How do you lean the mixture for best economy power?

Leaning the mixture for best economy power is crucial for optimizing fuel efficiency during flight. The correct method involves leaning the mixture until the engine's Exhaust Gas Temperature (EGT) reaches its peak. At this point, the fuel-to-air ratio is at its optimum for power production and efficiency.

After obtaining the peak EGT, enriching the mixture by a specific temperature margin is essential to ensure smooth engine operation. Enriching by 125°F from peak EGT is generally considered a safe practice. This allows for slightly richer conditions that help avoid engine roughness and ensures adequate cooling without sacrificing efficiency.

This method provides a good balance between fuel economy and engine performance, making it the preferred approach for pilots when adjusting the mixture for maximum efficiency during cruise flight.