Textron Cessna 172S Skyhawk SP, Information Manual

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SECTION 5
PERFORMANCE
FUEL REQUIRED
CESSNA
MODEL'172S
The total fuel requirement for th'e flight may be estimated using
the performance information in Figure 5-7 and Figure 5-8. For this
sample problem, Figure 5-7 shows that a climb from 2000 feet to
8000 feet requires 2.2 gallons of fuel. The corresponding
distance
during the climb is 15 nautical miles. These values are for a
standard temperature and are sufficiently accurate for most flight
planning purposes. However, a further correction for the effect of
temperature may be made as noted on the climb chart. The
approximate effect of a non-standard temperature is to increase the
time, fuel, and distance by 10% for each 10°C above standard
temperature, due to the lower rate ot climb. In this case, assuming a
temperature 16°C above' standard (16°C - O°C), the cor'rection
would be: . .
16°C X 10%= 16% Increase
10°C
IWith this factor included, the fuel estimate would be calculated as
follows:
Fuel'to climb, standard temperature
Increase due.to non-standard temperature
(2.2 X 16%)
Corrected fuel to climb
2.2
0.4
2.6 Gallons
Using a similar procedure for the distance to climb results in 18
nautical miles. (15 nm using chart + 2.4 nm to correct for higher
than standard temperature = 17.4 nm. Rounded up to 18 nm.)
5-6
Revision 4