- g Acceleration due to mean Earth gravity, that is of a body in free-fall; or acceleration due to rapid change of direction of flight path.
- gallons Non-SI measure; 1 Imp gallon (UK) = 4.546 litres, 1 US gallon = 3.785 litres.
- GAZ Gosudarstvennyi Aviacionnyi Zavod (state aviation plant in the USSR; for example, GAZ-64. The numbers indicate the sequence number assigned to aviation plant).
- GFRP Glass fibre-reinforced plastics.
- 'glass cockpit' Cockpit in which dial instruments are replaced by multifunction electronic displays.
- glass fibre Spun molten glass; see GFRP.
- glideslope Element giving vertical (height) guidance in ILS.
- glove (1) Fixed portion of wing inboard of variable sweep wing; (2) additional aerofoil profile added around normal wing for test purposes.
- GmbH Gesellschaft mit beschränkter Haftpflicht (or Haftung) (German company constitution).
- GPS Global Positioning System, US military/civil satellite-based precision navaid.
- GPU Ground power unit (not part of aircraft).
- GPWS Ground-proximity warning system.
- green aircraft Aircraft flyable but unpainted, unfurnished and basically equipped.
- gross wing area See wing area.
- ground-adjustable pitch Propeller with blades that can be adjusted in pitch by an engineer on the ground. Compare flight adjustable and variable pitch.
- GS See glideslope.
- gunship Aircraft designed for battlefield attack; helicopter gunships normally with slim body carrying pilot and weapon operator only.
- GUP Gosudarstvennoye Unitarnoye Predpriyatie (Russian State Unitary Enterprise).
