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Simplified Directional Facility (SDF) (GA105)
DGIF baseline 2026-1, the latest. Earlier baselines: timemap.
RDF: ga105.ttl
- Name
SimplifiedDirectionFacility- Kind
- FeatureType
- Definition
- A directional aid facility providing only lateral guidance (front or back course) for a terminal instrument approach from a final approach fix.
- Description
- The Simplified Directional Facility (SDF) provides a final approach course similar to that of the Instrument Landing System (ILS) localizer, however an SDF is intended only for use by non-precision approach procedures. It is generally less accurate than a localizer, and may not be aligned to the runway. The SDF signal is fixed at either 6 or 12 arc degrees course width as necessary to provide maximum flyability and optimum course quality.
- Synonyms
- SDF
- Accepted
- 2013-10-18
- Geometry
- point, multipoint, curve, multicurve, surface, multisurface, solid, multisolid
- Subtype of
- GA033 Aeronautical Radio Navigation Installation
- Attributes
- CLW Localizer Course Width — multiplicity 0..1; datatype AngleMeasureMeta
- BEA Magnetic Bearing — multiplicity 0..1; datatype AngleMeasureMeta
- TBE True Bearing — multiplicity 0..1; datatype AngleMeasureMeta
- Associations
- RWOI terms naming it
- RWO_03412 Simplified Directional Facility (SDF)
Source: DGIF 2026-1 QEA model, DGIWG. Standard: DGIWG 206-3. Licence: CC BY 4.0, © DGIWG.