. The S&A device contains an interrupted firing train that is aligned by an acceleration arming device. It contains the necessary high explosives, switches, and circuits to initiate detonation of the warhead.

The WDU-17/B warhead (used in the AIM-9L configuration) is an annular blast fragmentation warhead that consists of a case assembly, two booster plates, an initiator, high explosive, and fragmentation rods. The explosive output from the S&A device is transferred through the initiator to the booster plates. The initiation is then transferred through the explosive-loaded channels of the booster plates to the booster pellets at each end of the warhead. Detonation of the booster pellets sets off the high explosive, causing warhead detonation.

The WDU-9A/B warhead (used in the ATM-9L-1 configuration) is mechanically interchangeable with the WDU-17/B tactical warhead The WDU-9A/B contains a smoke-flash mix with CH-6 booster to provide visual observation of the missile/target hit.

The Mk 36 Mod 7 rocket motor uses a single-grain propellant. A nonpropulsive head closure, located on the forward end of the motor tube, blows out if the motor is accidentally ignited without the warhead installed, making the motor nonpropulsive (a fire hazard vice a missile hazard). The Mk 36 Mod 8 rocket motor is basically identical to the Mod 7 motor except that the Mod 8 motor is equipped with a safe-arm ignition assembly. The purpose of this assembly is to prevent accidental or inadvertent rocket motor ignition. The safe-arm ignition assembly must be manually rotated to the armed position before flight. This is accomplished by the use of a hex-head T-handle.

Four Mk 1 Mod 0 or Mod 1 wings are attached to the aft end of the motor tube. They provide aerodynamic lift and stability during flight. Each wing has a rolleron assembly that provides pitch, yaw, and roll stabilization during free flight. When the missile is fired, the rolleron is uncaged by acceleration and is free to move through its longitudinal axis during flight. The rolleron wheel is designed so that the passing airstream causes it to spin at a very high speed, thus acting as a gyroscope, which helps to stabilize the missile and reduce roll during flight.

For further information about the AIM-9L/M and ATM-9L-1 Sidewinder guided missile, you should refer to the Sidewinders Guided Missile AIM-9L and Training Missile, NAVAIR 01-AIM9-2.

Advanced Medium Range Air-to-Air Missile (AMRAAM)

The AMRAAM is an all-weather missile (fig. 3-10). Aircraft currently scheduled to carry the missile are the

Figure 3-10.-AIM-120 AMRAAM guided missile 3-13

F-14 and F/A-18 aircraft. The AIM-120 is an AUR that consists of a guidance section, armament section, propulsion section, and control section.

The guidance section consist of a radome, seeker components, electronics unit, inertial reference unit, target detection device, batteries, power converter, and related harnesses and hardware.

The armament section includes a WDU-33/b fragmenting warhead, Mk-44 booster, and a FZU-49/B safe and arm fuze (SAF).

The propulsion section consists of a dual-thrust, solid-propellant, low-smoke, rocket motor, a blast tube and exit cone, and an arm/fire device (AFD).

The control section includes four independently controlled electromechanical actuators, four thermal batteries, a data link assembly, and associated hardware. The control surfaces are locked in position by gas pressure-operated mechanical locks during ground handling and captive carry. During launch, a pyrotechnic gas generator creates enough gas pressure to unlock the control surfaces.