THRUSH AIRCRAFT, INC – MODEL S2R-R1340
AIRCRAFT MAINTENANCE MANUAL
8-2
Effective: 01/01/08
INSTRUMENTS
GENERAL DESCRIPTION
The standard instruments are located on
three panels in the cockpit. An upper
panel, a left lower panel, and a right
lower panel. The left lower panel
contains an oil temperature gauge, oil
pressure gauge, fuel pressure gauge,
hour meter, airframe related electrical
switches and the fuel quantity gauge. A
clock is optional. The right lower panel
contains the voltmeter, ammeter, and
circuit breakers. The upper instrument
panel contains the manifold pressure
gauge, tachometer, air speed indicator,
altimeter, “wet” compass, stall warning
light and turn coordinator. If the airplane
is certified for night flight, all instruments
are lighted with a post light or internally
lighted and controlled with rheostats
located on the left lower panel.
Optional instruments and gauges are
available upon request. A few of the
optional instruments are hopper
quantity, Micronair™ chemical flow
meter, Crophawk™ chemical flow
meter, encoding altimeter, artificial
horizon, electric turn and bank, vertical
speed, and directional gyro.
INSTRUMENT SYSTEM
MAINTENANCE
Unless otherwise specified, field
maintenance of instrument systems is
limited to removal and replacement of
defective instruments and transmitters;
authorized in-service adjustment of
transmitters and instruments; and repair
of instrument systems between the
instrument and signal source
(transducer). Reliability of the various
instruments and related systems can be
sustained by routine inspection of
electrical wiring for chafing and electrical
connections for security. All fluid
pressure, pitot pressure, and static line
connections must be tight at all times
and lines must be correctly routed and
secured. Electrical wiring must be free
from chafing, properly connected and
secured. Instrument ports and lines
disconnected during system
maintenance must be capped or
plugged immediately to prevent the
entrance of foreign material and
consequent instrument malfunction.
Maintenance procedures pertaining to a
specific instrument or system are
contained in subsequent sections. As a
general rule, it is recommended that the
instrument signal source and means of
transmission to the instrument be
inspected and functionally checked
before changing an instrument. If a new
instrument or a transducer is available, it
may be expedient to utilize them in the
system to determine if the malfunction is
in the instrument, signal source or
interconnecting line.
FLIGHT INSTRUMENTS
Ref. Figure 8-1, 8-2 & 8-3
Flight instruments consist of the
magnetic compass, airspeed indicator,
altimeter and turn coordinator. The
pitot-static system provides pitot
(dynamic) and static (atmospheric) air
pressure to the airspeed indicator and
static air pressure to the altimeter.
PITOT-STATIC SYSTEM
The pitot head is installed on the right
wing lower surface outboard of the tie-
down ring and provides pitot pressure.
A heated pitot head is available as an
option. The pitot pressure line is routed
to the forward side of the wing main
spar and then inboard through the root
rib. It is then routed up to the fuel vent
line, across to the left side of the
fuselage, and then aft to the cockpit.
The static pressure ports are located on
both sides of the aft fuselage and are
