IA Avionics & Electrical Systems Inspection 2 — Questions and Answers
Question 1: What does an IA verify when inspecting the aircraft's master switch and alternator system during an annual?
- That the master switch is a red guard-covered toggle only
- That the alternator output voltage and current meet manufacturer specifications and that the warning light functions (Correct answer)
- That the alternator belt tension is within torque specification
- That the alternator output is limited to 28 volts for all aircraft types
Correct answer: That the alternator output voltage and current meet manufacturer specifications and that the warning light functions
Annual inspection of the charging system includes verifying that the alternator charges at the correct voltage, delivers adequate current, and that the low-voltage warning indication works properly.
Question 2: During an annual inspection, an IA finds that an avionics unit was installed without an STC. What is the correct action?
- Approve the aircraft for return to service if the unit is functioning correctly
- Disapprove the aircraft for return to service and document the unapproved installation (Correct answer)
- Issue a temporary approval pending STC research
- Remove the unit and approve the aircraft without the avionics item
Correct answer: Disapprove the aircraft for return to service and document the unapproved installation
An avionics installation without proper approval (STC or field approval) is an unapproved alteration, and the IA must disapprove the aircraft for return to service and document the deficiency.
Question 3: What is the ELT inspection requirement that an IA must verify during an annual?
- ELT must be replaced every 2 years regardless of battery condition
- ELT battery must be replaced when 50% of useful life is consumed, or after 1 cumulative hour of use, per 14 CFR 91.207 (Correct answer)
- ELT operational test must be conducted by a certified avionics shop only
- ELT must be removed and bench-tested every annual inspection
Correct answer: ELT battery must be replaced when 50% of useful life is consumed, or after 1 cumulative hour of use, per 14 CFR 91.207
14 CFR 91.207 requires ELT batteries to be replaced when 50% of the battery's useful life (or shelf life) is consumed or after 1 hour of cumulative use.
Question 4: An IA inspects the aircraft's stall warning system and finds it inoperative. Under what condition could the aircraft be approved for return to service?
- The aircraft may be approved if the owner signs a statement accepting the inoperative stall warning
- Only if the inoperative item is listed on an approved Minimum Equipment List (MEL) or the stall warning is not required by the TCDS (Correct answer)
- The aircraft must have the stall warning repaired before any approval
- The stall warning can be deferred for 30 days per the FAA deferral program
Correct answer: Only if the inoperative item is listed on an approved Minimum Equipment List (MEL) or the stall warning is not required by the TCDS
An inoperative stall warning system may be legal if the aircraft's TCDS or an approved MEL permits it to be deferred; otherwise it is an airworthiness defect.
Question 5: What does an IA look for when inspecting aircraft antenna mounts during an annual?
- That all antennas are painted to match the aircraft color scheme
- Corrosion at the mount, cracked radomes, loose mounting hardware, and proper bonding to the airframe (Correct answer)
- That antenna length matches frequency specifications for the installed radio
- That all antennas are vertical polarization type
Correct answer: Corrosion at the mount, cracked radomes, loose mounting hardware, and proper bonding to the airframe
Antenna mount inspection focuses on structural security, corrosion at the mount plate, and proper electrical bonding to ensure the antenna functions correctly and doesn't create a structural weak point.
Question 6: During an annual, the IA checks the aircraft's lighting system. Which light is required to be inspected for proper operation on a VFR day-only aircraft?
- No lights are required for a VFR day-only aircraft, so none need inspection
- Position (navigation) lights, since they are required for night VFR and must be functional for airworthiness
- Rotating beacon only, as it is required during all engine operations at many airports
- Both position lights and anti-collision lights must be inspected per Appendix D (Correct answer)
Correct answer: Both position lights and anti-collision lights must be inspected per Appendix D
14 CFR Part 43 Appendix D requires inspection of all lighting equipment including position and anti-collision lights as part of the annual inspection scope.
IA Avionics & Electrical Systems Inspection 2
What does an IA verify when inspecting the aircraft's master switch and alternator system during an annual?