Definition
Published instrument approach procedures developed by the FAA (or another approving authority) that specify the routes, altitudes, course guidance, and minimums a pilot must follow to descend safely from en route flight to a point near the runway when flying solely by reference to instruments. Each SIAP is depicted on an approach chart and is flown using ground-based or satellite-based navigation aids.
Plain English
The official, charted step-by-step procedures pilots follow to line up with and descend toward a runway when they cannot rely on seeing outside.
Context Anchor
Seen during approach planning, approach briefing, and when selecting an instrument approach for an airport.
Derivation
Standard means the procedure is officially published and uniform, so any qualified pilot can fly it the same way. Instrument means the procedure is designed to be flown using cockpit instruments rather than outside visual references. Approach refers to the transition from en route flight down toward the runway.
Why Pilots Care
Using the correct SIAP ensures a safe, standardized descent path that keeps the aircraft clear of terrain and obstacles in low visibility.
Intuition Check
SIAPs are not just any way of approaching an airport. They are specific published procedures with required paths, altitudes, and limits.
Example Sentence 1
After receiving the clearance, the pilot briefed the SIAP for runway 27, noting the final approach course, step-down altitudes, and decision altitude.
Example Sentence 2
During the briefing the crew compared the current weather to the requirements listed on the SIAPs.