b. Microphone Jacks. The pilot and copilot
are each provided a microphone jack, placarded MIC,
located on the extreme left and right sides of the
instrument panel, Figure 2-17, for use with the hand
held microphone or headset microphone. There is a
microphone jack for the oxygen mask microphone,
located next to the oxygen outlets.
(1) MIC HEADSET Jack . This jack provides
a means of connecting microphone headset assembly
to audio system.
(2) MIC Jack . This jack provides a means of
connecting handheld microphone with pushtotalk
capability to the audio system.
c. Microphone Jack Selector Switches. The
pilot and copilot are each provided with a switch,
placarded MIC HEADSET / OXYGEN MASK, located
on the extreme left and right sides of the instrument
Switch. Selects which microphone will be connected
to audio system.
(2) MIC HEADSET. Utilizes either hand-held
microphone or headsetmicrophone assembly with
(3) OXYGEN MASK. Utilizes microphone in
oxygen mask assembly with audio system.
d. External Headset-Microphone Jack. A
jack on the nose gear strut, placarded MIC JACK, is
available for use by ground personnel. The jack
connects headphones and microphone to the aircraft's
e. Cockpit Floor Foot Microphone Switch. A
floormounted foot microphone switch is installed on
the floor on the copilot's side. The switch allows the
copilot to key the system selected by the transmitter
selector switch on the audio control panel while
performing other operations.
Section III. NAVIGATION
3-6. NAVIGATION DESCRIPTION.
The overall navigation equipment group provides
the pilot and copilot with the instrumentation required
to establish and maintain an accurate flight course and
position and to make an approach on instruments
under Instrument Meteorological Conditions (IMC).
The navigation configuration includes equipment for
determining attitude, position, destination range and
bearing, heading reference and groundspeed. The
common avionics in the navigation equipment group
consists of the gyromagnetic compass systems.
3-7. GLOBAL POSITIONING SYSTEM (KLN 90B).
System (GPS) is a satellite-based radio navigation
system that utilizes precise range measurements from
GPS satellites to determine precise position anywhere
in the world. The KLN 90B provides en route
navigation information and non-precision (except
(1) KLN 90B Panel. Located above the
weather radar on the instrument panel are the GPS
sensor, the navigational computer, a CRT display, and
all controls required to operate the unit, Figure 3-1. It
also houses the database cartridge that plugs directly
into the back of the unit. Refer to Figure 31.
(2) External Annunciators/Switches. A panel
located just to the right of the fire handles D2 T or
above the KLN 90B control panel C D1 on the
instrument panel contains switches to select OBS or
LEG during en route navigation and a switch to arm
the unit during approach. It also has annunciators to
indicate when a message is active, when waypoint
sequencing is about to occur, and when altitude
alerting is occurring. The annunciator panel also
contains a jack to load the database from a laptop
computer. Refer to Figure 3-2.
(3) Antenna. A GPS antenna is located on
the top of the fuselage at approximately STA 220.
c. Power. Vdc to the KLN 90B is provided
through a dc circuit breaker panel through a 5-ampere
circuit breaker labeled KLN 90B C D or FMS #2 T1 .