ARINC 557 : 1964

1.0 INTRODUCTION
  1.1 Background of this Project
  1.2 Relationship Between this Characteristic and the
               FAA Developmental Specification
  1.3 Relationship Between this Characteristic and
               the FAA Technical Standard Order
  1.4 Purpose of the FAA "Installation Requirement"
               Material
  1.5 Regulatory Approval
  1.6 Function of this Equipment
  1.7 Equipment Configuration
  1.8 Reference Publications, Specification & Reports
  1.9 Possible Procurement of this Equipment for Use
               in Military Aircraft
  1.10 Purpose of this Equipment Characteristic---The
               Requirement for Interchangeability
  1.11 Dependence in this Equipment Characteristic upon
               Performance Requirements in the FAA TSO
2.0 INTERCHANGEABILITY
  2.1 Interchangeability Definitions
  2.2 Interchangeability Requirements for the Airborne
               Voice Recorder
  2.3 Recorder Unit Form Factor and Connector
  2.4 Control Unit Form Factor and Connector
  2.5 Cockpit Microphone Physical Characteristics
  2.6 Standard Interwiring
  2.7 Electric Power Requirements
  2.8 Connection of Recorder to Audio Distribution
               System
  2.9 Cockpit Microphone Location and Mounting
  2.10 Monitor System Wiring Provisions
  2.11 Optional Timer Connection to Flight Data Recorder
  2.12 Microphone Filter Selection Circuitry
  2.13 Microphone Gain Selection Circuitry
  2.14 Bulk Erase Circuitry
  2.15 Control Unit Lighting
  2.16 Location of Recorder Unit in Aircraft
3.0 SYSTEM DESIGN AND PERFORMANCE REQUIREMENTS
  3.1 Recording Channels
  3.2 Recording Time
  3.3 Tape Speed
  3.4 Tape Magazine
  3.5 Recording Level and Channel Input Characteristics
  3.6 Frequency Response Characteristics
  3.7 Distortion at Normal Recording Level
  3.8 Dynamic Range
  3.9 Flutter and Wow
  3.10 Cross-Talk
  3.11 Monitor System Design
  3.12 Monitor Audio Output
  3.13 Erase System Design
  3.14 Recording Head Alignment
  3.15 Environmental and Special Requirements for the
               Voice Recorder System
  3.16 Optional Shop Testing Provisions
  3.17 Interference Pickup by System
4.0 DESIGN REQUIREMENTS RELATED SPECIFICALLY TO THE
               CONTROL UNIT
  4.1 Pre-Amp Input and Output Levels and Impedances
  4.2 Automatic Gain Control
  4.3 Attenuation Adjustment
  4.4 Frequency Response-Microphone Pre-Amplifier
  4.5 Filter Characteristics
  4.6 Power Supply for Pre-Amplifier
5.0 MICROPHONE CHARACTERISTICS
  5.1 Microphone Impedance and Sensitivity Standards
  5.2 Microphone Magnetic Field
  5.3 Microphone Distortion Limits
ATTACHMENTS
  1 Notes Applicable to Attachments
  2 Standard Interwiring
  3 Connector Pin Assignments
  4 Connector Pin Assignment Control Unit
  5 Control Unit Wiring
  6 Power Circuit Alternatives
  7 Erase Circuit Details
  8 Vibration Environment - Recorder Unit
  9 Doghouse Size Limits
  10 Tables A and B (Recorder Unit without Pre-Amp and
               Recorder Unit with Mike and Pre-Amp)
  11 Microphone Output
APPENDICES
  1 List of Reference Documents
  2 FAA Requirements for the Installation of Airborne
               Voice Recorders in Airline Aircraft
  3 FAA "Minimum Performance Standards for Aircraft
               Flight Crew Communications Recording Equipment"
  4 Alternative design which is Required to be
               provided for, with respect to Automatic Gain
               Control Operation versus Tape Saturation Limiting
  5 Chronology, Participation and Bibliography of
               this project

Provides basic requirements for an airborne voice recorder system intended for crash investigation, having the capability of recording a total of four channels of information. It is designed to record continuously with erasure immediately before recording and with the last 30 minutes of recording always remaining in the unit.