Textron Cessna C172S PIM, Pilot Operating Handbook

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SECTION 5 CESSNA
PERFORMANCE MODEL 172S NAV III
GFC 700 AFCS
U.S.
SAMPLE PROBLEM
(Continued)
FUEL REQUIRED
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With an expected 10 knot head wind, the ground speed for cruise is
predicted to be:
Therefore, the time required for the cruise portion of the trip is:
The fuel required for cruise is:
A 45-minute reserve requires:
The total estimated fuel required is as follows:
Once the flight is underway, ground speed checks will provide a more
accurate basis for estimating the time enroute and the corresponding
fuel required to complete the trip with ample reserve.
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117 Knots
-10 Knots
107 Knots
342 Nautical Miles = 3.2 Hours
107 Knots
3.2 hours X 8.9 gallons/hour = 28.5 Gallons
45
X 8.9 gallons/hour = 6.7 Gallons
60
Engine start, taxi, and takeoff 1.4 Gallons
Climb 2.6 Gallons
Cruise 28.5 Gallons
Reserve 6.7 Gallons
Total fuel required 39.2 Gallons
172SPHBUS-00
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