CIRRUS DESIGN 2220, Pilot Operating Handbook

Page: 239 / 334

C
IRRUS
D
ESIGN
S
ECTION
7: A
IRPLANE AND
S
YSTEMS
SR20 M
IXTURE
M
ANAGEMENT
P/N 11934-005 7-45
Mixture Management
The mixture control needs to be carefully monitored and managed during
all phases of flight to avoid damage to the engine or a possible loss of power.
After engine start, and during taxiing operations, lean the mixture until
maximum engine RPM is attained to prevent possible spark plug fouling
and ensure smooth engine operation.
Takeoff and climb fuel flows need to be set appropriately. Maintain mixture
control in the FULL RICH position for rated take-off, climb and maximum
cruise powers (above approximately 75%). During take-off from a high
elevation airport or during climb, roughness or loss of power can occur
from over-richness. In such a case, adjust the mixture control only enough
for smooth operation - not for economy. Monitor instruments for
temperature rise.
During climb, it is necessary to lean the mixture to ensure engine smooth-
ness and optimal power. Rough operation due to over-rich fuel/air mixture
is most likely to be encountered at altitudes above 5,000 feet (1524 meters).
Follow the placarded MAX power fuel flow leaning schedule and informa-
tion published in this POH. Refer to
Section 4: Normal Procedures . The top
of the green arc on the display may be used as a reference. EGT's should
generally be at least 1300 °F at full power. If CHTs or oil temps become
higher than desired, using a slightly richer-than-placarded fuel flow will aid
in engine cooling.
During cruise flight, the throttle should be set for 85% power or less when
operating the engine at best power and 75% power at best economy mixture
settings. During best power operations the mixture should be set for 100 °F
rich of peak EGT. During best economy operations the mixture should be
set to 50 °F lean of peak EGT. Alternatively, the mixture can be set to the
cyan target FF mark that is displayed on the FF gauge.
If a cruise power descent is used, it is necessary to richen the mixture to
maintain EGT's at approximately 1300 - 1500 °F during descent. If a
reduced power descent is used, it is still necessary to richen the mixture to
prevent loss of power or an overly lean condition when power is added.
During approach and landing, the mixture should be set to FULL RICH, or
the position that will result in obtaining the placarded full throttle fuel
flows if the throttle were advanced to wide open.
Reissue A