Which of the following statements regarding cockpit voice recorders (CVR) is true?

The statement about cockpit voice recorders (CVR) that reflects the correct understanding is that a CVR may be disabled during flight by the Pilot-In-Command. This capability is sometimes necessary to manage situations where the recording may not be needed or could potentially interfere with safety operations. It allows the Pilot-In-Command, who bears ultimate responsibility for the safe operation of the aircraft, to make decisions that they deem necessary in the moment.

Understanding the broader regulations, while CVRs are designed to capture important audio data during flights for safety investigations, there are scenarios where a pilot may have the discretion to disable the device in the interest of operational safety or cockpit management. This flexibility is an important aspect of pilot authority and operational safety protocols.

In contrast, the other options present stipulations or scenarios that differ from the established regulations: a CVR cannot be disabled indiscriminately during flight for data preservation, erasure of the Flight Data Recorder (FDR) is generally subject to strict regulations, and while a captain does have operational leeway in emergencies, the specifics of the laws governing CVR are more focused on the recording and data capture responsibilities than on rule deviations.