Definition
An autopilot function that, when activated, automatically descends the aircraft to a lower altitude without further pilot input. It is typically used in pressurization emergencies where the flight crew may be incapacitated, bringing the aircraft to a breathable altitude as quickly as the system allows.
Plain English
A button or automatic feature on the autopilot that, once triggered, flies the aircraft down to a safer, lower altitude on its own — usually because the people on board may not be able to do it themselves.
Context Anchor
Seen in discussions of high-altitude, pressurized aircraft, emergency procedures, and aircraft automation.
Why Pilots Care
Enables rapid descent without pilot input to prevent hypoxia and reach breathable altitudes quickly.
Grounding Statement
If the cabin loses pressure high above the ground and the crew does not act quickly, the aircraft may be designed to start a safe descent on its own.
Intuition Check
Do not read “automated” as meaning the emergency is fully solved. It only means the aircraft can begin the descent without a fresh pilot command; pilots still need to monitor, communicate, and manage the situation if able.
Example Sentence 1
After the cabin altitude warning sounded, the pilot activated the automated emergency descent and the aircraft began descending toward 15,000 feet on its own.
Example Sentence 2
In simulator training, crews practiced responding to scenarios where the automated emergency descent engaged due to pilot incapacitation.