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Subject area I of 15

Communication and Navigation Systems

5-10% of the A&P Airframe test, about 5 to 10 of the 100 questions. The FAA's test standard lists 21 knowledge elements and 6 risk management elements for this area. Here is every one, plus sample questions to try.

What the FAA tests

From the aviation mechanic test standard, FAA-S-ACS-1.

Knowledge: what you must know

  • AM.II.I.K1Radio operating principles.
  • AM.II.I.K2Radio components.
  • AM.II.I.K3Antenna, static discharge wicks, and avionics identification, inspection, and mounting requirements.
  • AM.II.I.K4Interphone and intercom systems.
  • AM.II.I.K5Very high frequency (VHF), high frequency (HF), and SATCOM systems.
  • AM.II.I.K6Aircraft Communication Addressing and Reporting System (ACARS) theory, components, and operation.
  • AM.II.I.K7Emergency locator transmitter (ELT).
  • AM.II.I.K8Automatic direction finder (ADF).
  • AM.II.I.K9VHF omnidirectional range (VOR) theory, components, and operation.
  • AM.II.I.K10Distance measuring equipment (DME) theory, components, and operation.
  • AM.II.I.K11Instrument landing system (ILS) theory, components, and operation.
  • AM.II.I.K12Global positioning system (GPS) theory, components, and operation.
  • AM.II.I.K13Traffic collision avoidance system (TCAS), theory, components, and operation.
  • AM.II.I.K14Weather radar.
  • AM.II.I.K15Ground proximity warning system (GPWS) theory, components, and operation.
  • AM.II.I.K16Autopilot theory, components, and operation.
  • AM.II.I.K17Auto-throttle theory, components, and operation.
  • AM.II.I.K18Stability augmentation systems (SAS) (Rotorcraft).
  • AM.II.I.K19Radio altimeter (RA) theory, components, and operation.
  • AM.II.I.K20Automatic Dependent Surveillance-Broadcast (ADS-B) theory, components, and operation.
  • AM.II.I.K21Transponder/encoder system.

Risk management: hazards you must be able to spot and manage

  • AM.II.I.R1ELT testing procedures.
  • AM.II.I.R2Performing maintenance on high power/high frequency systems (e.g., weather radar and SATCOM).
  • AM.II.I.R3Wire harness routing.
  • AM.II.I.R4Mounting antennas.
  • AM.II.I.R5Electro-static discharge.
  • AM.II.I.R6Working around live electrical systems.

Try a sample question

Communication and Navigation Systems ยท AM.II.I.K5

A pilot reports that the airplane's VHF communication radio will not tune some frequencies. In what frequency range do VHF aircraft communication radios operate?

Practice all of communication and navigation systems

The full course has questions on every element listed here, with an explanation and FAA source for each.

See the courseFree mock test