Which power source powers the cockpit voice recorder?

• A. DC electrical power is applied to the aircraft
• B. External power is available
• C. The APU is running
• D. The battery is charged

Answer: (A)

Power for the cockpit voice recorder comes from the aircraft’s DC electrical system. When the airplane’s electrical system is powered, the CVR is fed from the main DC power distribution (typically 28 V DC). External power or an APU may supply the aircraft’s electrical system, but the CVR itself is powered by that aircraft-wide DC power, not directly by the APU or by a separate battery. The onboard battery mainly supports starting and short-term backups for other systems, not the normal CVR power in flight.