Cruise Leaning - Cirrus DESIGN SR20 Information Manual

Section 4
Normal Procedures

Cruise Leaning

The engine is equipped with an altitude compensating fuel pump that
automatically provides the proper full rich mixture. Because of this, the
mixture should be set to full rich to allow the aneroid to provide auto
leaning for the engine during all flight conditions. If additional cruise
leaning beyond that provided by the aneroid is desired, be advised that
there may not be a 75° temperature rise from full rich to peak. This is
acceptable provided the airplane is at 75% power or less and engine
temperatures are within limits.
If moving the mixture control from the full rich position only
decreases the EGT from the full rich value, place the mixture
control back in the full forward position and have the fuel
system serviced.
Exhaust gas temperature (EGT) may be used as an aid for mixture
leaning in cruise flight. For "Best Power" use 75% power or less.
For "Best Economy" use 65% power or less. To adjust the mixture,
lean to establish the peak EGT as a reference point and then adjust
the mixture by the desired increment based on the following table
Mixture Description
Best Power
Best Economy
Under some conditions, engine roughness may occur while operating
at best economy. If this occurs, enrich mixture as required to smooth
engine operation. Any change in altitude or Power Lever position will
require a recheck of EGT indication.
4-20
• Caution •
Exhaust Gas Temperature
75° F Rich Of Peak EGT
50° F Lean Of Peak EGT
Cirrus Design
P/N 13999-002 Info Manual
September 2011
SR20
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