THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
1-6
Effective: 01/01/08
The electrically driven fuel boost pump
provides boosted fuel pressure to the
engine during starting. The electric driven
fuel boost pump discharge is then routed
through a 25-micron main fuel filter to the
carburetor. A separate electrically actuated
primer pump injects fuel directly into the air
intakes of the top five cylinders to facilitate
engine starting.
The fuel tank vent system is designed to
keep the fuel spillage to a minimum. The
fuel tanks are vented through tubing
connected at both the inboard and
outboard ends of the individual fuel tanks
to the centrally located vent system in the
fuselage. Ram air enters a vent scoop, on
the fuselage, under the left wing and
pressurizes the vent system to maintain
positive pressure on the fuel tanks. The
vent system is provided with two quick
drains, located on the fuselage under each
wing, to drain any fuel that might have
gotten into the tanks outboard vent lines.
The fuel quantity gauge is located on the
lower left instrument panel. The fuel
quantity indicating system consists of two
transmitters, one indicator gauge, and an
L/H or R/H tank fuel quantity selector
switch. A transmitter installed in each wing
tank transmits an electrical signal to the
single fuel quantity indicator. The
instrument reads the left or right fuel tank
singularly, as chosen by the fuel quantity
selector switch, adjacent to the fuel
quantity indicator gauge on the instrument
panel.
The two fuel tanks are serviced through
filler ports located on the top of each wing.
The filler ports incorporate security chains
to prevent the loss of the fuel caps.
Service the aircraft from refueling facilities
that utilize proper ground handling
equipment and filter systems to remove
impurities and water accumulation from the
bulk fuel. If filtering facilities are not
available, filter the fuel through a quality
high-grade chamois. Fuel tanks should be
serviced after the last flight of each day to
reduce condensation and allow any
entrapped water accumulations to settle to
the fuel system drains, to be removed,
prior to the next flight.
Prior to the first flight of the day the wing
tanks, header tank and fuel filter should be
drained to check for the presence of water
or sediment in the fuel system. If there is a
possibility, at any time, that any tank may
contain water, the header tank and fuel
filter should be drained as necessary to
ensure no water exists in the fuel system.
For fuel system servicing information, refer
to Section 2.
LANDING GEAR, WHEELS &
BRAKES
The main landing gear is a welded truss of
streamlined chrome-moly steel tube. The
left main gear and the right main gear are
symmetrical. The main tires are 29 x 11
on Cleveland 40-133 wheels with 30-98
dual caliper disc brakes. Inboard mounted
elastomeric shock struts absorb landing
and taxi stresses. The brake system has
individual toe brakes and individual park
brakes. The use of a special N-513
compound cup in each master cylinder
permits the use of MIL-H-5606, a heavy-
duty aviation hydraulic fluid. The tail gear
uses a 12.5 x 4.5 tire and tube mounted in
a symmetrical fork with a spring steel
shock absorber. The tailwheel is normally
locked but can be unlocked for full-
castering as the airplane is steered with
the brakes.
FLIGHT CONTROLS
The flight controls are of conventional
design employing extensive use of ball
bearings for low friction and smoothness of
operation. The aileron and elevator
controls are push rod systems and rudder
control is through tension cables. The
elevator trim control is actuated by a lever
that moves the tab to the desired position
through push rods. The wing flaps are
operated electrically and controlled by a
