XtremeAIR XA42, Руководство по эксплуатации самолета

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Airplane Flight Manual XA42
AFM-XA42-0040-002-A.01
Page date : Page 8
24.01.2011 Chapter 07
7.11 FUEL SYSTEM
7.11.1 GENERAL
The fuel system consists of two separate wing tanks and one acro tank. For utility flights all the tanks
may be used. During acrobatic flights the wing tanks must be empty. The total volume of all three
tanks is 275 L / 72.5 US gal.
The acro tank which must be used for take-off, landing and acrobatics has a capacity of 65 L / 17.1
US gal. The fuel selector valve is labeled “ACRO“ accordingly. Fuel is picked up through a flop tube
from an 11 L / 2.9 US gal header tank located underneath the acro tank. This header tank’s capacity
adds to the acro tank, meaning the usable fuel is in fact 76 L / 20.0 US gal, but due to the fact that
the fuel probe does no extend in the header tank, the header tank is excluded from the fuel capacity
indication and therefore also flights must be planned without these 11 L / 2.9 US gal. The header tank
is gravity fed by the acro tank via a ¾’’ tube. During inverted flight, the header tank is not refilled,
which limits the time of inverted flight to the use of 11 L, app. 3 min at full power. In case the
inverted flight is extended too long and the engine quits, it takes app. 10 sec. to refill the header tank
enough for the engine to restart. Therefore it is recommended not to perform inverted flight for more
than 2 min uninterruptedly. Due to the flop tube in the header tank, the acro tank can be flown down
to 0.5 L even at high yaw and bank angles. The acro tank is mounted in and supported by the tank
compartment of the fuselage.
The two wing tanks are located in the inner 3 compartments (wing root) in front of the main spar of
both sides of the wing. Each can fit 105 L / 27.7 US gal of fuel and can be flown down to 0.5 L in
straight and level flight. The total volume of the wing tanks is 210 L / 54,4 US gal. With 5 ° yaw ½
ball out and corresponding bank 0,5 L / 0.13 US gal remain non usable.
The tanks all have their own filler cap with a diameter of 46 mm each.
Venting of the wing tanks is accomplished through a system that connects the wing tank vent hoses
to the top of the acro tank. Then the acro tank is vented through another vent hose which exits the
fuselage to run along the left landing gear leg to the wheel cover, where it is vented to the outside of
the aircraft.
To drain the tanks they all have a flush drain valve located at the lowest point that allows appropriate
drainage.
To avoid impurity there are filters installed at the pickup points of each tank and also there is a fuel
filter in between the fuel selector valve and the fuel pump.
For security reasons an electrically driven auxiliary fuel pump is installed in addition to the mechanical
driven fuel pump of the motor. The pump has a bypass and is able to supply the motor at takeoff
conditions. It also can be used as a boost pump. The switch is located on the righthand side electrical
panel of the cockpit.
To indicate the amount of fuel there are probes installed in each tank. The wing tank indicators use a
float device / potentiometer technology and the main tank has a capacitive operated indicator.
To verify the fuel indication in the tanks, the use of dipstick XA-2840-230 is highly recommended.