Nonprecision localizer series#

It begins at an IAF and ends at the intermediate approach segment or intermediate fix (IF). Initial approach segment: This segment provides a method for aligning the aircraft with the intermediate or final approach segment and to permit descent during the alignment.Feeder routes: A route for aircraft to proceed from the en route structure to the IAF, which includes the course and bearing to be flown, the distance, and the minimum altitude.GNSS technology allows, at least theoretically, to create instrument approaches to any point on the Earth's surface (whether on land or water) consequently, there are nowadays examples of water aerodromes (such as Rangeley Lake Seaplane Base in Maine, United States) that have GNSS-based approaches.Īn instrument approach procedure may contain up to five separate segments, which depict course, distance, and minimum altitude. asphalt, gravel, turf, ice) runways (and those on aircraft carriers). : 4–9, 4–11, 4–19, 4–20, 4–41īefore satellite navigation (GNSS) was available for civilian aviation, the requirement for large land-based navigation aid (NAVAID) facilities generally limited the use of instrument approaches to land-based (i.e. Finally, the chart depicts the missed approach procedures in plan and profile view, besides listing the steps in sequence. NPAs depict the MDA while a PA shows both the decision altitude (DA) and decision height (DH). A cross depicts the final approach fix (FAF) altitude on NPAs while a lightning bolt does the same for PAs. Minimum, maximum and mandatory altitudes are depicted in addition to the minimum safe altitude (MSA) for emergencies. A communication strip on the chart lists frequencies in the order they are used. : 981–982 The chart name reflects the primary navigational aid (NAVAID), if there is more than one straight-in procedure or if it is just a circling-only procedure. Each procedure chart uses a specific type of electronic navigation system such as an NDB, TACAN, VOR, ILS/ MLS and RNAV. Besides depicting topographic features, hazards and obstructions, they depict the procedures and airport diagram. IAP charts are aeronautical charts that portray the aeronautical data that is required to execute an instrument approach to an airport. PAs and APVs are flown to a decision height/altitude (DH/DA), while non-precision approaches are flown to a minimum descent altitude (MDA). These approaches include VOR, NDB, LP (Localizer Performance), and LNAV. A non-precision approach uses a navigation system for course deviation but does not provide glidepath information. Examples include baro-VNAV, localizer type directional aid (LDA) with glidepath, LNAV/VNAV and LPV. An approach with vertical guidance also uses a navigation system for course and glidepath deviation, just not to the same standards as a PA. Examples include precision approach radar (PAR), instrument landing system (ILS), and GBAS landing system (GLS). A precision approach uses a navigation system that provides course and glidepath guidance. There are three categories of instrument approach procedures: precision approach (PA), approach with vertical guidance (APV), and non-precision approach (NPA).

Nonprecision localizer series#

The ICAO defines an instrument approach as, 'a series of predetermined maneuvers by reference to flight instruments with specific protection from obstacles from the initial approach fix, or where applicable, from the beginning of a defined arrival route to a point from which a landing can be completed and thereafter, if landing is not completed, to a position at which holding or en route obstacle clearance criteria apply.' These approaches are approved in the European Union by EASA and the respective country authorities and in the United States by the FAA or the United States Department of Defense for the military. In aviation, an instrument approach or instrument approach procedure ( IAP) is a series of predetermined maneuvers for the orderly transfer of an aircraft operating under instrument flight rules from the beginning of the initial approach to a landing, or to a point from which a landing may be made visually. An ' approach plate' depicting an instrument approach procedure for an ILS approach to Tacoma Narrows Airport in the United States