Textron Aviation Cessna 172S NAV III Skyhawk SP, Information Manual

Page: 163 / 490

CESSNA SECTION 5
MODEL 172S NAV III PERFORMANCE
KAP 140 AUTOPILOT
U.S.
SAMPLE PROBLEM
(Continued)
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:
These distances are well within the available takeoff field length.
However, a correction for the effect of wind may be made based on
information presented in the note section of the takeoff chart. The
correction for a 12 knot headwind is:
This results in the following distances, corrected for wind:
(Continued Next Page)
Ground roll
1285 Feet
Total distance to clear a 50-foot obstacle 2190 Feet
12 Knots
X 10% = 13% Decrease
9 Knots
Ground roll, zero wind 1285 Feet
Decrease in ground roll (1285 feet X 13%) -167 Feet
Corrected ground roll 1118 Feet
Total distance to clear a 50-foot obstacle, zero wind 2190 Feet
Decrease in total distance (2190 feet X 13%) -285 Feet
Corrected total distance to clear 50-foot obstacle 1905 Feet
172SPHAUS-05 5-5
For
Training
Purposes
Only