Mixed Deck — All AET Topics Flashcards
100 cards from real AET practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 20 Mixed Deck — All AET Topics flashcards as text
In an Inertial Reference System (IRS), what sensors are used to measure angular rate?
Answer: Ring laser gyroscopes or fiber optic gyroscopes
Modern IRS units use ring laser gyroscopes (RLGs) or fiber optic gyroscopes (FOGs) to measure angular rate without moving parts.
How many discrete digital output values can a 12-bit ADC produce?
Answer: 4,096
A 12-bit ADC can represent 2^12 = 4,096 discrete digital values, ranging from 0 to 4,095.
When an AET completes an avionics repair, the return-to-service entry must be signed by a person holding which certificate?
Answer: Airframe and Powerplant Mechanic or Repairman
Only an FAA-certificated Airframe and Powerplant (A&P) mechanic, Repairman, or authorized repair station representative may approve an aircraft for return to service after maintenance.
Which of the following correctly describes 'Safety Wire' (safetying) application on avionics rack mounting hardware?
Answer: Wire is threaded so that rotation of the fastener in the loosening direction tightens the wire
Safety wire must be installed so that the fastener cannot rotate in the loosening direction without pulling the wire taut, providing positive locking.
Why is it important to regularly calibrate test equipment used in aircraft maintenance?
Answer: To ensure the equipment provides accurate and reliable measurements
Regular calibration of test equipment is essential in aircraft maintenance to guarantee that all measurements taken are consistently accurate and reliable. Uncalibrated equipment can provide erroneous readings, leading to misdiagnosis of issues or incorrect adjustments, which could compromise aircraft safety and operational integrity. Calibration ensures that the tools perform within specified tolerances, maintaining the highest standards of precision.
What is the typical voltage output of an aircraft's 28V DC bus system when fully regulated?
Answer: 27.5–28.5 volts
A regulated 28V system operates between approximately 27.5 and 28.5 volts to properly charge 24V batteries while powering the aircraft's electrical loads.
Which organization is primarily responsible for setting aviation safety regulations in the United States?
Answer: Federal Aviation Administration (FAA)
The Federal Aviation Administration (FAA) is the primary governmental authority responsible for regulating all aspects of civil aviation in the United States. Its mission includes ensuring the safety of air travel by setting and enforcing aviation safety regulations and standards.
An FAA-certificated avionics technician may legally perform a major alteration on a certificated aircraft only if the work is performed in accordance with:
Answer: FAA-approved data such as an STC, AD, or FAA-approved engineering order
Major alterations must be performed in accordance with FAA-approved data, which includes STCs, ADs, FAA-approved engineering orders, or other data acceptable to the FAA.
During an ILS approach, a glideslope pointer above center on the ADI/flight director indicates the aircraft is:
Answer: Below the glideslope — fly up
A glideslope deviation pointer above center means the glideslope beam is above the aircraft, so the aircraft is below the glideslope and must climb (fly up) to intercept it.
What is the primary advantage of ARINC 664 (AFDX — Avionics Full-Duplex Switched Ethernet) over ARINC 429 in modern aircraft?
Answer: Vastly higher bandwidth and bidirectional data flow on a single connection
ARINC 664/AFDX provides 10/100 Mbps full-duplex bandwidth, supporting bidirectional communication over a single connection — a dramatic improvement over ARINC 429's 12.5 kbps or 100 kbps unidirectional bus. It is used in aircraft such as the Airbus A380 and Boeing 787.
Which type of fire extinguisher is approved for use on an avionics bench fire involving energized electrical equipment?
Answer: Class C dry chemical or CO2 extinguisher
Class C extinguishers (CO2 or dry chemical) are rated for energized electrical equipment fires because they use non-conductive extinguishing agents.
What is the primary advantage of nickel-cadmium (NiCd) batteries used in turbine-powered aircraft over lead-acid batteries?
Answer: More stable voltage during discharge and better high-current performance
NiCd batteries maintain a relatively flat discharge voltage and deliver high cranking currents reliably, making them preferred for turbine engine starts and emergency power in transport aircraft.
Which logic gate produces a HIGH output only when all inputs are HIGH?
Answer: AND gate
An AND gate output is HIGH only when every input is simultaneously HIGH.
Within a microprocessor, which unit is responsible for performing arithmetic and logic operations?
Answer: ALU (Arithmetic Logic Unit)
The ALU executes all arithmetic (addition, subtraction) and logical (AND, OR, NOT) operations in a microprocessor.
When installing a D-sub connector backshell on an avionics cable, the primary purpose of the backshell's strain relief is to:
Answer: Prevent mechanical stress on individual conductor solder joints or crimps at the connector pins
The backshell strain relief clamps the cable jacket to transfer axial and bending loads to the cable jacket rather than to the individual pin solder joints or crimp connections.
What is a 'ferry permit' and what documentation is associated with it?
Answer: A Special Flight Permit allowing an unairworthy aircraft to fly to a repair facility under specific conditions
A Special Flight Permit (ferry permit) under 14 CFR 21.197 allows an aircraft that does not meet airworthiness standards to fly under specific approved conditions to reach a repair facility.
Emergency Locator Transmitters (ELTs) required under TSO-C126b operate on which frequency?
Answer: 406 MHz (with optional 121.5 MHz homing)
Modern 406 MHz ELTs transmit a digital coded burst processed by COSPAS-SARSAT satellites, and typically also transmit on 121.5 MHz for local homing.
When analyzing data from an avionics test set, which of the following is a crucial aspect to verify?
Answer: The accuracy of the measurements and comparison with expected values
When analyzing data from an avionics test set, the most crucial aspect is to verify the accuracy of the measurements and compare them with expected values or specifications. This ensures that the aircraft's electronic systems are functioning within their designed parameters and meet safety and performance standards. Any deviation from expected values indicates a potential fault that requires further investigation and corrective action.
What type of memory is typically used to store the boot firmware in an avionics Line Replaceable Unit (LRU)?
Answer: Flash (EEPROM)
Flash (EEPROM) is non-volatile and retains firmware without power, making it standard for avionics LRU boot code storage.
A SATCOM system on an aircraft provides communication primarily via:
Answer: Geostationary or LEO satellites
SATCOM uses geostationary (e.g., Inmarsat) or low Earth orbit satellites to relay voice and data communications globally, including over oceans.