Definition
A descent or climb performed at a fixed, unchanging vertical speed, typically expressed in feet per minute (fpm) on the vertical speed indicator. The pilot adjusts pitch and power so the aircraft gains or loses altitude at the same rate throughout the maneuver.
Plain English
Climbing or descending at a steady number of feet per minute, instead of speeding up or slowing down vertically along the way.
Context Anchor
Seen when entering and holding straight climbs or descents by reference to flight instruments.
Derivation
Constant comes from a Latin idea meaning “standing firm” or “unchanging.” Rate means an amount measured over time. Together, constant rate means the amount of altitude change per minute stays steady.
Why Pilots Care
Allows predictable altitude changes that fit planned descent profiles or climb requirements without overshooting assigned altitudes.
Intuition Check
Constant rate does not mean constant airspeed, constant pitch, or constant power. Here it means the airplane’s climb or descent per minute stays steady.
Example Sentence 1
The instructor asked for a constant rate descent of 500 feet per minute from cruise altitude down to the initial approach fix.
Example Sentence 2
Maintaining a constant rate during the descent let the aircraft reach the next altitude exactly on time.