Definition
The lowest altitude to which a pilot may descend on an instrument approach unless the required visual references for the intended runway are in sight and the aircraft is in a position to land using normal maneuvers. On a non-precision approach this is the Minimum Descent Altitude (MDA); on a precision or approach with vertical guidance, it is the Decision Altitude (DA) or Decision Height (DH).
Plain English
The lowest you are allowed to go on an instrument approach without seeing the runway environment. If you reach this altitude and still can't see what you need to land safely, you have to go around.
Context Anchor
Seen in instrument approach and landing minimums discussions, and on instrument approach charts before beginning an approach to land in poor weather.
Derivation
“Descent” comes from a Latin root meaning “to climb down.” “Minimum” comes from Latin meaning “smallest.” Together, the phrase points to the lowest allowed point in the descent, not just a low point that happens during the approach.
Why Pilots Care
It sets the hard limit for continuing an approach versus executing a missed approach, directly affecting safety and regulatory compliance.
Intuition Check
Do not read “descent minimum” as a suggested target or a normal descent setting. In this context, it means a published lower limit: you may not go below it unless the visual conditions needed for landing are met.
Example Sentence 1
We reached the descent minimum without seeing the runway, so I called the missed approach and started the climb.
Example Sentence 2
She checked the approach plate and confirmed the descent minimum before beginning the final descent.