TM 1-1510-225-10
3B-5
VOICE, located on the copilot’s sidewall circuit breaker
panel.
b. Controls, Indicators, and Functions. Refer
to Figure 3B-2.
(1) Go-No-Go Self-Test Meter. Provides
visual indication of Go-No-Go during preflight self-test.
(2) TEST Switch. Allows testing of recording
mode. Meter indicates self-test Go/No -Go indication
and an aural tone is produced through headset jack.
(3) ERASE Switch. Permits erasure of
recording at end of flight. To prevent accidental
erasure, the switch must be held for 2 seconds with
the landing gear extended and the weight of the
aircraft on the landing gear and the parking brake set.
(4) HEADSET Jack . Allows monitoring of
voice recordings, after a 2-second delay, and an aural
tone during self-test.
3B-12. FLIGHT DATA RECORDER OSA .
a. Description. The digital flight data recorder
system (referred to herein as a crash data recorder)
continuously records flight data inputs for the last
25 hours of flight. The flight data parameters recorded
are
heading,
altitude,
vertical
acceleration,
and
airspeed. The data is recorded on a continuous loop,
¼ inch, self -lubricating magnetic tape bundle. The
tape is drawn out of the hub and returned to the supply
reel at the outer periphery of the bundle after having
passed the write and read heads. The tape capsule is
protected by an inner aluminum casing, an isothermal
shield, an outer stainless steel casing, and an outside
steel dust cover. The construction of the cases
provide survivability assurance, while the isothermal
shield provides protection from temperatures. There
are no pilot accessible controls or switches associated
with the recorder. Its operation is completely
automatic. An impact switch, mounted in the aft
avionics compartment, controls power to the recorder.
If the impact switch is subjected to a 2.5 G shock, the
recorder is electrically disconnected to prevent further
recording and erasure. A red light located on the
impact switch case when illuminated indicates the
switch has been actuated. Pressing the reset button
located adjacent to the impact switch light causes the
light to extinguish and restores power to the recorder.
b. Power. The recorder system is powered
through a 1-ampere 115 Vac circuit breaker, placarded
RECORDER POWER / FLT located on the copilot’s
sidewall circuit breaker panel.
c. Underwater Locator. A battery powered,
acoustic underwater locator beacon assembly is
mounted on the front panel of the crash data recorder.
The unit consists of a self-contained battery, an
electronic module, and a transducer. The battery is
shock mounted and is separated from the electronic
module by a bulkhead in the case. The beacon
(pinger) radiates a pulsed acoustic signal into the
surrounding water upon activation of its water-
sensitive switch, and will activate automatically on
submersion in salt or fresh water with an operating life
expectancy of 30 days to a depth of 20,000 feet.
1. Meter
2. TEST Switch
3. ERASE Switch
4. HEADSET Jack
Figure 3B-2. Cockpit Voice Recorder
Control Unit OSA
Section III. NAVIGATION
3B-13. NAVIGATION EQUIPMENT GROUP.
The navigation equipment group provides the
pilot and copilot with instrumentation required to
establish and maintain an accurate flight course and
position, and to make an instrument approach under
Instrument Meteorological Conditions (IMC). The
navigation
configuration
includes
equipment
for
determining attitude, position, destination range; and
bearing, heading reference, and ground speed.
3B-14. FLIGHT DISPLAY SYSTEM (FDS -255).
a. System Overview. The Flight Display
System (FDS-255), is a replacement for existing
electromechanical Attitude Direction Indicator (ADI)
and
Horizontal
Situation
Indicator
(HSI)
flight
instruments.
The top and bottom displays are physically
identical. The top display is configured as an
