SESKStuff Everyone Should Know
SESK: Stuff Everyone Should Know · sesk.info/pilot-vor-ident-maintenance

How can a pilot tell a VOR is out of service for maintenance?

Its Morse code identifier is removed and not transmitted.

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  1. Its Morse code identifier is removed ✔
  2. It broadcasts a siren tone
  3. It switches to a different frequency

Why: Always identify a VOR by its Morse code before using it. If the identifier is missing, the station may be under maintenance and should not be used for navigation.

Huh, didn't know that: The AIM says a station under maintenance may instead send a T-E-S-T code.

The dad joke
Why did the VOR stop sending Morse code? It had nothing more to dot or dash.
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References

Answer: Its Morse code identifier is removed. Always identify a VOR by its Morse code before using it. If the identifier is missing, the station may be under maintenance and should not be used for navigation.

  1. Pilot's Handbook of Aeronautical Knowledge FAA-H-8083-25C, Chapter 16 Navigation www.faa.gov/sites/faa.gov/files/18_phak_ch16.pdf
    If the VOR is out of service for maintenance, the coded identification is removed and not transmitted.
    Checked 2026-10-09.

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