Ed Haywood
En-Route
My AFM and Lycoming Operators Manual both recommend climbing at full rich to keep the engine cool. I've always followed that advice. But looking at the engine performance graph, it's clear that results in high specific fuel consumption and less than best power.
Now that I have an engine monitor, I'm interested in operating more efficiently. Leaning to best power would be more efficient for cruise climb, both in time and fuel burn.
Cooling is the concern, of course. Each aircraft is going to behave differently, due to design differences and condition. My Decathlon has always had good airflow and cooling, especially now with a fresh engine and new baffling and oil cooler.
MP, mixture and EGT change as you climb, moving you out of the desired range. Periodically repeating the leaning process during a long climb does not seem sensible.
So I'm thinking a more effective method is to lean to best power at the start of the climb, then closely monitor CHT and adjust mixture to keep hottest cylinder at or below a desired value, say 400 F. In practice, that probably involves leaning another twist or two every thousand feet or so.
How do other folks do it?
![1723561899205.png 1723561899205.png](https://www.pilotsofamerica.com/community/data/attachments/124/124626-a022d748e93e08366522c35b0770e826.jpg)
Now that I have an engine monitor, I'm interested in operating more efficiently. Leaning to best power would be more efficient for cruise climb, both in time and fuel burn.
Cooling is the concern, of course. Each aircraft is going to behave differently, due to design differences and condition. My Decathlon has always had good airflow and cooling, especially now with a fresh engine and new baffling and oil cooler.
MP, mixture and EGT change as you climb, moving you out of the desired range. Periodically repeating the leaning process during a long climb does not seem sensible.
So I'm thinking a more effective method is to lean to best power at the start of the climb, then closely monitor CHT and adjust mixture to keep hottest cylinder at or below a desired value, say 400 F. In practice, that probably involves leaning another twist or two every thousand feet or so.
How do other folks do it?
![1723561899205.png 1723561899205.png](https://www.pilotsofamerica.com/community/data/attachments/124/124626-a022d748e93e08366522c35b0770e826.jpg)
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