Pipistrel Virus SW 121, Pilot Operating Handbook

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7-15
Virus SW 121
Pilot Operating Handbook
POH-121-00-40-001
PAGE REV. 0
PAGE
SECTION 7
AIRPLANE DESCRIPTION
APPROVED
toring functionality.
7.6.5 PROPELLER
The airplane is equipped with a constant-speed, two-blade composite
propeller (MT Propeller type MTV-33, diameter 1700 mm) and governor.
The propeller governor automatically adjusts propeller pitch to regulate pro-
peller and engine RPM. The propeller governor senses engine speed by
means of flyweights and the desired RPM setting through a cable connected
to the propeller control lever in the cockpit. The propeller governor boosts
oil pressure in order to regulate propeller pitch position. During stabilized
flight, the governor automatically adjusts propeller pitch in order to maintain
an RPM setting (propeller and throttle position). Any change in airspeed or
load on the propeller results in a change in propeller pitch.
7.7 FUEL SYSTEM
The airplane has two integral fuel tanks, one in each wing. The maximum
usable fuel quantity is 71.3 kg or 99 L (AVGAS or MOGAS, see chapter Lim-
itations for applicable fuel grades). Two (left and right) transparent vertical
tubes, which are visible from the pilot position and connected to the highest
and lowest points of each respective tank, serve as a visual indicator of the
fuel quantity available. Each tank has a strainer at the fuel outlet that pre-
vents any debris and/or foreign material from making its way towards the
engine. Venting of the fuel tanks is through the fuel caps.
There is a 1.5 L stainless steel collector tank (left and right) located just down-
stream from each fuel tank. It serves as a reserve fuel supply and prevents
engine starvation from occuring due to prolonged flight in side slip. After
leaving the collector tank the fuel goes through a drain valve (one per tank),
located on the bottom-side of the fuselage behind the baggage compart-
ment. Thereafter fuel enters the centrally-located fuel selector switch, which
has three different positions: LEFT, RIGHT, and OFF. When the LEFT position
is selected the engine is fed fuel from the left fuel tank and excess fuel is
returned to the LEFT collector tank. When the RIGHT fuel position is selected
the engine is fed fuel from the right tank and the excess fuel is returned to
the RIGHT collector tank. When the OFF position is selected the fuel selector
switch shuts off both the feed and return line. Once the fuel leaves the fuel
selector it is fed through a gascolator, which has a drain valve. The gascola-