ACS codes · General · Fundamentals of Electricity and Electronics
AM.I.A.K18 · Knowledge
Controlling devices, including switches and relays
Updated October 25, 2026 · element text from the FAA Aviation Mechanic ACS (FAA-S-ACS-1)
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What the ACS says
Controlling devices, including switches and relays.
A sample oral question on this element
“Why do the components in an aircraft electrical circuit need control devices?”
Study source: FAA-H-8083-30B (Aviation Maintenance Technician Handbook, General), chapter 12, pages 12-30, 12-31, 12-32, 12-33
If this code is on your test report
Your Airman Knowledge Test Report (AKTR) lists an ACS code for every knowledge area you missed on the written test. On the A&P oral, each of those codes adds one question to that section, on top of a minimum of four random questions (FAA Mechanic Test Generator FAQ). So if AM.I.A.K18 is on your AKTR, expect the examiner to ask about it. More on how codes turn into oral questions: A&P ACS codes: know your codes before the oral.
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