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ADC - Air Data Computer
The air data computer receives information on air conditions surrounding the aircraft. It then converts and passes this information to the weapons system, AFDS, main computer, inertial navigator, head-up display and the crash recorder (CR). The ADC supplies information on airspeed, altitude, angle-of-attack and temperature.

ADR - Accident Data Recorder
The Crash Recording System utilises magnetic tape to record a number of data & audio streams. the system consists of the following line replaceable units,

Accident Data Recorder (ADR): The ADR houses and protects the crash data storage tape.

Data Acquisition Unit (DAU): The DAU interfaces the different types of signals from aircraft systems with the ADR. It provides power supplies for the ADR and voltage references for several transducers which are solely for the CRS operation.

Sonar Locator Beacon: The sonar locating beacon is fastened to the ADR tape housing to aid location of the ADR in the event of the aircraft crashing in the sea. If the beacon is submerged in 25 feet or more of water it will transmit an audio signal which it will continue to transmit for in excess of 240 hours.

Normal Acceleration Unit (NAU): produces a signal proportional to aircraft normal acceleration which is transmitted to the DAU for processing before being recorded on the ADR magnetic tape.

Circuit Protection Box: Interfaces the DAU with CWS drive signals to prevent certain DAU failures from placing excessive loads on the CWS circuits.

AFCS - Automatic Flying Control System
The AFCS allows the aircraft to effectively fly itself by taking pre programmed or manually input directions and converting these into electrical signals that are fed via the CSAS to the physical flying control surfaces.

AFDS - Autopilot Flight Director System

CCE - Communication Control Equipment

CSAS - Command Stability Augmentation System
The CSAS is responsible for monitoring the triplex systems are ensuring that the signals input from the independent systems are within tolerance.  The usual mechanism for such a system is to compare the results after a given number of computer processor instructions or cycles, compare the results and go with the majority unless other parameters indicate otherwise. I understand that the CSAS can resynchronise the independent systems under some circumstances.  The CSAS communicates with both the SPILS computer and the air data computer.

CVR - Cockpit Voice Recorder
The CVR is a two-track tape recorder which operates as an audio flight log for both crew members and provides a rapid data entry (RDE) facility for the insertion of data into the Main Computer.

DDVR - Displayed Data Video Recorder
The Displayed Data Video Recorder system records, on video tape, signals from selected aircraft displays, Head-up-Display Video Camera, audio signals from the Pilot and Navigator, event marker signals and internally generated control signals. The system consists of a Video Tape Recorder (VTR), a Control and Electronics Units, a Head-up-Display Video Camera and a switch mounted on Miscellaneous Switch Panel 3.

MCSS - Main Computer Sub System

The main computer is a digital mini-computer built around a Motorola 68040 microprocessor with a capacity of approximately 224K words of 16 data bits each. Post mod 14068, the memory capacity is increased to 256K. The memory is battery backed which allows ram data to be stored for 6 months with external power off. The main computer is comprised of six units, these being the Main Computer, Control Panel, 3 x Interface Units and the cockpit voice recorder.