Here’s another view of a reciprocating engine, which most small aircraft contain. They’re called that because of the pistons moving back and forth, or reciprocating, inside the cylinders. These engines burn a mixture of fuel and air in the cylinders using 4 strokes (Intake, Compression, Power, Exhaust). Piston engines in most aircraft have a dual ignition system. This means each cylinder has 2 spark plugs that fire simultaneously, providing redundancy and more efficient burning inside the cylind