Reference

Magnetos

• How do I install an aircraft magneto?

  Aircraft magneto installation is a straightforward but delicate process. Improper installation can lead to damage of the magneto. Installation should be handled according to the manufacturer’s specifications and procedures.

• If one aircraft magneto fails do I have to service both magnetos?

  It is not required to service both aircraft magnetos at the same time but it is a good idea to keep the pair of magnetos on the same maintenance schedule to avoid additional down time in the future.

• Is the aircraft magneto connected to the rest of the electrical system?

  No, the aircraft magneto ignition system is self-contained and independent from the aircraft electrical system. In the event of an electrical failure, the mechanical aircraft magneto will continue to provide spark to the engine. 

• What is the difference between a pressurized and non-pressurized aircraft magneto?

  Pressurized aircraft magnetos are usually found in turbocharged engines. Air is diverted from the turbocharging system and sent through a line to a fitting installed in the aircraft magneto. The aircraft magneto is also fitted with an opening at the bottom of the housing to allow a small air leak. This opening insures a constant flow of air through the aircraft magneto to avoid the internal air from becoming ionized.

• What powers an aircraft magneto?

  The aircraft magneto is a self-contained generator that consists of a magnet spinning in close proximity to a high-output coil. As the magnet spins, it creates a magnetic field. Fluctuations in that field create an electrical current. Eventually, the current generated by magnetic flux undergoes a voltage spike that is strong enough to fire a spark plug.

• Why are there two aircraft magnetos?

  The dual arrangement of aircraft magnetos produces a smoother and more complete combustion of the fuel mixture. It also provides for ignition redundancy, so that the engine will continue to run in the event that one magneto malfunctions.

• Why do aircraft need magnetos?

  In aircraft engines, it is important to maintain an ignition system independent of the eletrical system, so that the engine will continue to run in the event of alternator or battery malfunction. Additionally, aircraft magnetos provide a compact and reliable means for igniting the spark plugs.