Ignition and Electrical

Since turbine engine ignition systems normally operate only during the engine-starting cycle, they are generally more reliable and require less maintenance than reciprocating engine ignition systems. Unlike reciprocating engine ignition systems, turbine engine ignition systems do not require ignition timing to occur at a precise point in the engine operating cycle. The system is used … Read more

Aircraft powerplant electrical systems require properly installed electrical components to ensure safe, reliable, and efficient operation. Correct management of electrical loads, effective circuit protection, and the proper selection of switches and relays help prevent overloads, protect electrical wiring and equipment, and maintain dependable system performance. This section provides general procedures and safety precautions for the … Read more

Maintenance of a typical turbine engine ignition system consists primarily of inspection, testing, troubleshooting, removal, and installation of ignition system components. Inspection Inspection of the ignition system normally includes the following: Check System Operation The igniter can be checked by listening for a snapping noise as the engine begins to turn, driven by the starter. … Read more

Reliable electrical connections are essential for the safe operation of aircraft powerplant electrical systems. Proper installation of terminal lugs on terminal blocks ensures secure mechanical attachment, minimizes electrical resistance, and helps prevent loosening caused by engine vibration. The following guidance explains recommended practices for connecting terminal lugs to terminal blocks using the correct hardware arrangement … Read more

The function of a spark plug in an ignition system is to conduct a short impulse of high-voltage current through the combustion chamber wall. Within the combustion chamber, the spark plug provides an air gap across which the electrical impulse produces a spark to ignite the air-fuel mixture. Although aircraft spark plugs are relatively simple … Read more

Accurate magneto-to-engine timing is essential for proper ignition system operation and engine performance. Several timing references and tools are used to establish the correct crankshaft position and determine the exact point at which the magneto breaker points open. These include built-in engine timing marks, timing discs, piston position indicators, and timing lights. Built-In Engine Timing … Read more

Broken copper wires can be temporarily repaired using crimped splices, terminal lugs with the tongue removed, or by soldering and potting the broken conductors. These repairs are applicable to copper wire. Damaged aluminum wire must not be repaired by temporary splicing. These methods are intended for temporary emergency repairs only and should be replaced with … Read more

A FADEC is a solid-state digital electronic ignition and electronic sequential port fuel injection system with only one moving part that consists of the opening and closing of the fuel injector. FADEC continuously monitors and controls ignition timing, fuel delivery, fuel-air mixture, and fuel injection as an integrated engine control system. FADEC monitors engine operating … Read more

Connectors and conduit are important components of aircraft engine ignition and electrical system installations. Connectors provide secure electrical connections while allowing circuits and equipment to be disconnected for maintenance, and conduit protects wiring from mechanical damage. Proper selection, installation, and handling help maintain reliable electrical operation in the demanding engine environment. Connectors Connectors (plugs and … Read more