Definition
A controlled phase of flight in which the airplane loses altitude in a planned, deliberate manner, achieved by reducing power, lowering the pitch attitude, or both, while maintaining airspeed within prescribed limits.
Plain English
Descent is the part of a flight where the airplane is purposely going down to a lower altitude.
Context Anchor
Seen on phase-of-flight checklists, especially when preparing to leave level flight and move toward landing.
Derivation
From the Latin descendere, meaning 'to climb down' (de- 'down' + scandere 'to climb'). The aviation meaning keeps that original sense — moving downward in a controlled way.
Why Pilots Care
Proper descent planning ensures terrain clearance, fuel efficiency, and smooth transition into the approach and landing phases.
Intuition Check
Descent does not simply mean “falling.” In aviation, a descent is normally a planned, controlled move to a lower altitude; an unplanned loss of height is a separate problem.
Example Sentence 1
After reaching the top of cruise, the pilot ran the descent checklist and began a gradual descent toward the destination airport.
Example Sentence 2
A standard descent rate of 500 feet per minute keeps the aircraft within its normal operating limits.