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PilotSchool Knowledge Base

Understanding NDB and VOR Information

Introduction

This section focuses on understanding how to extract navigational aid information, specifically Non-Directional Beacons (NDB) and VHF Omnidirectional Range (VOR), from the En Route Supplement Australia (ERSA) and En Route Charts (ERC). Additionally, it covers the rated coverage of VOR systems up to 10,000 ft for the CASA PPL pilot license theory exam.

Non-Directional Beacon (NDB)

  • Symbology: NDBs are represented with specific symbols in aeronautical charts, which are part of the navigational aids (NAVAIDs) depicted.
  • Co-location: When co-located with a VOR/DME, the NDB symbol might not be shown to avoid clutter.
  • Serviceability: Pilots confirm serviceability through Morse code signals, indicated in the chart legends or marginalia.

Very High Frequency Omnidirectional Range (VOR)

  • Component: VOR is a crucial component of NAVAID symbology in charts.
  • Serviceability: Similarly to NDB, VOR serviceability is confirmed using Morse code. An asterisk (*) indicates any operational limitations, detailed in the ERSA FAC section.

Symbols and Annotations

  • Morse Code: Important for verifying the operational status of NAVAIDs like NDB and VOR.
  • Limitations Indicator: An asterisk signals any limitations or constraints.

Key Resources

  • Table of Symbols: Lists symbols for NDB, VOR, and other navigational aids.

Sources

Understanding ERC for NDB and VOR Details

Key Aspects of ERC

  • Purpose: ERCs depict major air traffic routes, controlled airspaces, and radio-navigation services including NDB and VOR stations.
  • Depictions: Include call signs, frequencies, and specific symbols for navigational aids.

Chart Symbology

  • Symbols: Clear indications with specific annotations for NDB and VOR.
  • Limitations: Noted using special symbols or annotations like an asterisk.
  • Bearings and Tracks: Distinct symbols for navigational purposes.
  • Special Notes: Include references to operating conditions and limitations.

Further Reading

VOR Rated Coverage up to 10,000 ft

Frequency and Channel Spacing

  • Frequency Band: Ranges from 108 to 117.975 MHz.
  • Channel Spacing: Primarily 100 kHz; however, 50 kHz channels are allowed under particular conditions.

Designated Operational Coverage (DOC)

  • Rated Coverage: Typically ranges from 25 NM to 200 NM, covering altitudes up to 60,000 ft.
  • Protection from Interference: DOC specifies coverage limits for ensuring flight safety.

Interference and Protection Protocols

  • Adjacent Channel Criteria: Requires a signal difference of 20dB to minimize interference.
  • Field Strength: Maintains a minimum field strength of 90 μV/m within DOC.

Additional Considerations

  • Potential FM Broadcasting Interference: Compatibility assessments are essential for overlapping frequencies with FM stations.

Sources

Conclusion

Understanding how to extract and interpret NDB and VOR information from ERSA and ERC is crucial for pilot navigation. Additionally, recognizing the rated coverage of VOR systems ensures safe flight operations up to 10,000 ft. These skills are vital for licensure and practical flight planning.