What device is used to automatically erase older recordings in a cockpit voice recorder?

The device responsible for automatically erasing older recordings in a cockpit voice recorder is timer circuitry. This system is designed to manage the storage capacity of the voice recorder by ensuring that only the most recent recordings are retained, thus optimizing performance and maintaining essential flight data privacy protocols.

Timer circuitry functions by monitoring the length of time recordings have been stored. When a certain time limit is reached or the memory reaches capacity, the circuitry activates the automatic deletion process for the oldest recordings, allowing new audio data to be captured without manual intervention. This ensures that recordings from a flight are retained only for a specific period, complying with regulations while also safeguarding critical flight safety information.

In contrast, the audio control panel and data recorder module serve different purposes in the cockpit; the audio control panel manages audio inputs and outputs, while the data recorder module deals with various flight data aspects. An erasure mechanism could generally refer to a manual or separate system for deleting recordings but isn't specifically the built-in timed function that manages the automatic process of older data removal in voice recorders.