Definition
An autopilot mode found on some advanced aircraft that, when activated, automatically commands the aircraft to descend rapidly to a lower, breathable altitude without further pilot input. It is designed for situations such as cabin depressurization, where the crew may be incapacitated or hypoxic. The mode typically sets a target altitude, reduces thrust, and commands a steep descent at a safe airspeed.
Plain English
A setting on the autopilot that, when switched on, makes the aircraft drop down to a lower altitude on its own, in case the pilots can't fly the plane themselves.
Context Anchor
Seen in discussions of advanced autopilots, pressurized aircraft, and emergency automation features.
Derivation
Mode comes from the Latin modus, meaning a manner or way of doing something. In aircraft systems, a mode is the way a system is currently operating, so Emergency Descent MODE means the aircraft automation is operating in its emergency-descent way.
Why Pilots Care
It enables a swift descent to a breathable altitude with minimal pilot workload, helping prevent hypoxia while the crew handles the underlying emergency.
Grounding Statement
Picture a high-altitude airplane with a cabin-pressure problem: the safest first move may be to get lower quickly while keeping the descent controlled.
Intuition Check
Do not read this as just any emergency descent flown by a pilot. Here, MODE means a specific automated operating state of the aircraft system, available only on aircraft equipped with that feature.
Example Sentence 1
After the cabin pressure warning sounded, the autopilot engaged Emergency Descent Mode and the aircraft began a rapid descent toward 15,000 feet.
Example Sentence 2
The autopilot remained in emergency descent mode until the aircraft reached a safe altitude and the pilot took over manually.