- 行业: Aviation
- Number of terms: 16387
- Number of blossaries: 0
- Company Profile:
Aviation Supplies & Academics, Inc. (ASA) develops and markets aviation supplies, software, and books for pilots, flight instructors, flight engineers, airline professionals, air traffic controllers, flight attendants, aviation technicians and enthusiasts. Established in 1947, ASA also provides ...
A form of compression-ignition reciprocating heat engine. In a diesel engine, the fuel-air mixture inside the cylinder is ignited by the heat of compression rather than by an electric spark.
The air inside the cylinder is heated as it is compressed and, when the piston is near the top of its stroke, the air is very hot. A fuel injector sprays a very fine mist of fuel into the hot air and the fuel ignites and burns. Heat added by the burning fuel expands the air and pushes the piston down.
Industry:Aviation
A form of computerized long-range navigation system that is entirely independent of outside signals. The exact latitude and longitude of the aircraft is entered into the computer before takeoff, and accelerometers and gyros produce input signals that continually update the computer as the aircraft moves through the air.
The latitude and longitude of the destination and of way points along the route are entered into the computer, and the INS works with the course deviation indicator (CDI) and the horizontal situation indicator (HSI) to direct the autopilot or the human pilot to fly the correct course to the chosen waypoint or destination.
Industry:Aviation
A form of constant displacement gear pump that uses an external-tooth drive gear that meshes with and drives an internal-tooth gear that has one more space for a tooth than there are teeth on the drive gear. Both gears turn inside a close-tolerance housing.
As the gears rotate, fluid flows between the teeth that are beginning to unmesh, and the fluid is carried around the pump as this space continues to open up. On the discharge side of the pump, the teeth begin to mesh, and as the space between the teeth becomes smaller, fluid is forced out of the pump.
Industry:Aviation
A form of constant-displacement fluid pump that uses two meshing spur gears mounted in a close-fitting housing. Fluid is taken into the housing where it fills the space between the teeth of the gears and is carried around the housing as the gears rotate. On the discharge side of the pump, the teeth of the two gears mesh, and the fluid is forced out of the pump.
Industry:Aviation
A form of contamination on aircraft spark plugs that can lead to engine failure. Silica is found in sand and dust, and if a carburetor air filter leaks and allows sand or dust to get into the engine, the silica can form a hard, glass-like deposit on the nose core insulators of the spark plugs. Silicon glaze is an insulator at low temperatures, and will not cause a spark plug to show up as bad on a tester. But when the spark plug gets hot, the silicon glaze becomes conductive, and short-circuits the high voltage to ground before it builds up high enough to jump the gap between the electrodes.
Industry:Aviation
A form of control system which uses a spring steel wire, enclosed inside a helically wound wire casing. A Bowden cable transmits both pushing and pulling motion to the device being actuated.
Bowden cable systems are often used for moving such aircraft engine controls as the throttle and the mixture control.
Industry:Aviation
A form of convergent inlet air duct used to direct air into the inlet of a gas turbine engine. The area of a convergent duct gets smaller as the air flows into the engine.
A bell-mouth inlet duct is extremely efficient, and is used where there is little ram pressure available to force the air into the engine. Bell-mouth ducts are used in engine test cells and on engines installed in helicopters.
Industry:Aviation
A form of corrosion between two surfaces which have a slight amount of relative motion between them. The protective oxide coating that forms on aluminum or magnesium alloys is rubbed away by the movement of the parts. New oxides must be continually formed to replace those that are worn away and these oxides act as an abrasive to further damage the metal.
Industry:Aviation
A form of corrosion in which an active material is used as the anode in the corrosion process to protect a less active material. The anode is sacrificed to save the cathode.
Steel parts are often plated with cadmium to sacrificially protect them from corrosion. If the coating of cadmium is scratched through to expose the steel, a corrosion cell is formed between the cadmium and the steel. The cadmium, being more anodic (more chemically active) than the steel, will be changed into a salt and it, rather than the steel, will corrode.
Industry:Aviation
A form of corrosion on metal alloys caused by a potential difference in the electrolyte, rather than by a potential difference caused by a galvanic couple within the metal. The potential difference in the electrolyte may be caused by a concentration of either oxygen or metallic ions.
Industry:Aviation
