1.0 INTRODUCTION
    1.1 Purpose of this Document
    1.2 Related Documents
    1.3 System Functions
    1.4 System Description
    1.5 Unit Descriptions
    1.6 Interchangeability
    1.7 Regulatory Approval
2.0 INTERCHANGEABILITY STANDARDS
    2.1 Introduction
    2.2 Form Factors, Connectors and Index Pin
        Coding
    2.3 Interwiring
    2.4 Power Circuitry
    2.5 Environmental Conditions
    2.6 Cooling
    2.7 Grounding and Bonding
3.0 CCS SYSTEM DESIGN
    3.1 User Services
    3.2 Voice Services
    3.3 Facsimile Services (Not Applicable)
    3.4 Data Services (Not Applicable)
    3.5 Bearer Systems
    3.6 Configuration Updates
4.0 CTU DESIGN
    4.1 Introduction
    4.2 Reference Oscillator
    4.3 CTU to CDS Interfaces
    4.4 CTU to Bearer Systems
    4.5 CTU to Aircraft Interfaces
5.0 STIU DESIGN
6.0 PROVISIONS FOR TEST
    6.1 Introduction
    6.2 BITE Considerations
    6.3 Fault Display
    6.4 Self-Test Initiations
    6.5 Fault Monitor
    6.6 Monitor Memory Output
    6.7 Automatic Test Equipment
ATTACHMENTS
 1 Aeronautical Telecommunication System Architecture
 2 CTU Connector
 3 SITU Rear Connector
 4 CTU Interwiring Diagram
 5 SITU Interwiring Diagram
 6 CTU Environmental Categories
 7 CTU Interfaces
 8 SITU Interfaces
 9 CEPT E1 Interface Definition
 10 Gatelink Interface Definition
 11 CTU-SATCOM, NATS and TFTS CEPT E1 Layer 3
    Provisions
 12 SITU-SATCOM E1 Layer 3 Provisions
 13 CTU-NATS E1 Layer 3 Provisions
 14 CTU-TFTS E1 Layer 3 Provisions
 15 BITE Codes
 16 Location of CCS User Service Functions
 17 CTU to CDS CEPT-E1 Layer 3 Interface Provisions
 18 Packet Data Communications CEPT E1 Provisions
APPENDIXES
 A SDL Charts
 B Glossary of Abbreviations and Acronyms
ARINC Errata Report
ARINC IA Project Initiation/Modification (APIM)
 Guidelines for Submittal and ARINC