AhaBulbStuff Everyone Should Know
AhaBulb: Stuff Everyone Should Know · ahabulb.com/pilot-east-is-least

Converting a true course to magnetic, what do you do with an easterly variation?

Subtract it. East is least, west is best.

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  1. Subtract it ✔
  2. Add it
  3. Ignore it below 10,000 feet

Why: The FAA handbook says to subtract east variation and add west variation. The memory aid is 'east is least, west is best.'

Huh, didn't know that: In the US, the compass needle points east of true north on the west coast and west of true north on the east coast.

The dad joke
Why did the compass go to therapy? It had issues with direction.
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References

Answer: Subtract it. The FAA handbook says to subtract east variation and add west variation. The memory aid is 'east is least, west is best.'

  1. Pilot's Handbook of Aeronautical Knowledge, Chapter 16 Navigation (FAA-H-8083-25C) www.faa.gov/sites/faa.gov/files/18_phak_ch16.pdf
    Remember, if variation is west, add; if east, subtract.
    Checked 2026-10-07.

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