When does the Cockpit Voice Recorder (CVR) and Digital Flight Data Recorder (DFDR) stop automatically?

The Cockpit Voice Recorder (CVR) and Digital Flight Data Recorder (DFDR) are crucial safety devices in aviation, designed to capture and preserve critical flight data and cockpit audio. These recorders have specific functions for stopping their operations automatically based on the engine shut-down sequence.

The correct option states that both the CVR and DFDR automatically stop recording 5 minutes after the last engine is shut down. This time frame allows for a buffer period during which any final communications or critical data can still be captured, ensuring that the most up-to-date flight information is preserved even immediately following the completion of the flight. Recording until the last engine shutdown enhances the integrity of the flight data collected, providing the most comprehensive overview of the aircraft's final operations, which can be vital in the event of an investigation.

The other choices do not accurately reflect the timing or conditions under which the CVR and DFDR stop recording. For example, if the recording were to stop based on the first engine shutdown, important data from the second engine shutdown would be missed. Similarly, stopping recordings based on electrical power supply or a ground control switch position disruption could lead to a lack of crucial data during critical phases of aircraft operations.