| 释义 |
standard instrument arrival standard instrument arrivalA designated IFR arrival route liking a significant point, normally on ATS route, with a point from which a published instrument approach procedure can be commenced (ICAO). When necessary or where an operational advantage is obtained, arrival routes from the en route phase to the fix or facility used in the procedure are published. When arrival routes are published, the width of the associated area decreases from the “en route” value until the “initial approach” value with the convergence angle of 30° on each side of the axis. The convergence begins at 25 NM before the initial approach fix (IAF) if the length of the arrival route is greater than or equal to 25 NM. It begins at the starting point of the arrival route if the length of the arrival route is less than 25 NM. The arrival route normally ends at the initial approach fix. Omnidirectional or sector arrivals can be provided taking into account the minimum sector altitude. IFR means instrument flight rules, and ATS stands for air traffic services. |