Which of the following is NOT affected by the 30-minute information retention rule of cockpit voice recorders?

The choice indicating that events occurring before the last 30 minutes are not affected by the 30-minute information retention rule is correct. Cockpit voice recorders (CVRs) are designed to capture and store audio data from the cockpit, typically retaining only the most recent 30 minutes of recording. This means that any conversations or events that took place prior to that 30-minute window are automatically overwritten and are not retrievable.

Conversations involving crew members, information regarding air traffic control interactions, and details of emergency procedures all fall within the timeframe that the CVR retains. Therefore, any discussions or actions related to these aspects would be recorded only if they occurred within the last 30 minutes prior to any incident. Once this timeframe elapses, the recordings of these discussions become unavailable if they precede the 30-minute threshold.