Mission: The mission of Patriot is to provide protection for critical assets and maneuver forces belonging to corps and echelons above corps (EAC) against airborne threats from very low to very high altitudes. The objective of Patriot operations at all levels is to disrupt and destroy the enemy's ability to mount effective air operations.

SYSTEM DESCRIPTION - BATTALION FIRE DIRECTION CENTER

The major end items of the Patriot battalion fire direction center (FDC) are the Information and Coordination Central (ICC) (AN/MSQ-ll6), Electric Power Unit (EPU II) (PU 789), Communications Relay Group (CRG) (AN/MRC-137) and Antenna Mast Group (AMG) (OE-349/MRC).

INFORMATION AND COORDINATION CENTRAL

The ICC is the C3 center of the Patriot battalion during AD operations. The ICC consists of a lightweight weather tight shelter mounted on a 5-ton cargo truck (figure 1). The shelter provides shielding from radio frequency interference (RFI) and electromagnetic pulse (EMP) radiation. It is equipped with two externally mounted air conditioners that cool, heat, and ventilate the interior. An externally mounted gas particulate filter unit (GPFU) is used in NBC situations to provide clean air for crewmembers.

The ICC contains two consoles that are manned by the tactical director (TD) and tactical director assistant (TDA). Between the two consoles is an ICC status panel that displays the status of all battalion fire units (FU).

Figure 1

ELECTRIC POWER UNIT

The EPU II is the prime power source for the ICC and CRG. The EPU II consists of a 30 kw, 400 Hz generator mounted on a trailer and towed by the ICC or CRG. Two generators will be used for the ICC and two generators for the CRG.

COMMUNICATIONS RELAY GROUP

The CRG provides a multirouted secure, two-way data relay capability between the ICC, its assigned fire units, and between adjacent units. The CRG also provides the capability for both data and voice exit and entry communication points with elements that are external to Patriot.

ANTENNA MAST GROUP, TRUCK MOUNTED, OE-349/MRC

The AMG (figure 2) is a mobile antenna mast system used to carry the amplifiers and antennas associated with the UHF communications equipment located in the ECS, ICC, and CRG. Four antennas are mounted in two pairs, are remotely controlled in azimuth, and can be elevated to heights up to 100 feet, 11 inches, above ground level.

Figure 2

SYSTEM DESCRIPTION - FIRING BATTERY

The heart of the Patriot battery is the fire control section and associated launchers. The major end items are the Engagement Control Station (ECS) (AN/MSQ-104), Electric Power Plant (EPP III) (M977EPP), Radar Station (RS) (AN/MPQ-53), eight Launching Stations (LS) (M901) and Antenna Mast Group (AMG) (OE-349/MRC). A general description of end items including the purpose and characteristics follows.

ENGAGEMENT CONTROL STATION TRUCK MOUNTED AN/MSQ-104

The ECS is the operational control center of the Patriot FU (figure 3). It contains the WCC, man/machine interface and various data and communications terminals. The ECS is air-conditioned and includes protection devices for use in NBC and EMP environments.

The ECS shelter provides shielding from RFI and is a weather-tight enclosure with appropriate air inlet and exhaust ports for the environmental control systems. The left side as seen from the doorway includes three UHF RRT and a voice communications station. The right side includes the very high frequency (VHF) DLT, radar weapon control interface unit (RWCIU), WCC, an AN/VRC-92A SINCGARS radio, optical disc drives (ODD) and embedded data recorder.

Figure 3

RADAR SET, SEMI-TRAILER MOUNTED, AN/MPQ-53

The RS consists of a multifunction phased array radar mounted on an M-860 semi-trailer towed by an M983, heavy expanded mobility tactical truck (HEMTT) (figure 4). It is monitored and controlled by the ECS via the radar and weapon control interface unit. It performs very low- to very high-altitude surveillance, target detection, target classification, target identification, target track, missile track, missile guidance, and ECCM functions.

The radar antenna is positioned at the forward end of the shelter and is erected to a fixed 67.5 angle relative to the horizontal plane during emplacement. Integral leveling equipment on the M-860 semi-trailer permits emplacement on slopes of up to 10.

Figure 4

ELECTRIC POWER PLANT

The Electric Power Plant (EPP III) (figure 5) is the prime power source for the ECS and RS. Each EPP consists of two 150 kw, 400 Hz diesel engines that are interconnected through the power distribution unit (PDU) and are mounted on a 10-ton M977 HEMTT. Each EPP contains two interconnected 75-gallon fuel tanks and a fuel distribution assembly with grounding equipment. Each diesel engine can operate more than eight hours with a full fuel tank.

• Launcher generator set: the onboard source of LS electrical power.
• Launcher Electronics Assembly: two trailer-mounted equipment consoles that receive, decode, and execute commands of the ECS.
• Launcher Mechanics Assembly: elevates the guided missiles and contains a data link antenna mast for communications with the ECS.
• Launcher Interconnection Group: interconnects onboard LS equipment and controls the routing of electrical function lines to and from the guided missiles.

GUIDED MISSILE INTERCEPT AERIAL, MIM-104

The missile, from front to rear, consists of a radome, guidance section, warhead section, propulsion section, and control actuator section. The Patriot missile is mounted within a canister (figure 7) that functions as a shipping and storage container and as a launch tube. Guided missile canisters are stacked into groups of four per LS (PAC-2).

Figure 7

A desiccant indicator on the aft end of the canister monitors the humidity. A single umbilical cable connection interfaces the canister with the LS and provides the means for status monitoring, preheating, and launching.

The missile has four clipped-delta, movable, tail-control surfaces, and is propelled by a single-stage, all-boost solid-propellant rocket motor (figure 8). BITE checks missile readiness and provides GO or NO-GO logic for successive events in the countdown. A malfunction in any lead-in event in the missile activation and arming sequence will prevent rocket motor ignition. Any defect is automatically reported to the WCC in the ECS.

Figure 8

The standard Patriot missile (MIM-104) was the first type fielded and contained an analog fuze. This fuze was replaced by a digital version with the fielding of the MIM-104A. Both of these missiles provide excellent performance against ABTs and adequate performance against TBMs.

To counter the long-range ECM threat the MIM-104B, or standoff jammer countermeasures (SOJC) missile, was fielded in the late 1980’s. The guidance and navigation hardware was modified to allow the SOJC missile to fly a lofted trajectory to the jamming source and seek out the strongest emitter during the terminal phase of missile flight. The SOJC missile can fly three times longer than the standard missile without the uplink/downlink between the RS and missile. The SOJC missile retains the same performance against ABT and TBM as the standard missile.

The Patriot Advanced Capabilities 2 (PAC-2) missile, MIM-104C, was fielded during Operation Desert Shield and Operation Desert Storm to counter the advanced TBM threat. A new warhead and dual-mode fuze was added to the missile. The new warhead contains a more powerful explosive and larger fragments designed to place sufficient kinetic energy on the warhead section of threat TBMs to achieve a Warhead Kill. The dual-mode fuze allows the PAC-2 missile to retain ABT performance and also optimize performance against TBM. The system software based on the mission selected for the missile sets the fuze mode.

The Guidance Enhancement Missile (GEM) is an improved PAC-2 missile. A Low Noise Front End (LNFE) and improved fuze have increased lethality and expanded TBM engagement volume.

The Patriot Advanced Capability (PAC-3) missile is to be incorporated into the Patriot air defense system. It will provide defense against tactical ballistic missiles, advanced cruise missiles, and other air-breathing threats in the presence of electronic countermeasures and rough terrain.

Rather than relying on proximity detonation that can simply redirect or break up an incoming threat, the PAC-3 missile hits the target warhead to assure complete destruction. The PAC-3 missile achieves its hit-to-kill capability through the combination of an extremely accurate seeker coupled with exceptionally rapid airframe response. The missile also utilizes a lethality enhancer that is designed to increase the performance against air-breathing threats. There are 16 PAC-3 missiles per Patriot launcher (versus four PAC-2 missiles per launcher) and eight launchers per Patriot battery.