title: DO-242A
text: # DO-242A
  
  DO-242A is an aviation system standard published by RTCA, Incorporated. It contains minimum aviation system performance standards (MASPS) for Automatic Dependent Surveillance-Broadcast (ADS-B). These standards specify operational characteristics that should be useful to designers, manufacturers, installers, service providers and users of an ADS-B system intended for operational use on an international basis. DO-242A provides a view of the system-wide operational use of ADS-B, but does not describe a specific technical implementation or design architecture meeting these operational and technical characteristics.
  
  ## Outline of contents
  
  * Purpose and Scope
     * Introduction
     * System Overview
     * Operational Applications
     * Verification Procedures
  * Operational Requirements
     * General Requirements
     * System Performance - Standard Operational Conditions
  * ADS-B System Definition and Functional Requirements
     * System Scope and Definition of Terms
     * ADS-B System Description
     * System Requirements
     * ADS-B Messages and Reports
     * ADS-B Subsystem Requirements
     * ADS-B Functional Level Requirements
  * Procedures for Requirement Verification
  * Appendix A: Acronyms
  * Appendix B: Definition of Terms
  * Appendix C: Bibliography and References
  * Appendix D: Near-Term ADS-B Applications
  * Appendix E: Other Applications
  * Appendix F: Efficient Spectrum Utilization
  * Appendix G: Design Tradeoff Considerations
  * Appendix H: Receive Antenna Coverage Constraints
  * Appendix I: Integrity Considerations for ADS-B Applications
  * Appendix J: Accuracy and Update Period Analysis
  * Appendix K: Latency and Report Time Error Data
  * Appendix L: Track Acquisition and Maintenance Requirements
  * Appendix M: Examples of On-Condition Report Formats
  * Appendix N: Intent Guidance Material for Future ADS-B Intent Broadcast
  * Appendix O: Determination of Intent Information Exchange Requirements for Air-Air Encounter Alerting and De-Confliction
  * Appendix Q: Future Air-Referenced Velocity (ARV) Broadcast Conditions
  * Appendix R: Determining the Navigation Accuracy Category for Velocity ($\mathrm {NAC} _{v}$)
  