During single display operation, how long can the SD or STATUS page be displayed on the lower DU?

The correct answer reflects the specific operational limitation for the display of the System Display (SD) or STATUS page during single display operation on the A320. In single display operation, which can occur under certain conditions such as a failure of one of the display units, the SD or STATUS page has a set timeout period to ensure efficient management of screen real estate and focus on critical information.

The duration of 3 minutes represents the designed functionality to provide pilots with sufficient time to review important statuses or messages displayed during an abnormal operation. After this time period elapses, the system will automatically revert to the primary flight display information to maintain situational awareness. This is an important factor in the cockpit environment, where timely and accurate information is crucial for safe operation.

Understanding this operational limitation helps ensure that pilots are aware of how long critical information is guaranteed to be visible when relying on a single display, thus optimizing their ability to respond to various flight conditions without losing essential situational awareness.