How the engine works, in 3D
Watch a see-through cylinder go through intake, compression, power and exhaust, with magneto-fired spark plugs.
Try it: press Step to move one stroke at a time. Watch the valves open, the spark fire and the piston turn the crankshaft that spins the propeller.
Loading 3D lab…
Crank angle0°720° = one full cycle
Simplified single cylinderWhat your engine controls do
- Throttle: controls how much fuel-air mixture reaches the cylinders, and so power (RPM or manifold pressure).
- Mixture: sets the fuel-to-air ratio. Air gets thinner as you climb, so you lean the mixture. Full rich for takeoff at most airports (follow the POH, especially at high-elevation airports).
- Carburetor heat: sends warm air to the carburetor to prevent or melt carburetor ice. The first sign of carb ice with a fixed-pitch prop is a drop in RPM.
- Magnetos: two independent magnetos fire two spark plugs per cylinder. They run off the engine's rotation, not the battery, so the engine keeps running if the electrical system fails. That's what the mag check before takeoff tests.
Most training airplanes have horizontally opposed, air-cooled engines with four or six cylinders. This lab shows one cylinder upright for clarity. Learn your engine's limits and procedures from the POH.
Sources: PHAK Chapter 7 (Aircraft Systems).
Check yourself
Use it with
Aircraft Systems2 min read
Prepare for: Preflight InspectionLesson Prep
Prepare for: Engine Start and TaxiLesson Prep
Prepare for: Before-Takeoff Check (Run-Up)Lesson Prep
Prepare for: Systems and Equipment MalfunctionsLesson Prep
Prepare for: Engine Failure and Emergency ApproachLesson Prep
Prepare for: High-Altitude Operations: Oxygen and PressurizationLesson Prep