ATA 23 Communication

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ATA 23 Communication

• The communication system allows crew members to
  communicate with each other, from the cockpit and
  from the ground.
• They can also communicate with the passengers,
  other aircraft and the ground stations.
• Speech Communication Systems (23-10)
• The speech communications system controls the VHF
  and the HF radios. The Radio Control Panels (RCP)
  control and allow for selection of specified
  frequencies and the mode (AM, SSB) for the HF
  system.

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ATA 23 Communication

• High Frequency (HF) Communication System (23-11)

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ATA 23 Communication

• High Frequency (HF) Communication System (23-11)
• Each HF communication system provides amplitude
  modulated (AM) and single-side band (SSB) voice
  communications between the airplane and ground
  stations or other airplanes. Propagation
  characteristics of the HF system are suitable for
  long distance communications.
• Communications take place in the 2 to 30 MHz
  frequency range.
• Two independent HF communication systems provide
  long-range air-to-ground and air-to-air two-way
  voice communications.
• The left and right HF communication systems
  operate in the 2.000 to 29.999 MHz frequency
  range on 28,000 channels spaced at 1 KHz in the
  AM (Amplitude Modulated) or USB (Upper Sideband)
  mode, as selected.

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ATA 23 Communication

• Very High Frequency (VHF) Communication System
  (23-12)

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ATA 23 Communication

• Very High Frequency (VHF) Communication System
  (23-12)
• Three VHF communications systems are installed on
  the airplane. The systems provide short-range
  line-of-sight voice.
• Each VHF communications system provides
  amplitude-modulated (AM) voice communications
  with ground stations or other airplanes. The
  systems operate in the 118.00-MHz to 136.975-MHz
  frequency range in 25-kHz increments, or in the
  118.00-MHz to 136.990-MHz frequency range in
  8.33-kHz increments.

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ATA 23 Communication

• Airborne Cabin Telephone (23-19)
• The airborne cabin telephone system allows
  passengers and cabin crew to telephone anywhere
  in the world using international direct dialing
  (IDD).
• Emergency Locator Transmitter System (ELT)
  (23-24)
• The emergency locator transmitter (ELT) system
  provides an emergency locator signal to aid in
  search and rescue operations. The ELT transmits
  on international distress frequencies 121.5,
  243.0, and 406.025 MHz.

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ATA 23 Communication

• Satellite Communication System (23-25)

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ATA 23 Communication

• Satellite Communication System (23-25)
• The satellite communication (SATCOM) system
  provides voice and data communications capability
  for the flight crew and also provide a
  communication link for passenger voice and data
  communications. The SATCOM system supplies
  full-duplex telephone quality voice
  communications.
• The SATCOM system operates in the L-band
  frequency range. The uplink frequency
  (satellite-to-airplane) is 1530 to 1559 MHz. The
  downlink frequency (airplane-to-satellite) is
  1626.5 to 1660.5 MHz.
• The SATCOM system supplies voice/data signals
  over longer distances than the VHF communication
  system. The SATCOM system provides more reliable
  communications over oceanic regions than the HF
  communication system.

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ATA 23 Communication

• Satellite Communication System (23-25)

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ATA 23 Communication

• Aircraft Communications Addressing and Reporting
  System (23-27)
• The aircraft communications addressing and
  reporting system (ACARS) provides a ground to air
  and air to ground airborne communications data
  link. The system receives digital data and
  processes it for display to the flight crew and
  formats digital data of airplane parameters and
  operations for transmission to ground stations.
  Messages are coded to identify a specific
  airplane.

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ATA 23 Communication

• Aircraft Communications Addressing and Reporting
  System (23-27)
• The MU encodes the digital data for transmission
  as a series of 1200 Hz and 2400 Hz tones at 2400
  baud (future ACARS systems may operate with
  2400/4800 Hz at 4800 baud).
• A 1200 Hz tone indicates a bit change from the
  previous bit (0 to 1 or 1 to 0) while a 2400 Hz
  tone indicates no bit change (0 to 0 or 1 to 1).

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ATA 23 Communication

• Selective Calling (SELCAL) System (23-28)
• The SELCAL system allows a ground operator to
  alert a specific airplane. Coded tone signals are
  received with incoming HF or VHF transmissions
  and, when decoded by the designated airplane,
  signal the flight crew of an incoming call.
• The airplane has its unique four tone code
  resolved with a sixteen bit binary word. Four
  bits of the word determine each tone. Airplane
  wiring is installed to implement the unique 16
  bits for the airplane.

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ATA 23 Communication

• Passenger Address and Entertainment (23-30)
• The Advanced Cabin Entertainment/Service System
  or the Cabin Services System includes these
  systems
• Passenger Address System (23-31)
• Video Passenger Entertainment System (23-32)
• Passenger Service System (23-33)
• Audio Passenger Entertainment System (23-34)
• Passenger Flight Information Display System
  (23-38)

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ATA 23 Communication

• Service Interphone System (23-41)
• The service interphone system allows ground
  personnel to communicate with each other from
  various service stations around the airplane.
  They plug a boom/mic headset into jacks located
  at various points. Communication with the Flight
  Deck is possible by paralleling the service
  interphone system with the flight interphone
  system.

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ATA 23 Communication

• Cabin Interphone System (23-42)
• The cabin interphone system allows communication
  from the flight crew to the attendants and
  attendants to flight crew. Microphones/handsets
  in the passenger cabin are located in convenient
  locations for the flight attendants.
• Ground Crew Call system (23-43)
• The ground crew call system allows personnel in
  the flight compartment and servicing personnel on
  the ground outside the airplane to gain each
  others attention. They can then establish
  communications with the service interphone and
  the flight interphone systems.

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ATA 23 Communication

• Flight Interphone system (23-51)
• The flight interphone system interfaces with the
  communication radios and allows ground to
  airplane communication to occur. All push-to-talk
  (PTT) microphones, headsets and the oxygen mask
  microphones are part of the flight interphone
  system. This system also interfaces with most of
  the other chapter 23 cabin and crew communication
  systems.
• Various navigation systems interface with the
  flight interphone system. Included are the
  VOR/ILS, Marker Beacon, DME and ADF. These
  systems provide monitoring signals to the flight
  crew on the headsets or on the flight interphone
  speakers.

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ATA 23 Communication

• Static Dischargers (23-61)
• Static dischargers eliminate radio receiver
  interference which caused by a corona discharge
  emitted from the airplane surfaces as a result of
  precipitation static and engine charging by
  discharging static from the fuselage. This is
  done along the trailing edges of the wings, the
  horizontal stabilizer and the vertical
  stabilizer. This limits the interference that can
  be induced in the radio transceivers.

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ATA 23 Communication

• Static Dischargers (23-61)

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ATA 23 Communication

• Voice Recorder System CVR(23-71)
• The voice recorder records the flight crew
  communications and conversation for a maximum of
  30 minutes or 120 minutes. Inputs one through
  three are from the flight crew station
  microphones to the Audio Control Panels (23-51)
  and then to the Audio Management Unit.
• Input four is from the Remote Monitoring
  microphone in the flight deck overhead. This
  input sends all conversations in the flight
  compartment to the voice recorder. The voice
  recorder data may be erased when the airplane has
  landed and the parking brake is set.