Definition
The defined portions that together make up a published instrument approach procedure (IAP). A standard IAP is divided into five segments: the feeder route, the initial approach segment, the intermediate approach segment, the final approach segment, and the missed approach segment. Each segment begins and ends at a named fix or specified point, and each has its own course, altitude, and obstacle clearance criteria designed to transition the aircraft safely from the en route environment down to the runway, or to a missed approach if the landing cannot be completed.
Plain English
An instrument approach is broken into named parts. Each part takes the aircraft one step closer to the runway, with its own track to fly and its own minimum altitude. Together they form a continuous path from cruise flight down to landing, with a built-in escape path if the landing has to be abandoned.
Context Anchor
Seen when reading an instrument approach chart or studying how an instrument approach is built and flown.
Derivation
A segment is simply a piece of something larger. The approach is split into pieces because each piece serves a distinct purpose — getting established, descending, lining up with the runway, and handling a go-around — and each needs its own protected airspace and altitude rules.
Why Pilots Care
Knowing the segments helps pilots manage speed, configuration, and navigation changes at the right times to fly the approach safely and compliantly.
Intuition Check
Do not think of segments as informal chunks of an approach. Here, segments are published parts of the procedure, each with a specific path, altitude requirement, and purpose.
Example Sentence 1
During the approach briefing, the pilot identified the initial, intermediate, and final segments and noted the minimum altitude for each.
Example Sentence 2
Each of the instrument approach procedure segments has its own protected airspace and minimum altitudes.