Airworthy Prep
Get A&P

Subject area H of 15

Aircraft Instrument Systems

5-10% of the A&P Airframe test, about 5 to 10 of the 100 questions. The FAA's test standard lists 24 knowledge elements and 5 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.H.K1Annunciator indicating systems and the meaning of warning, caution, and advisory lights.
  • AM.II.H.K2Magnetic compass inspection and operation.
  • AM.II.H.K3Magnetic compass swinging procedures.
  • AM.II.H.K4Pressure indicating instruments.
  • AM.II.H.K5Temperature indicating instruments.
  • AM.II.H.K6Position indication sensors and instruments.
  • AM.II.H.K7Gyroscopic instruments.
  • AM.II.H.K8Direction indicating instruments.
  • AM.II.H.K9Instrument vacuum and pneumatic systems.
  • AM.II.H.K10Pitot-static system.
  • AM.II.H.K11Fuel quantity indicating systems.
  • AM.II.H.K12Instrument range markings.
  • AM.II.H.K13Electronic displays.
  • AM.II.H.K14Electrostatic sensitive devices.
  • AM.II.H.K15Built-in test equipment.
  • AM.II.H.K16Electronic flight instrument system.
  • AM.II.H.K17Engine indication and crew alerting system.
  • AM.II.H.K18Head-up displays (HUDs).
  • AM.II.H.K1914 CFR parts 43 and 91 requirements for static system leak checks.
  • AM.II.H.K20Instrument limitations, conditions, and characteristics.
  • AM.II.H.K21Angle of attack and stall warning systems.
  • AM.II.H.K22Takeoff and landing gear configuration warning systems.
  • AM.II.H.K23Aircraft bonding and protection.
  • AM.II.H.K24Instrument or instrument panel removal and installation.

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

  • AM.II.H.R1Use of pressurized air and water during maintenance or cleaning of aircraft instrument systems.
  • AM.II.H.R2Actions in response to a reported intermittent warning or caution annunciator light illumination.
  • AM.II.H.R3Performing maintenance on equipment identified as electrostatic-sensitive.
  • AM.II.H.R4Handling of mechanical gyros or instruments containing mechanical gyros.
  • AM.II.H.R5Performing a pitot/static system test.

Try a sample question

Aircraft Instrument Systems ยท AM.II.H.K20

A pilot reports that after a long cruise at one altitude, the analog altimeter was slow to follow a rapid descent, then caught up once the airplane leveled off. The static system tests satisfactorily. Which altimeter limitation explains this?

Practice all of aircraft instrument systems

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

See the courseFree mock test