When does the Cockpit Voice Recorder (CVR) operate continuously?

The Cockpit Voice Recorder (CVR) operates continuously during all phases of flight that involve active communication and operational activities by the flight crew. This includes the period from the start of checklist usage until the final checklist is completed.

During this time, critical communications, including discussions related to aircraft operations, decision-making processes, and any important back-and-forth between crew members, are recorded. This continuous operation ensures that important context and actions taken by the flight crew can be retrieved in the event of an incident or accident, maximizing the potential for understanding what transpired in the cockpit.

The other options don't accurately capture the continuous operational aspect of the CVR. For instance, while engine operations and pre-flight activities are crucial, they do not encompass the complete spectrum of recording that occurs through active checklist usage until the flight transitions into a stable phase of flight where such recordings may be less critical.