Aircraft systems and instrumentsQuestion 664 of 934

What type of electrical system do most aircraft have?

  1. A 110-volt alternating current system
  2. A 14-volt or 28-volt direct current system
  3. A 5-volt or 9-volt direct current system
  4. A 115-volt, 400-hertz alternating current system
Show answer

Correct answer: A 14-volt or 28-volt direct current system

A basic system has an alternator or generator, battery, master switch, bus bar, fuses or circuit breakers, voltage regulator, and ammeter.

Source: Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25C), Chapter 7: Aircraft Systems — Electrical System, page 190

Practice aircraft systems and instruments

Questions last reviewed: 18 October 2026