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If you want to know as much as you possibly can about how airplanes work, we’ve got you covered. Here’s your complete guide on airplane magnetos.

Once you start diving into the world of aviation and learning everything that you can about airplanes, you’ll start to hear about things you might not have even known existed. Airplane magnetos are one of those things. I know that before getting into flying myself, I had never even heard about them, but now I know all there is to know about magnetos. Here’s how they work.

Airplane magnetos use magnets and coils of wire to generate the electricity necessary to ignite the fuel-air mixture in the engine’s cylinders. Their purpose is similar to the spark plugs in your car, but they generate the electricity themselves rather than relying on the main electrical system.

In this article, we'll discuss everything you need to know about airplane magnetos. We'll start with a basic definition of what they are and then move on to more specific topics like how many there are on an airplane and how they work. Finally, we'll talk about some of the things that can go wrong if there's a problem with your magnetos and what you can do to prevent that from happening.

The reason that SkyTough has been able to become one of the top aviation sites on the web is that we focus on quality content and we’ve been in your shoes before. As pilots and enthusiasts ourselves, we know what kind of questions you have and the answers that you’re looking for. So learn everything there is to know about flying as you go through the site. Let’s start with airplane magnetos.

Table of contents


What are Airplane Magnetos?

Before we can start talking about what a magneto on an airplane does and how it works, let's start from the beginning and make sure you know what they are. After all, magnetos aren't exactly common knowledge, and I'd even be willing to bet that many pilots don't know what airplane magnetos are. So without further ado, let's get into what airplane magnetos are.

In short, airplane magnetos are small devices that generate electricity to power the ignition system on an airplane. That might not sound like much, but it's actually a pretty important job. The ignition system is responsible for lighting the fuel-air mixture in the cylinders of an airplane engine, and without it, the engine wouldn't be able to start or run. Magnetos are also important because they're a backup system. If the main electrical system on an airplane fails, the magnetos can take over and keep the engine running.

To break it down even further, magnetos are basically miniature generators in and of themselves. By using magnets and coils of wire, they're able to generate the electricity needed to power the ignition system. And because they don't rely on the main electrical system (as they generate the electricity themselves), they can be a lifesaver if that system fails. So now that you have an idea of what airplane magnetos are and what they do, let's move on to what they do and how they work.

How do Airplane Magnetos Work?

As we just discussed, airplane magnetos generate electricity to power the ignition system on an airplane. But how do they do that? Well, it all has to do with magnets and coils of wire. You see, when a coil of wire is moved through a magnetic field, it generates electricity. This is the basic principle that airplane magnetos use to generate the electricity needed to power the ignition system.

The way it works is pretty simple. There's a magnet inside the magneto that's surrounded by a coil of wire. When the engine is running, the magneto spins along with the engine. This causes the coil of wire to move through the magnetic field, which in turn generates electricity. The generated electricity then flows through wires to the ignition system, powering it and allowing it to do its job.

How Many Magnetos Do Airplanes Have?

It's important to note that most airplane engines have two magnetos, not just one. This is for safety reasons. Having two magnetos means that if one fails, the other can take over and keep the engine running. It also allows for a bit of redundancy in the event that one magneto is not generating enough power.

In most airplane engines with two magnetos, there is typically one on the left and one on the right of the engine. There are some exceptions to this, but it's generally the way it's done. This not only helps to ensure that if one magneto fails, the other will be there to ignite the cylinders, but it's also useful for creating a smoother combustion process of the fuel-air mixture within the cylinder.

Now that we've discussed how airplane magnetos work, let's move on to some of the things that can go wrong if there's a problem with your magnetos.

What Happens if an Airplane Magneto Fails During Flight?

One of the most common questions I get about airplane magnetos is what happens if they fail during flight. After all, if they're such an important part of the engine's ignition system, it stands to reason that a failure could have some pretty serious consequences.

The good news is that for the most part, an airplane can continue flying even if one of the magnetos fails. However, there are a few things that you need to be aware of if this happens.

First, if one magneto fails, the engine will run a bit rougher. This is because the ignition system will only be receiving power from one source instead of two. Additionally, the engine will only be firing on half of its cylinders. This can lead to a loss of power and a decrease in performance.

In most cases, however, the engine will continue running and the airplane will be able to safely land at its destination. It's important to note that if both magnetos fail, the engine will shut down and the airplane will lose all power. This is why it's so important to have two magnetos in the first place - to provide a backup in case one fails.

So now that you know what can happen if an airplane magneto fails, let's talk about how often you should be inspecting them.

How Often Should You Inspect the Magnetos on Your Airplane?

The magnetos on your airplane should be inspected regularly. Most mechanics recommend doing a thorough inspection at least once a year. However, if you fly frequently or put a lot of hours on your airplane, you may want to inspect the magnetos more often.

During an inspection, the mechanic will typically perform a visual inspection of the magnetos as well as an operational check. The visual inspection will look for any obvious signs of damage or wear. The operational check will involve actually starting the engine and checking to see if the magnetos are working properly.

If everything looks good during the inspection, then you're all set! However, if there are any issues with the magnetos, they will need to be repaired or replaced before you can fly again.

Airplane Magneto Maintenance

Now that we've talked about how airplane magnetos work and how often you should inspect them, let's discuss some of the maintenance that is involved in keeping them in good working condition.

As with any other part of your airplane, the magnetos will need to be cleaned and lubricated on a regular basis. This will help to prevent any corrosion or buildup of dirt and debris.

Additionally, the spark plugs will need to be replaced periodically. The frequency with which they need to be replaced will depend on how often you fly as well as the type of engine that you have. However, most mechanics recommend replacing them every 50-100 hours of flight time.

Finally, it's important to keep an eye on the wiring that connects the magnetos to the rest of the ignition system. Over time, this wiring can become damaged or corroded. If this happens, it can lead to problems with the magnetos themselves. Therefore, it's important to inspect the wiring regularly and repair or replace it as needed.

By following these simple tips, you can help to ensure that your airplane's magnetos will always be in good working condition. And that means you can rest assured knowing that your engine will always have a reliable source of ignition power.

And that's everything you need to know about airplane magnetos! I hope this article has helped you to better understand how they work and why they're so important. If you have any questions, feel free to leave a comment below and I'll do my best to answer them. Thanks for reading!