W DOC AIRBUS | AMM A320F

COMBINED VOICE AND DATA RECORDING / RECORDING AND AIRCRAFT LOCATING SYSTEM

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1. General

For the main function of the DFDRS refer to (Ref. AMM D/O 31-33-00-00)
The Cockpit Voice Data Recorder (CVDR) is a crush-survivable recorder which includes the functions of the Cockpit Voice Recorder (CVR) and the Flight Data Recorder (FDR).

CVDR system records:
  • The voice communication transmitted from, or received on, the flight deck by radio
  • The sound environment of the flight deck with the audio signals received from each boomset and mask microphones in use
  • The voice communication of flight crew members on the flight deck, who use the aircraft interphone system
  • The voice or audio signals identify navigation or approach Aircraft Integrated Data System (AIDS), heard into a headset or loudspeaker
  • The voice communication of flight crew members on the flight deck, who use the public address system.

The CVDR includes:
  • CVR
  • FDR
  • Data Link Recorder (DLR) function
  • Underwater Locator Beacon (ULB).

The CVR records the voice communication of the crew members.
The FDR records flight parameters sent by the Flight Data Interface and Management Unit (FDIMU).
The ULB is self-powered equipment attached to the CVDR. The ULB sends the ultrasonic signal of 37,5 KHz when the ULB water immersion-sensor detects water.

The primary function of the CVDR is to record cockpit voice, aircraft flight data, and aircraft traffic control for investigators in case of an aircraft incident/accident.

The CVDR has interfaces with:
F Schematic Block Diagram ** ON A/C NOT FOR ALL
  • Analog audio from the Audio Management Unit (AMU) and Cockpit Area Microphone (CAM)
  • CVR control panel
  • Air traffic control data from Air Traffic Control (ATC)
  • Digital flight data from the FDIMU
  • Flight warning data to Flight Warning Computer (FWC)
  • It also has a BITE interface with the Centralized Fault Display Interface Unit (CFDIU).
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2. Component Location

For Installation Zones and Location Numbers refer to (Ref. AMM D/O 31-33-00-00)
F CVDR - Component Location ** ON A/C NOT FOR ALL
FIN FUNCTIONAL
DESIGNATION		 PANEL ZONE ACCESS
DOOR		 ATA REF
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4TU CVDR1 312 31-33-00
5TU CVDR2 90VU 122 31-33-00
21TU COCKPIT AREA MICROPHONE 20VU 210 31-39-13
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10TV DMU/FDIU (FDIMU) 87VU 120 31-36-34
1WW1 FWC-1 85VU 127 31-53-34
1WW2 FWC-2 86VU 128 31-53-34
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3. System Description

For description of FDIMU refer to (Ref. AMM D/O 31-33-00-00)
The CVR function changes cockpit analog audio-signals to digital format and gives large-capacity digital-memory storage for digital data recording and datalink.

The FDR function gets and records samples of ARINC 717 aircraft data. The crash-survivable housing protects the recorded medium.
NOTE: The crash-survivable housing obeys the ED-112A environmental requirements.

The CVDR has recording-time capacity minimum of 25 hours for audio and datalink, and minimum of 25 hours for flight data. To gets the recording minimums, CVDR uses audio compression.

The ULB helps to find aircraft if there was an overwater accident. It is activated when the recorder is put fully into water. A lithium-free (alkaline) non-rechargeable battery lets the signal to be transmitted for 90 day.
A. CVDR Function
F CVDR Functional Diagram ** ON A/C NOT FOR ALL

The CVDR has following functions:
  • Audio Function: four analog audio channels are digitalized, compressed in software (S/W), and transmitted to the Crash Survivable Memory Unit (CSMU). Audio monitoring takes the post recorded audio-signals, decompresses them in S/W, mixes them and sends the result to the audio output on the aircraft interface board.
  • ARINC 717 function: CVDR S/W collects and transmits data to the CSMU.
  • Datalink function: collects data from ARINC 429 and transmits to the CSMU.
  • On-Board Maintenance System (OMS) function: ARINC 429 OMS function. S/W processes data and if necessary, specific information is sent to the CSMU for storage.
  • CSMU function: The CSMU is a unit in the CVDR where data is stored to protect it from fire or crash.
  • BITE function: Normal mode only.
B. DFDRS Function

For description of FDIU-part refer to (Ref. AMM D/O 31-33-00-00)
C. AIDS Function

For description of AIDS Function refer to (Ref. AMM D/O 31-36-00-00)
D. System Architecture

For description of DFDRS refer to (Ref. AMM D/O 31-33-00-00)
F CVDR Functional Diagram ** ON A/C NOT FOR ALL

The CVDR has the following internal components:
  • CPU board
  • Aircraft Interface (AI) board
  • CSMU

The CPU board filters, digitizes and encodes the audio input channels, receives the Greenwich Mean Time (GMT) time input, receives the datalink input, flight data, discrete input and output, and processes OMS I/O. It also gives the power supplies, microprocessor, interface to the CSMU and interface to the Ground Support Equipment (GSE).

The AI board gives the connector signal conditioning, input protection and main power supply filters.

The CSMU contains data on FLASH memory. It contains management functions including bad block management.
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4. System Power Supply

F POWER SUPPLY ** ON A/C NOT FOR ALL
  • The FDIMU is supplied from the AC-NORM busbar through the circuit breaker 5TV.
  • The QAR is supplied from the AC-NORM busbar through the circuit breaker 14TU, and from the DC-NORM busbar through the circuit breaker 9TU. The operation of the of the QAR is controlled by the power-interlock.
  • The SSFDR is supplied from the AC-NORM busbar through the circuit breaker 7TU. The operation of the SSFDR is controlled by the power-interlock.
  • The CVR is supplied from the DC-ESS busbar through the circuit breaker 23RK.
  • The LA is supplied from the DC-NORM busbar through the circuit breaker 9TU.
  • The power-interlock relays are supplied from the DC-ESS busbar through the circuit breaker 26RK.

    The busbar connection is as shown below:
    ---------------------------------------------------------
    COMPONENT VOLTAGE BUSBAR C/B
    ---------------------------------------------------------
    SSFDR 115 V AC 202XP NORM 7TU
    CVR 28 V DC 201PP NORM 23RK
    QAR 115 V AC 202XP NORM 14TU
    QAR 28 V DC 204PP NORM 9TU
    FDIMU 115 V AC 202XP NORM 5TV
    LA 28 V DC 204PP NORM 9TU
    ---------------------------------------------------------



F Power Supply ** ON A/C NOT FOR ALL

CVDR1 is supplied with 28 VDC by ESS BUS1 through circuit breaker 40TU.
CVDR2 is supplied with 28 VDC by NORM BUS2 through circuit breaker 42TU.
CVR control panel, parking brake logic and power interlock are supplied with 28 VDC ESS BUS1 through circuit breaker 41TU.
---------------------------------------------------------
COMPONENT VOLTAGE BUSBAR C/B
---------------------------------------------------------
CVDR1 28 V AC 401PP NORM 40TU
CVDR2 28 V DC 204PP NORM 42TU
QAR 115 V AC 202XP NORM 14TU
QAR 28 V DC 204PP NORM 9TU
FDIMU 115 V AC 202XP NORM 5TV
LA 28 V DC 204PP NORM 9TU
---------------------------------------------------------


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5. Interface
A. FDIU Input Sources

(Ref. AMM D/O 31-33-00-00)
B. FDIMU (FDIU-Part) Input Sources

(Ref. AMM D/O 31-33-00-00)
C. Parameters

The information about the parameters are in the Flight-Data Recording Parameter-Library (FDRPL).
D. FDIU Input/Output Pin Assignment

(Ref. AMM D/O 31-33-00-00)
E. FDIMU (FDIU-Part) Input/Output Pin Assignment

(Ref. AMM D/O 31-33-00-00)
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6. Component Description

(Ref. AMM D/O 31-33-00-00)
CVDR recording system has:
  • CVDR1
  • CVDR2
  • Cockpit area microphone.
A. Flight Data Interface Unit (FDIU)


(Ref. AMM D/O 31-33-00-00)
B. Flight Data Interface and Management Unit (FDIMU)

(Ref. AMM D/O 31-33-00-00)
C. Input/Output Characteristics

(Ref. AMM D/O 31-33-00-00)
CVDR1 and CVDR2 have:

Inputs:
  • FDR ARINC 717 input port
  • CFDIU ARINC 429 input port
  • ATC ARINC 429 input port.

Output:
  • ARINC 429 Data Link OMS/FWS output port.
D. Cockpit Voice and Data Recorder (CVDR)
F CVDR - Component Description ** ON A/C NOT FOR ALL

The investigators use CVDR to find the causes of an accident or incident. The recording speed is 1024 words/sec and has an option of 2048 words/sec.
The CVDR has four different connectors in the front side and one connector in the back side together with the ULB.

CONNECTOR NAME
FUNCTION
A
AMU analog channels and analog-digital ground
B
CVR analog inputs, voice erase, test, monitor, CTL Unit power, ATC messages and analog-digital ground
C
CAM digital audio and control, CRDC ARINC 429, CDAU ARINC 717, Power input, BITE function and analog-digital ground
D
Ethernet provision, camera image
GSE
Ground support equipment communication
E. Cockpit Area Microphone
F Cockpit Area Microphone ** ON A/C NOT FOR ALL
The CVR microphone is a remote area microphone collecting all cockpit sounds such as voice communications, aural alerts and all other ambient noises from cockpit as required by the applicable regulation.
One cockpit area microphone is installed in the aircraft and powered by CVDR1 (preamplifier is integrated in the microphone).
F. Digital Flight Data Recorder (DFDR)

(Ref. AMM D/O 31-33-00-00)
G. Linear Accelerometer (LA)

(Ref. AMM D/O 31-33-00-00)
H. Quick Access Recorder (QAR)

(Ref. AMM D/O 31-33-00-00)
I. PC-Card Quick-Access Recorder (PQAR)

(Ref. AMM D/O 31-33-00-00)
J. Optical Quick Access Recorder (OQAR)

(Ref. AMM D/O 31-33-00-00)
K. Wireless Ground Link - Quick Access Recorder (WGL-QAR)

(Ref. AMM D/O 31-33-00-00)
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7. Operation, Control and Indicating
F POWER INTERLOCK ** ON A/C NOT FOR ALL
F Power Interlock ** ON A/C NOT FOR ALL
A. Energization

(Ref. AMM D/O 31-33-00-00)
The power interlock is released for supply of the both CVDR with 28VDC, with the oil pressurization of one or both engines. The FDIMU is supplied directly from the busbar. A dimmable power bus supplies the control panel indicators. To do maintenance task or test on the ground and for preflight checks there is an override function to supply two CVDRs. When the RCDR/GND CTL pushbutton on the control panel is pushed, an electric latch holds the override function. The blue 'ON' pushbutton light comes on. The override function supplies the equipment until the RCDR/GND CTL pushbutton is pushed again or the automatic power interlock becomes active.
B. Control

(Ref. AMM D/O 31-33-00-00)
The CVDR1 and CVDR2 to provide audio feedback are interfaced with
  • 21VU control panel
  • 50VU audio plug panel.
The CVDR1 and CVDR2 to set a mark on the recording are interfaced with:
  • Event marker button on 112VU.
(1) Control Panel
F CTL PNL ** ON A/C NOT FOR ALL
Control panel 21VU has:
  • RCDR/GND CTL - The ground control pushbutton lets the crew manually start the recording of two CVDRs at any time while the aircraft is on the ground and all engines stopped (A/C is powered by the APU or external power).
  • RCDR/CVR TEST - This pushbutton is used to do a test of the recorder.
  • RCDR/CVR ERASE pushbutton - This pushbutton allows erase all the recorded data from the memory block unit.
(2) Audio Plug Panel
F Audio Plug Panel ** ON A/C NOT FOR ALL
The audio plug panel has:
CVR/HEAD SET jack and CVR boomset are connected in parallel with the socket on the CVDR to make maintenance easier.
(3) Event Marker
F Event Marker Button ** ON A/C NOT FOR ALL
The DFDR/EVENT button is located in the cockpit and lets the flight crew to set a mark in the CVDR1 and CVDR2 recording to identify a dedicated event, when the button is pressed. The status of the DFDR/EVENT is continuously monitored by the FDIMU for further recording.
C. Indication

(Ref. AMM D/O 31-33-00-00)
When you push the RCDR/GND CTL pushbutton on the control panel, an electric latch holds the override function. The blue RCDR/ GND CTL pushbutton light comes on.
The CVDR failure messages are started by the CVDR BITE system. The CVDR BITE system has a direct interface with the Centralized Maintenance System (CMS)/Centralized Fault Display Interface Unit (CFDIU).
The CMS/CFDIU uses ARINC 429 words and transmits continuously the following data:
  • General parameters, to help the systems to class the maintenance messages
  • Flight phase parameters, to make easier memorization of failure data.
The FWC monitors the CVDR buses. If the signal is missing, the FWC will transmit the BITE messages to the CFDIU for a post-flight report printing.
D. Lighting

(Ref. AMM D/O 31-33-00-00)
The RCDR control-panel has an integral light. The remote OVERHEAD PANEL LIGHT knob can be turned to decrease the illumination.
E. Monitoring
For Monitoring refer to (Ref. AMM D/O 31-33-00-00)
The CVDRs monitor internal functioning and based on this monitoring they give the maintenance messages that follow for service on ground.
For Test refer to (Ref. AMM D/O 31-33-00-00)
The CVR test function

The CVR test function can be activated through the RCDR/CVR TEST pushbutton switch on the CVR control panel. In order to have a RCDR/CVR TEST function performed, RCDR/GND CTL pushbutton switch needs to be pressed and the CVDRs need to be in recording mode. Each CVDR will do the CVR test and report any failures to FWS through the related bit. If CVDR1 and CVDR2 tests fail, a CVR FAULT message shows on the ECAM. The minimum push-to-test action duration must be of 0.1 seconds. During the test, CVR function will continues recording on each CVDR. If no CVDR1 failure is detected, a 600 Hz tone is heard on the CVDR1 monitor output only. If there is a CVDR1 failure the output stays muted (no tone).
NOTE: The CVDR2 failure has no effect on a 600Hz tone. Only the CVDR1 monitor output is connected to the CVR control panel.
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8. Test Bite
A. Conditions of Power-Up Test Initialization

(Ref. AMM D/O 31-33-00-00)
The computer must be de-energized for 1 second.
A/C configuration:
  • A/C on ground and engines stopped.
B. Progress of Power-up Test

(Ref. AMM D/O 31-33-00-00)
A power up self-test runs at every power on and a CVR test is required by FCOM during each cockpit preparation. The recorded data are downloadable on the A/C through Ethernet through the GSE connectors. The monitoring of the audio channels and device functions can be controlled by the push-buttons in the cockpit.
The system is designed to monitor audio condition as well as equipment failure status during operation, with a period less than 5 seconds.
C. Results of Power-up Test

(Ref. AMM D/O 31-33-00-00)
Test passed:
  • None.

Test failed:
  • ECAM warning: "RECORDER CVR FAULT" and/or "RECORDER DFDR FAULT".
D. CVDR Failure Messages

-----------------------------------------------------------------------------
! ATA - NO ! Name of Failure ! EXT/INT ! Class !
!------------!-------------------------------------------!-----------!--------!
! 31-39-33 ! CVR1 Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! CVR2 Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! FDR1 Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! FDR2 Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! CONTROL UNIT PRE-AMPLIFIER Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! CVDR RECORD ENABLE Failure ! INT ! I !
! ! ! ! !
! 31-39-33 ! ATC DATALINK Failure CPIOM/CVDR ! INT ! II !
! ! ! ! !
! 31-39-33 ! CMS COM Failure CVDR/SCI ! INT ! III !
! ! ! ! !
! 31-39-33 ! FLIGHT DATA INPUT BUS ! INT ! II !
! ! ! ! !
! 31-39-33 ! POWER SUPPLY INTERRUPT ! INT ! I !
! ! ! ! !
! 31-39-33 ! AUTO RESET ! INT ! I !
! ! ! ! !
! 31-39-33 ! INVALID HPP RECORDING SYSTEM CONFIGURATION! INT ! III !
! ! ! ! !
! 31-39-33 ! INVALID HPP VOICE MODE CONFIGURATION ! INT ! I !
! ! ! ! !
! 31-39-33 ! INVALID HPP ARINC 717 RECORDING SPEED ! INT ! I !
! ! CONFIGURATION ! ! !
! ! ! ! !
! 31-39-33 ! INVALID HPP DATALINK MODE CONFIGURATION ! INT ! I !
! ! ! ! !
-----------------------------------------------------------------------------

E. DFDRS Failure Messages

(Ref. AMM D/O 31-33-00-00)
[Rev.10 from 2021] 2026.04.01 08:29:46 UTC
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