Takeoff - Cessna 150 COMMUTER 1976 Pilot Operating Handbook

SECTION 5
PERFORMANCE
CESSNA
MODEL 150M
CRUISE CONDITIONS
Total distance
Pressure altitude
Temperature
Expected wind enroute
IANDING CONDITIONS
Field pressure altitude
Temperature
Wind component along runway
Field length
340 Nautical Miles
5500 Feet
20°C (16°C above standard)
10 Knot Headwind
2000 Feet
25°C
6 Knot Headwind
3000 Feet
TAKEOFF
The takeoff distance chart, figure 5-4, should be consulted, keeping
in mind that the distances shown are based on maximum performance
techniques. Conservative distances can be established by reading the
chart at the next higher value of altitude and temperature. For example,
in this particular sample problem, the takeoff distance information pre-
sented for a pressure altitude of 2000 feet and a temperature of 30°C
should be used and results in the following:
Ground roll
Total distance to clear a 50-foot obstacle
990 Feet
1865 Feet
A correction for the effect of wind may be made based on Note 3 of the
takeoff chart. The distance correction for a 12 knot headwind is:
12 Knots x 10%
=
13% Decrease
9 Knots
This results in the following distances, corrected for wind:
Ground roll, zero wind
Decrease in ground roll
(990 feet x 13%)
Corrected ground roll
Total distance to clear a
50-foot obstacle, zero wind
Decrease in total distance
(1865 feet x 13%)
Corrected total distance
to clear 50-foot obstacle
990
129
86f
Feet
1865
242
1623 Feet
T he se distances are well within the takeoff field length quoted earlier for
5-4
CESSNA
MODEL 150M
the sample problem.
CRU ISE
SECTION 5
PERFORMANCE
The cruising altitude and winds aloft information have been given fo r
this fl ight. However, the power setting selection for cruise must be de-
termined based on several considerations. These include the cruise per-
formance characteristics of the airplane 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 range profile chart illustrates the relationship between power
and range. Considerable fuel savings and longer range result when lower
power settings are used.
For this sample problem with a cruise altitude of 5500 feet and dis-
tance of 340 nautical miles, the range profile chart indicates that use of
a 75% power setting will necessitate a fuel stop, in view of the antiCipated
10 knot headwind component. However, selecting a 55% power setting
from the range profile chart yields a predicted range of 401 nautical miles
under zero wind conditions. The endurance profile chart, figure 5-9,
shows a corresponding 4.4 hours.
The range figure of 401 nautical miles is corrected to account for the
expected 10 knot headwind at 5500 feet.
Range, zero wind
Decrease in range due to wind
(4.4 hours x 10 knot headwind)
Corrected range
401
44
357 Nautical Miles
This indicates that the trip can be made without a fuel stop using approxi-
mately 55% 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 expected altitude and temperature conditions. The en-
gine speed chosen is 2500 RPM, which results in the following:
Power
True airspeed
Cruise fuel flow
53%
94 Knots
4.1 GPH
The power computer may be used to determine power and fuel consumption
during the flight.
5-5