6/17/21 

Pilot/Controller Glossary 

GROUND DELAY PROGRAM (GDP)

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 A traffic 

management process administered by the ATCSCC, 
when aircraft are held on the ground. The purpose of 
the program is to support the TM mission and limit 
airborne holding. It is a flexible program and may be 
implemented in various forms depending upon the 
needs of the AT system. Ground delay programs 
provide for equitable assignment of delays to all 
system users. 

GROUND SPEED

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 The speed of an aircraft relative 

to the surface of the earth. 

GROUND STOP (GS)

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 The GS is a process that 

requires aircraft that meet a specific criteria to remain 
on the ground.  The criteria may be airport specific, 
airspace specific, or equipment specific; for example, 
all departures to San Francisco, or all departures 
entering Yorktown sector, or all Category I and II 
aircraft going to Charlotte.  GSs normally occur with 
little or no warning. 

GROUND VISIBILITY

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(See VISIBILITY.) 

GS

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(See GROUND STOP.) 

PCG G

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