During a sterile cockpit period, which activity is forbidden for cabin crew?

The sterile cockpit period is a crucial time during flight operations, defined as the time when the aircraft is below a certain altitude during takeoff and landing, typically below 10,000 feet. During this time, cabin crew are required to focus solely on safety-related duties and to minimize distractions to the flight crew, thereby ensuring that all attention is directed towards managing the critical phases of flight.

Entering the flight deck during the sterile cockpit period is forbidden because it can divert the flight crew's attention away from their primary responsibilities. The cockpit must remain undistracted to allow pilots to perform their duties safely without interruptions from cabin crew. This restriction is designed to promote the highest levels of safety during some of the most critical phases of flight, where any form of distraction can potentially lead to misunderstandings or errors.

In contrast, taking passenger orders, monitoring cabin safety, and calling the flight crew are all activities that can be performed within the framework of ensuring a safe and comfortable environment for passengers without infringing upon the sterile cockpit rule. These tasks focus on maintaining safety and service for passengers while the pilots need to concentrate on flying the aircraft without additional distractions.