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SESK: Stuff Everyone Should Know · sesk.info/ifr-vor-ground-4

At a VOR test signal or ground checkpoint, what is the maximum permitted bearing error?

Plus or minus 4 degrees.

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  1. Plus or minus 4 degrees ✔
  2. Plus or minus 2 degrees
  3. Plus or minus 6 degrees

Why: 91.171 allows a maximum error of plus or minus 4 degrees when checking against a VOR test signal or a designated ground checkpoint on the departure airport.

Huh, didn't know that: A test signal can also be radiated by a certificated repair station with the right ratings.

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References

Answer: Plus or minus 4 degrees. 91.171 allows a maximum error of plus or minus 4 degrees when checking against a VOR test signal or a designated ground checkpoint on the departure airport.

  1. 14 CFR 91.171 VOR equipment check for IFR operations www.law.cornell.edu/cfr/text/14/91.171
    the maximum permissible bearing error is plus or minus 4 degrees
    Checked 2026-10-10.

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