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Electrical Systems & Avionics Flashcards

7 cards from real ACS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Electrical Systems & Avionics flashcards as text

  1. What is the primary function of a static inverter in an aircraft?

    Answer: To convert DC power to AC power for avionics and instruments

    A static inverter converts aircraft DC power (from the battery or generator) into AC power required by certain avionics and instruments.

  2. When performing a bonding check on an aircraft, what maximum resistance is typically acceptable between two airframe components?

    Answer: 0.003 ohm

    FAA AC 43.13-1B specifies that bonding connections should have resistance not exceeding 0.003 ohm (3 milliohms) for effective static discharge and EMI protection.

  3. An ADF receiver bearing pointer rotates continuously and does not settle on a station. What is the most likely cause?

    Answer: A faulty ADF loop antenna

    A defective loop antenna causes the bearing pointer to continuously rotate since the system cannot determine directional signal phase difference.

  4. What does a transponder's MODE C capability provide to ATC?

    Answer: Pressure altitude information encoded with the transponder reply

    Mode C transponders encode pressure altitude data (from the aircraft's encoding altimeter) with each reply, allowing ATC to display altitude alongside the target.

  5. What is the purpose of a current limiter (fuse link) installed in series with an aircraft alternator?

    Answer: To protect the main bus wire from excessive current if the alternator fails internally

    A current limiter protects the heavy alternator output cable from damage in the event of an alternator internal short circuit.

  6. Which wire gauge would be correct for a 20-ampere circuit run 15 feet in a non-bundle, non-conduit installation?

    Answer: 14 AWG

    Per FAA AC 43.13-1B wire sizing charts, a 20-ampere circuit at 15 feet requires 14 AWG wire to limit voltage drop to 1 volt.

  7. A DME indicator shows distance but the reading fluctuates erratically. Which component is most likely at fault?

    Answer: The DME antenna

    An intermittent DME antenna connection causes fluctuating interrogation signal strength, resulting in erratic distance readings.