Title: Why Do Aircraft Engines Have Two Spark Plugs Per Cylinder? | Boldmethod
Headings: Why Do Aircraft Engines Have Two Spark Plugs Per Cylinder?
Why Do Aircraft Engines Have Two Spark Plugs Per Cylinder?
1) Reliability
2) More Power
3) Even Combustion
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Spark Plug Fouling
AA1Car.com
Two Really Is Better Than One
Colin Cutler
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Content: The same thing happens. 2) More Power
There's another major benefit to having two spark plugs per engine, and that is power. When two spark plugs fire at the same time in a cylinder, you get something called a "twin flame front". That means that instead of your fuel-air mixture igniting from one point in the cylinder, it ignites from two separate locations on opposite sides of the cylinder. This is important for two reasons: 1) the fuel air mixture burns more quickly, and 2) the fuel air mixture burns more completely. And when you have both of those things happening in your cylinder, you get more power, which is something almost every pilot is looking for. 3) Even Combustion
Combustion is the last major factor in a dual spark plug configuration. When you only have one spark plug per cylinder, the fuel-air mixture burns top-down from the center, moving outward. But when you have two spark plugs on opposite sides of the cylinder, the fuel-air mixture burns from the edges of the cylinder, moving inward.