CAT III b  Operational performance Category III b. An ILS facili-ty providing operation with no decision height limit to and along the surface of the runway without reliance on external visual reference;and subsequent-ly taxiing with external visual range of not less than 50 meters (150 feet). 
CAT III c  Operational performance Category III c. An ILS facili-ty providing operation with no decision height limit to and along the surface of the runway and taxiways without reliance on external visual reference. 
CBA  Cost Benefit Analysis 
C-BAND  The frequency range between 4000 and 8000 MHz. 
CCB  (1) Converter Circuit Breaker (2) Configuration Control Board 
CCD  (1) Cursor Control Device (2) Charged Coupled Device 
CCIR  International Radio Consultative Committee 
CCITT  International Telegraph and Telephone Consultative 
CCW  Counterclockwise 
CD  Chrominance Difference 
CDG  Configuration Database Generator 
CDI  Course Deviation Indicator 
CDP  Continuous Data Program 
CDR  Critical Design Review 
CDTI  Cockpit Display of Traffic Information 
CDU  Control Display Unit 
CEPT  Conference Europeene des Postes et Telecommunications 
CF  Change Field 
CFDIU  Central Fault Display Interface Unit 
CFDS  Centralized Fault Display System 
CFIT  Controlled Flight Into Terrain 

CFMU  Central Flow Management Unit 
CFS  Cabin File Server 
CHG  Charge 
CHI  Computer Human Interface 
CHIS  Center Hydraulic Isolation System 
CHOL  Collins High Order Language 
CI  (1) Configuration Item 
(2) Cabin Interphone 
CIDIN  Common ICAO Data Interchange Network 
CIDS  Cabin Interphone Distribution System 
CIE  Commission Internationale de I Eclairage 
CIP  Capital Investment Plan 
CLB  Climb 
CLK  Clock 
Cloud  Water or ice particles having radii smaller than 0.01 
Droplets  cm 
CLR  Clear 
CMC  Central Maintenance Computer 
CMCF  Central Maintenance Computer Function 
CMCS  Central Maintenance Computer System 
CMD  Command 
CMM  (1) Component Maintenance Manual 
(2) Common Mode Monitor. A type of monitor com-