Gas producer--  the compressor in a free-power turbine engine.   Gas turbine engine --  aircraft power plant that is adaptable for both airplanes and helicopters.  
 

Gerotor pump --  modified gear-type pump with two moving parts, an inner toothed element and an outer toothed element. The inner one has one less tooth than the outer.   Glow plug --  device that consists of a heating element in a short conventional-looking spark plug.   Ground angle --  angle between the wing chord and the horizontal plane when the airplane is at rest on the ground.   Heat exchanger --  fuel-oil cooler, to help cool the oil. The exchanger is a cylindrical oil chamber surrounded by a jacket through which the fuel passes. Heat from the oil is transferred to the fuel by conduction.   Hot start --  overtemperature during starting.   Hung start --  failure to reach normal idling RPM during starting.   Igniter plugs--  spark plugs which function only during starting and cut out of the circuit as soon as combustion is self-supporting.   Imbalance --  uneven distribution of weight resulting in rotating parts being out of balance. Measured in inch-grams or inch-ounces.   Impeller rotor --  rotor in a compressor that revolves at high speed, drawing air into the blades.   Induced angle of attack --  that part of any given angle of attack in excess of the effective angle of attack.   Induced drag --  the part of the total dragon an airplane induced by the airflow about the lifting surfaces.  
 

Inlet guide vanes --  devices positioned by the inlet guide vane actuator pilot valve. They are located in front of the first compressor rotor, and they control the angle of incidence of the inlet air, thus ensuring a compressor surge margin.   Inlet housing assembly --  forward structural support of the engine. 
 

 
 
飛機(jī)發(fā)動(dòng)機(jī)術(shù)語英文解釋（J-N）
 

Jam acceleration --  rapid movement of the power lever, calling for maximum rate of rotor-speed increase.   Jetcal analyzer --  device used to check the exhaust gas temperature during periodic maintenance inspections or when abnormally high or low temperatures are noted.   Jet propulsion --  propulsion of a body by means of a jet or stream of gas, obtaining all or most if its thrust by reaction to the ejection of the combustion products (gas).   Jet silencer --  a device used to reduce and change the lower-frequency sound waves emitting from the engine's exhaust nozzle, and thus reducing the noise factor.   Joule --  unit of energy or work used in rating gas turbine ignition systems. A joule is equal to the amount of energy expended in one second by an electric current of one ampere through a resistance of one ohm.   Labyrinth seal --  device for preventing leakage of gas on the gas generator shaft in a turbine. A labyrinth consists of a series of projections on the rotating element running in close contact with grooves on the stationary element.   Maintenance allocation chart --  chart in a -20 TM that assigns maintenance tasks to the lowest level capable of doing them, based on experience, skills, tools, and time available.