POWER
CHANGES
Upon reaching cruise altitude, trim the aircraft for level
flight. Allow acceleration to cruise airspeed. Then re-
duce manifold pressure
and
RPM
to desired cruise power,
and close the cowl flaps. Lean the mixture once cruise
power
is
established. Very exacting fuel-air mixtures can
be selected by observing the exhaust gas temperature
gage
(EGT) while adjusting the mixture control vernier.
Operate
the
mixture control slowly to allow for the slight
lag in the
E
GT indicator.
CAUTION:
Do not leanthe mixture at power settings
above 75 percent rated power. In selecting
a
cruise
RPM, the engine must not be continuously operated
for cruise purposes within the range of 2100 to 2350
RPM.
Recommended cylinder head temperature for
-
continuous cruise operation
is
400~~ or less.
For best
economy lean the mixture by turning the mixture
control vernier counterclockwise until the
EGT
indicator
shows a
peak (maximurn) temperature and starts to decrease.
Then, enrich by turning the mixture control
c.locltwise until,
the temperature drops
25O~ (one mark on the gage) from
peak temperature.
For best power (maximum airspeed), lean the mixture by
turning the mixture control vernier counterclockwise to
peak temperature, and then enrich by turning clockwise un-
til the
EGT
indicator shows a drop of 100~~ (four marks on
gage) below the peak temperature.
When making power changes, it is advisable to always in-
crease RPM before increasing manifold pressure, and to
decrease manifold pressure before reducing RPM. Always
stay within the established operational limitations, and al-
ways operate controls slowly and smoothly.
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