If the flight deck door is opened during takeoff, what should the cabin crew do?

In the scenario where the flight deck door is opened during takeoff, the cabin crew should remain seated and stay alert for potential threats because their primary focus should be on ensuring the safety and security of all passengers and the aircraft. This is a critical time during the flight where the crew must assess the situation carefully, as an open flight deck door poses significant risks. By staying seated, the cabin crew can observe any unusual behavior or activity and be ready to respond if needed.

While assisting the flight crew and attempting to close the door, although they might appear to be logical responses, they may place the cabin crew in unnecessary danger or divert their attention from the overall safety of the cabin. Evacuating the aircraft at this stage is also typically not feasible or safe, as it may lead to chaos during a critical phase of the flight like takeoff. Therefore, maintaining a position of readiness and awareness is the appropriate course of action for the cabin crew in this scenario.