BMV  Brake Metering Valve 
BNR  Binary 
BOM  Bill of Material 
BOP  Bit Oriented Protocol 
Boresighting  The process of aligning a directional antenna system. 
BP  (1) BITE Processor 
(2) Bottom Plug 
BPCU  Bus Power Control Unit 
BPSK  Binary Phase Shift Keying 
BRG  Bearing 
BRT  Brightness 
BSCU  Brake System Control Unit 
BSU  (1) Bypass Switch Unit 
(2) Beam Steering Unit 
BTB  Bus Tie Breaker 
BTMU  Brake Temperature Monitor Unit 
BU  Backup 
BusAv  Business Aviation 
Byte  A grouping of eight bits. 
C 
CAA  Civil Aviation Authority. A regulatory agency in the 
United Kingdom. 
CAAC  Civil Aviation Administration of China 
CAASD  Center for Advanced Aviation System 
Development(The Mitre Corp.) 
C/A Code  (1) GPS Course Acquisition Code 
(2) Course-Acquisition Code 
CAC  Caution Advisory Computer 
CACP  Cabin Area Control Panel 

CAD  Computer Aided Design 
CAE  Component Application Engineer 
CAGE  Commercial Avionics GPS Engine 
CAH  Cabin Attendant Handsets 
CAI  Caution Annunciator Indicator 
Calibrated Airspeed  Corrected for instrument errors and errors due to position or location of the pressure source. At stan dard sea level conditions,CAS is equal to true air speed (TAS). 
CALSEL  A variation of the SELCAL system in which the SEL-CAL signal is combined with a special gating tone to produce an automatic function by the receiver. This system is only a proposal and not yet implemented. 
CAM  Computer Aided Manufacturing 
CAMI  FAA Civil Aeromedical Institute 
CAPT  Captain 
Carrier  An ac signal that can be modulated by changing the amplitude,frequency or pulse of the signal. 
CAS  (1) Computed Airspeed (2) Collision Avoidance System 
CAT  Computer Aided Testing 
CAT I  Operational performance Category I. An ILS facility providing operation down to a 60-meter (200 feet) decision height and with runway visual range not less than 800 meters (2600 feet) and a high probability of approach success. 
CAT II  Operational performance Category II. An ILS facility providing operation down to a 30-meter (100 feet) decision height and with runway visual range not less than 400 meters (1200 feet) and a high probability of approach success.