-  xxix  - 
   
CORREL 
CORRELation 
   
CPA/TCPA  The distance to the Closest Point of Approach    and Time to the Closest 
Point of Approach.    Limits are set by the operator and are related to 
own ship. 
   
CTW 
Course Through Water 
The direction of the ship's movement through the water 
D 
DRIFT 
The current velocity for manual correction or the current speed on the 
horizontal axis of the 2-axis log is displayed. 
E 
EBL 
Electronic Bearing Line 
An electronic bearing line originated from own ship’s position. 
   
ENH 
Enhance 
   
ETA 
Estimated Time of Arrival 
G 
Ground 
stabilization   
A display mode in which speed and course information are referred to 
the ground, using ground track input data. 
H 
HDG 
Heading 
The horizontal direction that the bow of a ship is pointing at any instant, 
expressed in angular units from a reference direction . 
   
HL  Heading line 
A graphic line on a radar presentation drawn from the consistent 
common reference point to the bearing scale to indicate the heading of 
the ship   
   
HSC  Vessels which comply with the definition in SOLAS for high speed 
craft 
   
H up 
Head up 
Own ship’s heading line is always pointed to the top center of the radar 
display. 
I 
IMO 
International Maritime Organization 
   
Interswitch Unit 
A device to switch over two or more radar display units and two or 
more scanners. 
   
IR 
radar Interference Rejecter