Cessna 152 1979, Pilot Operating Handbook

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CESSNA SECTION 5
MODEL 152 PERFORMANCE
1 July 1978 5- 5
CRUISE
The cruising altitude should be selected based on a consideration of trip length, winds aloft,
and the airplane's performance. A typical cruising altitude and the expected wind enroute have
been given for this sample problem. However, the power setting selection for cruise must be
determined based on several considerations. These include the cruise performance
characteristics presented in figure 5-7, the range profile chart presented in figure 5-8. and the
endurance profile chart presented in figure 5-9.
The relationship between power and range is illustrated by the range profile chart.
Considerable fuel savings and longer range result when lower power settings are used.
The range profile chart indicates that use of 65% power at 5500 feet yields a predicted range
of 375 nautical miles under no wind conditions. The endurance profile chart, figure 5-9, shows
a corresponding 3.9 hours.
The range figure of 375 nautical miles is corrected to account for the expected 10 knot
headwind at 5500 feet.
Range, zero wind 375
Decrease in range due to wind
(3.9 hours x 10 knot headwind) 39
Corrected range 336 Nautical Miles
This indicates that the trip can be made without a fuel stop using approximately 65 % power.
The cruise performance chart, figure 5-7, is entered at 6000 feet altitude and 20°'C above
standard temperature. These values most nearly correspond to the planned altitude and
expected temperature conditions. The engine speed chosen is 2400 RPM, which results in the
following:
Power
640%
True airspeed 99 Knots
Cruise fuel flow 5.2 GPH
The power computer may be used to determine power and fuel consumption more accurately
during the flight.
FUEL REQUIRED
The total fuel requirement for the flight may be estimated using the performance information in
figures 5-6 and 5-7. For this sample problem, figure 5-6 shows that a climb from 2000 feet to