102: Avionics/Electrical Fundamentals
203 - AVIONICS/ELECTRICAL
Avionics / Electrical
203.1.1 state the purpose of the following communications
1.Intercommunications System (ICS)-AN/AIC-22, is
installed to provide intercommunication functions for crewmembers. A pilot,
co-pilot and TACCO operated public address (PA) system and radio- receiving
facilities are provided for each crew station. In addition, radio-transmitting
facilities are provided for the pilot, co-pilot, and TACCO, and NAV/COMM. Audio
monitor circuit is provided for special purpose equipment. Twelve (12) headsets
are provided: one for each crew station, the ordnance station, and the nose
2. Ultra High Frequency (UHF)-two identical
ARC-143UHF transceivers are installed in the P-3C aircraft. These radios are
functionally identical, however, they have different capabilities because of
aircraft wiring differences between the NAV/COMM stations and the flight
stations. The UHF-1 control box is mounted in the flight station. It can be
utilized for plain voice, cipher voice (VINSON) and UHF-2 control box is mounted
at the NAV/COMM station and is capable of plain voice, cipher voice, teletype,
data link, sonobuoy command and IACS.
3. Very High Frequency (VHF)- the ARC-182 VHF/UHF
radio system is installed in the aircraft incorporated AFC-485 to allow
communication with civilian and military agencies in the VHF-AM and UHF bands,
civilian maritime units in the high VHF-AM bands, and tactical military units in
the low VHF-FM bands. The control panel is located in the flight station on the
co-pilot side of the center control pedestal. The radio utilized for plain voice
4. High Frequency (HF)-two ARC-161 HF receiver /
Transmitters are installed in P-3C Aircraft. These identical radios are capable
of transmitting in the range of 2 to 29.9999 MHz. Both HF control boxes are
mounted at the NAV/COMM station. Operations of the two radio sets are
independent of each other. However an interlock automatically grounds the unused
radio when a mike is keyed on either HF. Both HF's are capable of plain voice,
cipher voice, Teletype and data link.
203.1.2 state the purpose of the
following navigation equipment
1. Inertial Navigation System (INS)-An automatic
aid to navigation that is independent of outside references. An INS is a portion
of the tactical system that provides accurate velocity, attitude, and heading
data processing system. This overall system permits accurate weapons delivery.
To function properly, the system must be aligned with reference to initial
conditions of altitude, latitude, and longitude. The aircraft gyros,
accelerometers, synchros, servos, and computers continually monitor aircraft
heading, attitude, and horizontal and vertical velocities. Any change in the
aircraft latitude, longitude, or altitude involves a change in its speed or
direction of motion. The inertia's extremely sensitive accelerometer resists
these changes. The computers continually recalculate the movement of the
aircraft based on the latest changes recorded by the accelerometers. The
computers use these calculations to provide a constantly updates readout of the
aircraft's geographical position.
2. Tactical Air Navigation (TACAN)-the navy uses
TACAN as the primary navigation aid for carrier based aircraft. TACAN has
integrated distance-measuring equipment (DME). The size of the system allows it
to be based aboard ship and gyro-stabilized for pitch, roll, and
3. Global Positioning System (GPS)- the
AN/ANR-151 (V) GPS is a world wide, all weather positioning system that provides
the NAV/COMM with a fixed position readout that is accurate to 5 to 8 meters
when operated with proper AS/AS crypto installed. In addition to position
information, the GPS provides a display of various navigational and tracking
4. Automatic Direction Finder (ADF)-frequencies
between 100 and 1750 KHz.
203.1.3 State the purpose of the
following tactical equipment
On-Top Position Indicator
(OTPI)- the OTPI receiver control panel, located on the center pedestal of
the flight station, enables the OTPI receiver to provide bearing to a selected
Tactical Computer- the
CP-2044/ASQ-212 digital data computer is a real-time multipurpose digital
computer. The central computer uses multiple processors and dual-bus
architecture to provide high processing performance, configuration options and
growth capabilities. It operates with peripheral devices (such as a magnetic
tape unit, printers, displays together with other input/output devices) in a
primarily digital data system.
Sensors- the ARR-72 sonobuoy receiver system consists of 31 fixed tuned
receivers that receive RF inputs form two blade antennas.
Radio Detection and
ranging (RADAR)- the APS -115 is a radio device used to detect objects at
distances much greater than visually possible. Detectable objects include
aircraft, ships, land areas, clouds, and storms. In addition to detecting these
objects, the radar shows their range and relative position.
Identification Friend or
Foe (IFF) -the APX-76 an electronic system that allows a friendly craft to
identify itself automatically before approaching near enough to threaten the
security of other naval units.
Magnetic Anomaly Detector
(MAD)- the ASQ-81 system is equipment that utilizes the principle that a
metallic submarine disturbs lines of force of the Earth.
Countermeasures (ESM)- the ALR-66 gathers intelligence from the enemy's
electronic devices and make them ineffective. Electronic countermeasures consist
of two general types of actions- passive and active. The ULQ-16 is a pulse
analyzation system used in conjunction with the host system for determining
Infrared Detection System
(IRDS)- the AAS-36 converts infrared radiation emanating form a heat source.
The IRDS display targets images in a television-type display on a CRT located at
the non-acoustic operator station. IRDS is a passive system, operating in the
8-14 micron range.
Inverse Synthetic Aperture
Radar (ISAR) - the APS-137 radar is a processing system that generates true,
recognizable, two-dimensional images of any selected ship target.
203.1.4 State the purpose of the
following special mission equipment
AVX Electro-Optical (EOA)-
an advanced Electro-optical (EO) imaging system that provides high
-resolution photography and video.
APG-66 RADAR- an
airborne, multimode, digital, pulse Doppler system designed to provide all
weather detection of airborne and surface targets in low and high
203.1.5 State the function of the
Battery-provides a reserve source of electrical power for select electrical
systems. During normal aircraft operations, the generator maintains the battery
in a charged state.
2.Main Alternating Current-the P-3
utilizes AC as the primary electrical powers source. The AC power requirements
are supplied by four interchangeable brush less generator that supplies 120
Volts; three phase power at 400 HZ.
the heart of the DC power system is the transformer rectifier unit.
Transformer-rectifiers 1&2 receive AC power directly from the main AC buses
A and B, respectively. They in turn rectify the AC input to a 28-volt DC output
fro use at the main DC bus. Transformer-rectifier 3 receives its power input
from the NEAC bus and routes its 28VDC output to the MEDC.
4.Spervisory Panel-each generator
has an associated supervisory panel located in the main electrical load center.
Each contains its respective GCR, ACR, and voltage regulators. The panel
provides over-voltage, under voltage, off-frequency and feeder fault protection
to their respective generators.
The left and right main AC buses provide power to
non-essential equipment through the aircraft. The monitor AC bus currently has
no load attached to it. When used, it provides power to non-essential equipment
only. With both generators operating, AC essential buses # 1 & #2 and the
115 Volts AC instrument bus power safety-of- flight equipment. The main
generators normally supply power to these two buses, but they also tie to the
emergency generators when it is in operation. A step down transformer supplies
26 VAC fro the instruments and navigation systems. The output of the transformer
also provides power to safety-of-flight
Strobe lights-two high
intensity strobe lights are installed along side the centerline on the aft
fuselage, top and bottom. They provide anti-collision warning to other
Wing tip Lights-wing
position lights are installed in the tips of each wing. The port wing tip light
is RED and the starboard wing tip light is GREEN. The different color wing tips
are used fro identifying the heading of approaching aircraft in flight.
Lights-installed at the trailing edge of the port and starboard wings,
between the inboard and outboard nacelles. These lights are used during take
off, approach, and landings.
Tail Lights-the tail
position lights are located on the bottom of the aft fuselage and the top
forward section of the MAD boom.
on the left and right sides of the nose gear struts. These lights are used
For comments contact:
AZC(AW/NAC) Kimberly King
AT1(AW) Toni Washington