F-14 Avionics

A Hughes AN/AWG-9 weapons control system is fitted to the F-14A and F-14B. The basic sys­tem has been modified several times since its introduction to the fleet, with the current ver­sion installed in late F-14As and all F-14B air­craft referred to as the AN/AWG-9D (or Block IVA) configuration. This system has the ability to detect airborne targets at ranges of 75 to 195 miles depending on the target’s cross- sectional area, and the ability to track 24 enemy targets and attack six of them simulta­neously at varied altitudes and distances. The AN/AWG-9 system weighs 1,320 pounds, occupies 28 cubic feet and uses a 36-inch diameter flat planar pulse-Doppler antenna. The antenna can search 65° to the right or left of the aircraft centerline. A modification was undertaken in 1980 to expand the radar com­puter’s memory from 32K to 64K words. The AN/AWG-9 has six basic modes of radar oper­ations: four are pulse-Doppler: two are pulse- only. The modes are;

 Pulse-Doppler Search (PDS): This mode is for basic long range detection, and is the maximum range mode of the unit. The infor­mation is displayed on the Detailed Data Display (DDD) as raw radar data in azimuth, elevation and range-rate (rate of closure). This mode does not provide absolute range to the target (only closure rate).

 Range while Search (RWS): This mode yields the greatest surveillance volume, and also returns absolute range in addition to clo­sure rate. Maximum range in this mode is slightly less than in the PDS mode. Information can be displayed on the DDD or on the Tactical Information Display (TID), although this display does not include heading, speed, or altitude information.

 Track while Scan (TWS): This mode is capable of tracking 24 targets simultaneously. The radar sweeps every two seconds, stores the targets position and vectors, and estirfiates where the target will appear next. This mode is used only for the launch of AIM-54 missiles. This mode tracks ‘virtual’ targets while it con­tinues to scan for new ones. However, if the target is maneuvering violently, it is possible for the radar to loose track on that target.

Pulse-Doppler Single Target Track (PDSTT): This mode provides the maximum range for an AIM-54 launch. This mode locks the radar’s attention onto a single target continuously illuminating that target. A Jam Angle Track (JAT) facility can be use to pro­vide range, speed, and angular information on targets being protected by ECM. In this mode, the radar can be slaved to the aircraft’s elec­tro-optical sighting unit.

Pulse Search (PS): A non-Doppler mode used for air-to-air search and ground map­ping. In this mode there is no range-rate infor­mation, only range versus azimuth.

Pulse Single Target Track (PSTT): This is another non-Doppler mode, used primary during close-in combat where Doppler infor­mation is not of much value.

Additional avionics carried aboard the F-14A and F-14B include the Fairchild AN/AWG-15F fire control set; AiResearch CP-1166A/A [CP-1166B/A in the F-14B] central air data computer; CP-1050/A computer signal data converter; AN/APX-72 IFF transponder; AN/APX-76 IFF interrogator; AN/ASA-79 multi­ple display indicator group; and the Kaiser Aerospace AN/AVG-12 vertical and heads-up display system.

The CP-1166 uses data from sensors which measure pitot and static pressures, air tem­peratures, and angle of attack to select the optimal wing sweep angle and sends com­mands to the control surfaces. It also passes to the Air Inlet Control Systems (AlCS) the information it needs to set the inlet ramps to their optimal positions.

A Harris AN/ASW-27B digital datalink pro­vides high speed data communication between the F-14 and ship-based command and control systems. This system can also be used to link to the Airborne Tactical Data Systems of Grumman E-2C Hawkeye early warning aircraft. This system can be used to pass target data back and forth between air­craft, extending the effective radar range.

All the F-14A/B’s various ECM and naviga­tion systems are tied together on a time-shar­ing basis by an AN/AYA-6 computer that is based on IBM’s 4Pi processor. The computer facilitates radar correlation, threat identifica­tion, prioritization, jammer steering, navigation functions, and the data display to the pilot and NFO. The AN/AYA-6 features IK 70-bit words of ROM and 16K 32-bit words of RAM.

Additional avionics carried aboard the F-14D include an AiResearch CP-1166B/A central air data computer; AN/ASW-27C digital data link; AN/APX-100(V) IFF/SIF transponder; AN/APX-76 IFF interrogator; JTIDS transmit­ter/receiver and processor; and the heads-up display system.