TM 55-1510-219-10
the lights. To test the system, place the switch in the
momentary TEST position. The lights should illuminate.
Moving the switch to the OFF-RESET position will turn
the system off and reset it.
Section XI. FLIGHT INSTRUMENTS
2-77. TURN-AND-SLIP INDICATORS.
Turn-and-slip indicators are installed separately
on the pilot and copilot sides of the instrument panel
(fig. 2-28). The pilot's indicator provides yaw damping
information to the autopilot. These indicators are
gyroscopically operated. They use DC power and are
protected by 5-ampere circuit breakers placarded TURN
& SLIP PILOT or COPILOT on the overhead circuit
breaker panel (fig. 2-26).
2-78. AIRSPEED INDICATORS.
Airspeed indicators are installed separately on the
pilot and copilot sides of the instrument panel (fig. 2-
28). These indicators require no electrical power for
operation. The indicator dials are calibrated in knots
from 40 to 300. A striped pointer automatically displays
the maximum allowable airspeed (245 KIAS, 0.47 mach)
at the aircraft’s' present altitude.
2-79. PILOT'S ENCODING ALTIMETER.
The altimeter is located on the upper left side of
the instrument panel (fig. 2-28). The altimeter is a self-
contained unit which consists of a precision pressure
altimeter combined with an altitude encoder. The
display
indicates
and
the
encoder
transmits,
simultaneously, pressure altitude information to the
transponder. Altitude is displayed on the altimeter by a
10,000 foot counter, a 1000 foot counter, and a single
needle pointer which indicates hundreds of feet on a
circular scale in 50 foot increments. Below an altitude
of 10,000 feet, a diagonal warning symbol will appear on
the 10,000 foot counter. A barometric pressure setting
knob is provided to insert the desired altimeter setting in
inches Hg or millibars. A DC powered vibrator operates
inside the altimeter whenever aircraft power is on. If DC
power to the altitude encoder is lost, a warning flag
placarded CODE OFF will appear in the upper center
portion of the instrument face, indicating that the altitude
encoder is inoperative and that the system is not
reporting altitude to ground stations. Operating
instructions
are
contained
in
Chapter
3.
2-80. COPILOT'S ALTIMETER.
The copilot's altimeter is located on the upper
right side of the instrument panel (fig. 2-28). It displays
altitude by means of a 10,000 foot counter, a 1000 foot
counter, a 100 foot counter, and a single needle pointer
that indicates on a circular scale marked in 50 foot
intervals. Below an altitude of 10, 000 feet, a diagonally
striped symbol covers the 10, 000 foot indicator. A knob
is provided at the bottom right corner of the altimeter for
setting readings in the pressure windows.
2-81. VERTICAL VELOCITY INDICATORS.
Vertical velocity indicators are installed separately
on the pilot and copilot sides of the instrument panel
(fig. 2-28). They indicate the speed at which the aircraft
ascends or descends based on changes in atmospheric
pressure. The indicator is a direct reading pressure
instrument requiring no electrical power for operation.
2-82. ACCELEROMETER.
The accelerometer, located on the instrument
panel registers and records positive and negative G
loads imposed on the aircraft. One hand moves in the
direction of the G load being applied while the other two,
one for positive G loads and one for negative G loads,
follow the indicating pointer to its maximum travel. The
recording pointers remain at the respective maximum
travel positions of the G's being applied, providing a
record of maximum G loads encountered. Depressing
the push-to-reset knob at the lower left corner of the
instrument allows the recording pointers to return to the
normal position.
2-83. FREE AIR TEMPERATURE (FAT) GAGE.
The free air temperature gage, mounted outboard
of the pilot's seat indicates the free air temperature in
degrees Celsius.
2-70
