NEWEST NCATT AET AND AEIT
ENDORSEMENT (EMI, GROUNDING
,BONDING ,TSO,PMO,PMA & AIRCRAFT
WIRING) ACTUAL EXAM 2026/2027
ACCURATE TEST APPROVED QUESTIONS
AND CORRECT DETAILED ANSWERS
(COMPLETE VERIFIED SOLUTIONS) LATEST
UPDATED VERSION |GUARANTEED PASS
A+
1. What is the primary mechanism by which EMI affects
avionics systems?
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• A) Thermal heating of conductors
• B) Unwanted coupling of electromagnetic energy into
sensitive circuits
• C) Galvanic corrosion of connectors
• D) Electrostatic discharge from human touch
Answer: B
Rationale: EMI occurs when electromagnetic energy from a
source couples (via radiated or conducted paths) into a victim
circuit, causing noise, false data, or malfunction.
2. Which frequency range is most susceptible to radiated EMI
from aircraft communication antennas?
• A) 10 Hz – 1 kHz
• B) 100 kHz – 30 MHz
• C) 30 MHz – 1 GHz
• D) Above 10 GHz
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Answer: C
Rationale: VHF/UHF comm (118–137 MHz, 225–400 MHz)
and navigation systems operate in 30 MHz–1 GHz, where
radiated coupling is highly efficient.
3. Scenario: A technician finds that turning on the weather
radar causes the GPS to lose position. This is most likely:
• A) Conducted EMI via power lines
• B) Radiated EMI from radar harmonics
• C) Ground loop interference
• D) TSO incompatibility
Answer: B
Rationale: Weather radar (pulsed, high power) radiates
strong fields that can overload sensitive GPS front-ends,
especially if harmonic content falls near GPS frequencies
(1.575 GHz).
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4. Which shielding effectiveness improvement would best
reduce radiated EMI at 400 MHz?
• A) Increasing conductor gauge
• B) Using aluminum foil with 90% coverage
• C) Applying ferrite beads only
• D) Using a solid copper shield with <5% openings
Answer: D
Rationale: Shield effectiveness at RF depends on conductivity,
thickness, and low porosity. Solid copper provides high
attenuation.
5. What is the dominant coupling mechanism for EMI between
two parallel wires in a bundle?
• A) Radiated
• B) Inductive and capacitive
• C) Galvanic
• D) Common impedance