GATE HOLD PROCEDURES -- GROUND VISIBILITY
GATE HOLD PROCEDURES- Procedures at selected airports
to hold aircraft at the gate or other ground location
whenever departure delays exceed or are anticipated
to exceed 15 minutes. The sequence for departure
will be maintained in accordance with initial
call-up unless modified by flow control restrictions.
Pilots should monitor the ground control/clearance
delivery frequency for engine start/taxi advisories
or new proposed start/taxi time if the delay changes.
(See FLOW CONTROL.)
GCA- (See GROUND CONTROLLED APPROACH.)
GENERAL AVIATION- That portion of civil aviation
which encompasses all facets of aviation except
air carriers holding a certificate of public convenience
and necessity from the Civil Aeronautics Board
and large aircraft commercial operators.
(See ICAO term GENERAL AVIATION.)
GENERAL AVIATION [ICAO]- All civil aviation operations
other than scheduled air services and nonscheduled
air transport operations for remuneration or hire.
GEO MAP- The digitized map markings associated
with the ASR-9 Radar System.
GLIDEPATH- (See GLIDESLOPE.)
GLIDEPATH INTERCEPT ALTITUDE- (See GLIDESLOPE
GLIDESLOPE- Provides vertical guidance for aircraft
during approach and landing. The glideslope/glidepath
is based on the following:
a. Electronic components emitting signals which
provide vertical guidance by reference to airborne
instruments during instrument approaches such
as ILS/MLS, or
b. Visual ground aids, such as VASI, which provide
vertical guidance for a VFR approach or for
the visual portion of an instrument approach
c. PAR. Used by ATC to inform an aircraft making
a PAR approach of its vertical position (elevation)
relative to the descent profile.
(See ICAO term GLIDEPATH.)
GLIDEPATH [ICAO]- A descent profile determined
for vertical guidance during a final approach.
GLIDESLOPE INTERCEPT ALTITUDE- The minimum altitude
to intercept the glideslope/path on a precision
approach. The intersection of the published intercept
altitude with the glideslope/path, designated
on Government charts by the lightning bolt symbol,
is the precision FAF; however, when ATC directs
a lower altitude, the resultant lower intercept
position is then the FAF.
(See FINAL APPROACH FIX.)
(See SEGMENTS OF AN INSTRUMENT APPROACH PROCEDURE.)
GLOBAL POSITIONING SYSTEM (GPS)- A space-base
radio positioning, navigation, and time-transfer
system. The system provides highly accurate position
and velocity information, and precise time, on
a continuous global basis, to an unlimited number
of properly equipped users. The system is unaffected
by weather, and provides a worldwide common grid
reference system. The GPS concept is predicated
upon accurate and continuous knowledge of the
spatial position of each satellite in the system
with respect to time and distance from a transmitting
satellite to the user. The GPS receiver automatically
selects appropriate signals from the satellites
in view and translates these into three-dimensional
position, velocity, and time. System accuracy
for civil users is normally 100 meters horizontally.
GO AHEAD- Proceed with your message. Not to be
used for any other purpose.
GO AROUND- Instructions for a pilot to abandon
his approach to landing. Additional instructions
may follow. Unless otherwise advised by ATC, a
VFR aircraft or an aircraft conducting visual
approach should overfly the runway while climbing
to traffic pattern altitude and enter the traffic
pattern via the crosswind leg. A pilot on an IFR
flight plan making an instrument approach should
execute the published missed approach procedure
or proceed as instructed by ATC; e.g., "Go
around" (additional instructions if required).
(See LOW APPROACH.)
(See MISSED APPROACH.)
GPS- (See Global Positioning System.)
GROUND CLUTTER- A pattern produced on the radar
scope by ground returns which may degrade other
radar returns in the affected area. The effect
of ground clutter is minimized by the use of moving
target indicator (MTI) circuits in the radar equipment
resulting in a radar presentation which displays
only targets which are in motion.
GROUND COMMUNICATION OUTLET (GCO)- An unstaffed,
remotely controlled, ground/ground communications
facility. Pilots at uncontrolled airports may
contact ATC and FSS via VHF to a telephone connection
to obtain an instrument clearance or close a VFR
or IFR flight plan. They may also get an updated
weather briefing prior to take-off. Pilots will
use four "key clicks" on the VHF radio
to contact the appropriate ATC facility or six
"key clicks " to contact the FSS. The
GCO system is intended to be used only on the
GROUND CONTROLLED APPROACH- A radar approach system
operated from the ground by air traffic control
personnel transmitting instructions to the pilot
by radio. The approach may be conducted with surveillance
radar (ASR) only or with both surveillance and
precision approach radar (PAR). Usage of the term
"GCA" by pilots is discouraged except
when referring to a GCA facility. Pilots should
specifically request a "PAR" approach
when a precision radar approach is desired or
request an "ASR" or "surveillance"
approach when a nonprecision radar approach is
(See RADAR APPROACH.)
GROUND DELAY- The amount of delay attributed to
ATC, encountered prior to departure, usually associated
with a CDT program.
GROUND SPEED- The speed of an aircraft relative
to the surface of the earth.
GROUND STOP- Normally, the last initiative to
be utilized; this method mandates that the terminal
facility will not allow any departures to enter
the ARTCC airspace until further notified.
GROUND VISIBILITY- (See VISIBILITY.)