SECTION 5
CESSNA
PERFORMANCE
MODEL 172S NAV III
SAMPLE PROBLEM
(Continued)
TAKEOFF CONDITIONS:
Field pressure altitude
1500 Feet
Temperature
28°C (16°C Above Standard)
Wind component
12 Knot Headwind
Field length
3500 Feet
CRUISE CONDITIONS:
Total distance
360 Nautical Miles
Pressure altitude
7500 Feet
Temperature
16°C (16°C Above Standard)
Expected wind enroute
10 Knot Headwind
LANDING CONDITIONS:
Field pressure altitude
2000 Feet
Temperature
25°C
Field length
3000 Feet
TAKEOFF
The takeoff distance chart, Figure 5-5, should be consulted, keeping
in mind that distances shown are based on the short field technique.
Conservative distances can be established by reading the chart at
the next higher value of weight, altitude and temperature. For
example, in this particular sample problem, the takeoff distance
information presented for a weight of 2550 pounds, pressure altitude
of 2000 feet and a temperature of 30°C should be used and results
in the following:
Ground roll
1285 Feet
Total distance to clear a 50-foot obstacle
2190 Feet
These distances are well within the available takeoff field length.
However, a correction for the effect of wind may be made based on
Note 3 of the takeoff chart. The correction for a 12 knot headwind is:
12 Knots X 10% = 13% Decrease
9 Knots
(Continued Next Page)
5-4 U.S.
172SPHAUS-00