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What Is a Magneto and Why Do Airplanes Use Them?


Small airplane flying

Magnetos are commonly found on small airplanes. They supply power to an airplane’s engines. All airplanes, of course, have at least one engine. Some of them have two or more engines. To keep these engines running, many small airplanes rely on magnetos. What are magnetos exactly, and why do airplanes use them?

Overview of Magnetos

A magneto is a type of generator that uses magnetism to produce power for an engine’s ignition system. It’s one of the oldest ignition technologies in the aerospace industry.

Magnetos provide power to the engines’ ignition system. Each engine typically has two magnetos. One of these magnetos is the primary source of ignition power. The other magneto is a backup source of ignition power. If the former magneto fails, the latter will kick in to provide power to the engine’s ignition system.

Why Airplanes Use Magnetos

Airplanes use magnetos for several reasons. For starters, magnetos aren’t dependent upon the airplane’s electrical system. They don’t rely on batteries or other sources of onboard electricity. Instead, magnetos produce their own power. If the airplane’s electrical system goes offline — meaning it completely loses power — the airplane’s engines will continue to run. The magnetos will provide power to the engines so that they will continue to run in the event of electrical failure such as this.

Magnetos are also reliable. As previously mentioned, they are one f the oldest ignition technologies in the aerospace industry. Airplanes have used magnetos for over a century. While new technologies have emerged over the years, magnetos remain a popular choice. They are time-tested and reliable, giving pilots peace of mind knowing that they will work.

Pilots may have to shut down the airplane’s electrical system intentionally. If there’s an electrical fire, for example, the pilot may shut down the airplane’s electrical system to prevent it from spreading. Assuming the airplane uses magnetos for its ignition system, the engines will continue to run.

Magnetos offer redundancy. They aren’t necessarily immune to failure. Magnetos can still fail, in which case they’ll no longer provide power to the ignition system. But most engines have two magnetos for redundancy purposes. If one of the magnetos fails, the other magneto will continue to function as intended.

In Conclusion

In piston-powered small airplanes, magnetos are commonly used for ignition purposes. Each piston engine has a pair of magnetos. The magnetos will provide power to the respective engine’s ignition system. Magnetos ensure that piston engines will continue to run even if the airplane’s electrical system goes offline.

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