Definition
The height above the runway touchdown zone, specified for a precision instrument approach, at which the pilot must have the required visual references to continue the approach to landing. If those references are not visible at this height, the pilot must immediately execute a missed approach.
Plain English
The exact height during a precision instrument approach where the pilot has to make a go/no-go choice: if the runway is in sight, land; if not, climb away and try again or go elsewhere.
Context Anchor
Seen on instrument approach procedures, especially precision approaches that guide the aircraft down toward the runway in poor visibility.
Derivation
Called 'decision' because it is the precise point at which the pilot must decide whether to continue or abandon the approach. 'Height' (rather than altitude) is used because it is measured above the runway touchdown zone, not above sea level.
Why Pilots Care
It is the last safe point to abandon an approach without visual confirmation, directly preventing controlled flight into terrain.
Grounding Statement
Picture descending through cloud toward a runway: Decision Height is the published point where you must either have the runway environment in sight or climb away.
Intuition Check
Decision Height does not mean any moment when the pilot feels ready to decide. It is a specific published height on the approach, and the required action at that point is controlled by the rules and what the pilot can see.
Example Sentence 1
On the ILS approach into runway 27, the captain called 'minimums' as the aircraft reached decision height and the runway lights came into view.
Example Sentence 2
At decision height the runway remained obscured by fog, so the crew executed the missed approach procedure.