Hi all,
This isn't a ROP vs LOP thread - so hoping not to start that battle. This is a "I've decided I want to run LOP what should my leaning procedures be from startup to shutdown?" question.
As background this started from reading articles by John Deakin (Numbers 8, 15, 16, 18, 19, 43, 63-66, 77 & 78 deal with engine management and running LOP), and Mike Busch (YouTube: Leaning Basics, Obsessed with EGT, Leaning The Advanced Class). Mike has a line, "I operate my engines brutally lean during ground ops and lean-of-peak exhaust gas temperatures during all phases of flight other than takeoff and initial climb" where the "brutally lean" stood out and stuck with me. What's interesting is how silent the POH is on leaning - with the exception of leaning to 1400-1450 EGT on takeoff for maximum performance.
I was taught to lean on ground, go full rich for run up and takeoff, keep full rich during climb until cruise altitude, set power & stabilize then lean, if climbing again full rich first then repeat leaning, and if decent gradually enrich on the way down. There's so much missing from this. Specifically:
After startup and during taxi what does "brutally lean" actually mean - just lean until engine roughness and then enrich until smooth?
Should run up be lean, or rich?
Or should run be full rich, and then during lean to best power (RPM rise) during?
Why not always lean to 1400-1450 on every single takeoff and climb?
When/how do you set mixture for the blue arc?
If climbing after cruise is set, full rich or keep leaned in the blue band?
Do something other than keep leaned durning descent until the GUMPS check?
After landing "brutally lean" again for taxi
I've tried to document various phases of flight to foster a discussion and procedures so they're captured on this thread. Looking forward to reading your thoughts.
-Max
As an interesting aside - I've stopped using lean finder on my EIS and am now using the big pull technique(still getting more comfortable with that). When I do I end up with EGT in the 1430-1460 range. It's almost like that number range is important or something ;).