01. Maximum 5 Segments
As required by local conditions an instrument approach procedure may be designed to consist of a maximum of 5 phases or — as ICAO defines it — segments. The following table indicates where these segments can be found.
Approach segment table
| SEGMENT | BEGINS AT |
|---|---|
| 1. Arrival | Airway |
| 2. Initial | Initial Approach fix (IAF) |
| 3. Intermediate | Intermediate approach fix (IF) |
| 4. Final (Precision appr) | Final approach point (FAP = GP intercept) |
| Final (Non-precision appr) | Final Approach Fix (FAF)* |
| 5. Missed approach (Precision appr) | Reaching DA or DH |
| Missed approach (Non-precision appr) | Published missed Approach point (MAPt) |
Typical approach
A typical approach would look like this:
Note on FAF
If the facility providing track guidance is located at the aerodrome and if the FAF can not be suitably fixed (e.g. single NDB approach) ICAO assumes the final approach segment to begin as soon as the aircraft is established on the final approach track.
02. Survey of the Operational Limitations for Each Approach Segment
For each approach segment operational limitations have been established. They have all been discussed in the paragraphs before. On the following page you will find a chart of a typical ILS (Precision approach) and a Non-precision approach procedure.
It is a survey of the combination of approach segments and limitations.