AET Avionics Systems 4 — Questions and Answers
Question 1: What is the purpose of the Aircraft Communications Addressing and Reporting System (ACARS)?
- Provide cabin passenger Wi-Fi
- Transmit digital data messages between aircraft and ground stations (Correct answer)
- Encrypt cockpit voice communications
- Control engine thrust automatically
Correct answer: Transmit digital data messages between aircraft and ground stations
ACARS is a digital datalink system that transmits short messages between aircraft and airline operations or ATC ground stations.
Question 2: In avionics, what does 'LRU' stand for?
- Local Radio Unit
- Line Replaceable Unit (Correct answer)
- Low Range Ultrasonics
- Lateral Reference Uplink
Correct answer: Line Replaceable Unit
LRU stands for Line Replaceable Unit, a modular avionics component designed for quick replacement on the flight line without depot-level maintenance.
Question 3: Which system provides accurate altitude information by measuring atmospheric pressure?
- Radio Altimeter
- Air Data Computer (ADC) (Correct answer)
- GPS height function
- Inertial Reference System
Correct answer: Air Data Computer (ADC)
The Air Data Computer (ADC) converts static pressure measurements from pitot-static probes into calibrated altitude, airspeed, and Mach data.
Question 4: What is the function of a Flight Data Recorder (FDR) mandatory parameter — 'pitch attitude'?
- Record nose-up or nose-down aircraft rotation about the lateral axis (Correct answer)
- Record bank angle about the longitudinal axis
- Record heading changes about the vertical axis
- Record engine torque values
Correct answer: Record nose-up or nose-down aircraft rotation about the lateral axis
Pitch attitude records rotation about the lateral (wing-to-wing) axis, indicating nose-up or nose-down orientation during flight.
Question 5: What technology does ADS-B use to broadcast an aircraft's position?
- Secondary surveillance radar interrogation
- GPS-derived position transmitted via 1090 MHz transponder (Correct answer)
- ILS glide slope signal encoding
- ACARS HF radio uplink
Correct answer: GPS-derived position transmitted via 1090 MHz transponder
ADS-B Out uses GPS position data broadcast autonomously on 1090 MHz via Mode S transponder without requiring radar interrogation.
Question 6: Which of the following correctly describes a Cockpit Voice Recorder (CVR) recording duration requirement under current FAA regulations for newly certified transport aircraft?
- 30 minutes
- 1 hour
- 2 hours (Correct answer)
- 4 hours
Correct answer: 2 hours
Current FAA regulations require CVRs on newly certified transport category aircraft to retain the last 2 hours of audio.
Question 7: What is the role of a Distance Measuring Equipment (DME) transponder ground station?
- Transmit VOR course guidance
- Reply to aircraft interrogation pulses to allow slant-range distance computation (Correct answer)
- Broadcast weather data in digital format
- Provide ILS glidepath signal
Correct answer: Reply to aircraft interrogation pulses to allow slant-range distance computation
The DME ground transponder receives interrogation pulses from the aircraft, replies after a fixed delay, and the aircraft computes slant-range distance from the round-trip time.
AET Avionics Systems 4
What is the purpose of the Aircraft Communications Addressing and Reporting System (ACARS)?