CSDS  Cargo Smoke Detector System 
CSEU  Control Systems Electronics Unit 
CSMM  Crash Survivable Memory Modules 
CSMU  Cabin System Management Unit 
C/SOIT  Communications/Surveillance Operational 
Implementation Team 
CSU  Configuration Strapping Unit 
CTA  (1) Controlled Time of Arrival 
(2) Common Traffic Advisory 
CTAI  Cowl Thermal Anti-Icing 
CTAS  Center Tracon Automation System 
CTC  Cabin Temperature Controller 
CTL  Control 
CTMO  Centralized Air Traffic Flow Management Organization 
CTOL  Conventional Take Off and Landing 
CTR  Control zone 
CTRD  Configuration Test Requirements Document 
CTS  Clear To Send 
CU  Control Unit 
CVR  Cockpit Voice Recorder 
CVRCP  Cockpit Voice Recorder Control Panel 
CW  (1) Continuous Wave. A continuous train of identical 
oscillations. 
(2) Clockwise (cw) 
C & W  Control and Warning 
CWI  Continuous Wave Interference 
CWP  (1) Controlled Working Position 
(2) Controller Working Position 
CWS  Control Wheel Steering 

D

DA  Descent Advisor 
D/A  Digital-to-Analog 
DABS  Discrete Addressable Beacon System 
DADC  Digital Air Data Computer 
DADS  Digital Air Data System 
DAL  Delta Air Lines 
DARC  Direct Access Radar Channel. An independent backup 
to main ATC computers. 
DARP  Dynamic Aircraft Route Planning 
DARPA  Defense Advanced Research Projects Agency 
Data Link  A system that allows exchange of digital data over an 
rf link. ATCSS is a data link system used by the air 
traffic control system. ACARS is a data link system 
used by airline command,control and management 
system,using vhf communication frequencies. 
D-ATIS  Digital Automatic Terminal Information System