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SESK: Stuff Everyone Should Know · sesk.info/pilot-compass-deviation

What causes deviation error in an airplane's magnetic compass?

Metals and electrical systems inside the aircraft.

  1. A northerly turning error
  2. Metals and electrical systems in the aircraft ✔
  3. The gap between true and magnetic north

Why: Deviation comes from magnetic influences inside the airplane, like radios, lights, the engine, and metal parts. The gap between true and magnetic north is variation, a different error.

Huh, didn't know that: Each airplane has its own compass deviation card, made by a procedure called swinging the compass.

The dad joke
I'm reading a book about magnetism. I find it very attractive.
Like this card?
Play the game

Sources

  1. Pilot's Handbook of Aeronautical Knowledge, Chapter 16 Navigation (FAA-H-8083-25C) https://www.faa.gov/sites/faa.gov/files/18_phak_ch16.pdf
  2. FAA Private Pilot Airplane sample questions https://www.faa.gov/sites/faa.gov/files/training_testing/testing/test_questions/par_questions.pdf

Test yourself in the game

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That's stuff everyone should know.