Piper Malibu PA-46-310P Pilot Operating Handbook page 130

SECTION 4
NORMAL PROCEDURES
PIPER AIRCRAFT CORPORATION
PA-46-310P, MALIBU
NOTE
Maximum continuous T.I.T. is 1750°F.
Temporary operation up to 1800°F is
permitted in order to define peak T.I.T. In no
case should the aircraft be operated more than
30 seconds with a T.I.T. in excess of 1750°F.
The cruising speed is determined by many factors, including power
setting, altitude, temperature, loading and equipment installed in the
airplane.
The engine has been designed to attain the maximum possible fuel
efficiency while maintaining the desired cruise power. This requires
operating on the lean side of peak T.l.T. Although this procedure is different
from conventional leani~g procedures, it will produce the maximum fuel
efficiency and will actually produce cooler engine temperatures than
conventional peak T.I.T. or rich of peak operation. The cruise mixture
setting is 50° lean of peak T.I.T.
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After leveling off at cruise altitude, set the RPM and manifold pressure
for the desired cruise power in accordance with the power setting table.
Using the fuel flow indicator as a reference, lean the mixture to
I
approximately 4 gallons per hour above the cruise fuel flow value listed in
V
the power setting table. From this point on use the T.I. T. gage as a reference.
Slowly lean to peak T.I.T. and continue leaning until the T.I.T. has fallen
50°F.
The manifold pressure may increase above cruise setting as the mixture
is leaned toward peak T. I. T., when operating at or near the altitude limits of
the lower power/ rpm settings, or at or near 25,000 feet pressure altitude, if
the ambient temperature is above standard for either condition. Should this
occur, select a power setting from the power table (fig. 5-21) requiring a
higher rpm or lower manifold pressure. Mainfold pressure fluctuations
during leaning may be prevented by reducing cruise altitude.
NOTE
The induction system must be properly
maintained to obtain certified engine
performance. Small leaks will significantly
reduce altitude capability.
REPORT: VB-1200
4-26
ISSUED: JANUARY 11, 1984
REVISED: APRIL 1, 1987
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