What is the maximum altitude for single pack operation?

The maximum altitude for single pack operation is indeed 31,000 feet. This limit is important because it ensures that the aircraft can maintain a safe and comfortable cabin environment while still allowing for efficient operation of the environmental control system. When the aircraft is operating at altitudes above this threshold with only one pack, there may not be sufficient air flow to effectively pressurize and cool the cabin, which could lead to discomfort for passengers and crew.

Understanding pack operation is essential for pilots and crew members, as they may need to respond to different operational scenarios, such as equipment failure or engine-out situations. The limitation of 31,000 feet helps to maintain safety and comfort on board, ensuring a reliable performance of the air conditioning and pressurization system even when operating under reduced capacity.