CESSNA
MODEL 172N
SECTION 7
AIRPLANE & SYSTEMS DESCRIPTIONS
-
TANKS
STANDARD
(21.5 Gal. Each)
LONG RANGE
(27 Gal. Each)
FUEL QUANTITY DATA (U.S. GALLONS)
TOTAL
TOTAL
USABLE FUEL
UNUSABLE
ALL FLIGHT
FUEL
CONDITIONS
'.401
3
50
4
Figure 7-5. Fuel Quantity Data
TOTAL
FUEL
VOLUME
43
54
fuel from the fuel strainer and injects it into the cylinder intake ports.
Fuel system venting is essential to system operation. Blockage of the
system will result in decreasing fuel flow and eventual engine stoppage.
Venting is accomplished by an interconnecting line from the right fuel
tank to the left tank. The left fuel tank is vented overboard through
a
vent
line, equipped with a check valve, which protrudes from the bottom
surface of the left wing near the wing strut. The right fuel tank filler cap is
also vented.
Fuel quantity is measured by two float-type fuel quantity transmitters
( one in each tank) and indicated by two electrically-operated fuel quantity
indicators on the left side of the instrument panel. An empty tank is
indicated by a red line and the letter E. When an indicator shows an empty
tank, approximately
1.5
gallons remain in a standard tank, and
2
gallons
remain in a long range tank as unusuable fuel. The indicators cannot be
relied upon for accurate readings during skids, slips, or unusual attitudes.
The fuel selector valve should be in the BOTH position for takeoff,
climb, landing, and maneuvers that involve prolonged slips or skids.
Operation from either LEFT or RIGHT tank is reserved for cruising flight.
NOTE
When the fuel selector valve handle is in the BOTH
position in cruising flight, unequal fuel flow from each
tank may occur if the wings are not maintained exactly
level. Resulting wing heaviness can be alleviated gradual
ly by turning the selector valve handle to the tank in the
"heavy" wing.
NOTE
It is not practical to measure the-time required to consume
1 July 1979
7-21