曝光台 注意防骗
网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者
grit blasting. Another name for abrasive blasting. See abrasive blasting.
grommet (protective device). A rubber or plastic ring used to cover the edges of a hole in thin sheet metal.
When wires or tubes pass through a hole in a piece of thin sheet metal, the edges of the hole should be
protected with a grommet so the sharp metal cannot damage them.
gross thrust (turbine engine specification). The thrust produced by a turbojet or turbofan engine when the
engine is static, or not moving. The air is considered to have no inlet velocity, and the velocity of the gas
leaving the engine is considered to be the acceleration factor. Gross thrust includes the thrust generated by
the momentum of the outgoing gases and the thrust resulting from the difference between static pressure at
the nozzle and ambient pressure.
gross weight (aircraft specification). The loaded weight of an aircraft. Gross weight includes the total
weight of the aircraft, the weight of the fuel and oil, and the weight of all the load it is carrying.
ground (electrical reference point). A reference point in an electrical system from which all voltage
measurements are made. In an aircraft electrical system, the negative terminal of the battery is normally
connected to the aircraft structure, and this acts as the ground.
In household and industrial electrical power systems, one lead connects to the earth, which serves
as the ground. In the United Kingdom ground is spoken of as “earth.”
ground-adjustable propeller. A type of aircraft propeller whose blade pitch angle can be adjusted when
the engine is not running. The adjustment requires loosening the blades in the hub.
ground-boosted engine (reciprocating engines). An aircraft reciprocating engine with a built-in
supercharger that boosts the sea-level rated horsepower of the engine.
ground clutter (radar reception). A pattern produced on the radarscope by ground returns which may
degrade other radar returns in the affected area.
ground controlled approach. See GCA.
Printed from Summit Aviation's Computerized Aviation Reference Library, 2/7/2007
Page 284
ground crew (aircraft operation). The group of people who service and maintain an aircraft when it is on
the ground. The ground crew prepares the aircraft for flight and services it after its return from flight.
ground delay (air traffic control). The amount of delay attributed to ATC, encountered prior to departure,
usually associated with a controlled departure time (CDT) program.
grounded-base amplifier (transistor amplifier). See common-base amplifier.
grounded-collector amplifier (transistor amplifier). See common-collector amplifier.
grounded-emitter amplifier (transistor amplifier). See common-emitter amplifier.
ground effect (aerodynamics). An increase in lift of an aerodynamic flying machine (airplane or
helicopter) flying very near the ground. This additional lift is caused by an effective increase in angle of
attack without the accompanying increase in induced drag and is caused by the deflection of the
downwashed air. Ground effect disappears when the flying machine is about a half wing span or half rotor
span above the surface.
ground fog (meteorology). A fog that conceals less than six tenths of the sky and is not a part of the cloud
base.
ground idle (gas turbine engine operating specification). The engine speed normally used for operating a
gas turbine engine on the ground so it produces the minimum amount of thrust. Ground idle is normally in
the range of 60% to 70% of the maximum RPM.
ground loop (aircraft operation). A sharp, uncontrolled change in direction of an airplane on the ground.
Tail wheel-type airplanes are highly subject to ground looping because their center of gravity is behind the
point at which the main wheels contact the ground.
ground loop (electrical condition). A condition of unwanted current flow in a circuit that uses shielded
wire (wire encased in a braided metal cover). The purpose of the shielding is to intercept and carry to
ground electrical energy radiated from the wires inside the shielding.
If the shielding is connected to the ground at more than one point, it is possible for current to flow
out one connection, through the ground, and back into the shielding through another connection. This
current flowing in the shielding can interfere with delicate electrical signals in the shielded wire. To prevent
ground loops, the shielding is grounded at one point only.
ground plane (radio antenna component). A reflector used with a vertically polarized,
quarter-wavelength radio antenna. Horizontal arms or a flat metal plane that sticks out at least a quarter
wavelength from the base of the antenna reflects the signal.
ground potential (electrical circuit condition). An electrical condition in which there is no voltage
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：
航空术语词典Dictionary of Aeronautical Terms 中(60)
