Simplified directional facility

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Simplified directional facility (SDF) is a localizer-based instrument non-precision approach to an airport, which provides final approach course similar to instrument landing system (ILS) and localizer type directional aid (LDA) approaches, although not as precise.

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The SDF signal is fixed at either 6 or 12 degrees, as necessary to provide maximum flyability and optimum course quality. [1] Unlike an ILS, an SDF does not provide vertical guidance in the form of a glideslope. [1] The SDF course may or may not be aligned with the runway because its antenna may be offset from the runway centerline. Usable off-course indications are limited to 35 degrees either side of the course centerline. [1]

Current SDF approaches in the United States

On January 01, 2018, the SDF approach at KMFI was permanently decommissioned leaving only one remaining operational SDF approach in the United States. [2] [3]

  1. KMOR, SDF RWY 05, Moore–Murrell Airport, Morristown, TN

See also

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Washington County Airport (Pennsylvania) Airport in Pennsylvania, US

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A localizer type directional aid (LDA) or Instrument Guidance System (IGS) is a type of localizer-based instrument approach to an airport. It is used in places where, due to terrain and other factors, the localizer antenna array is not aligned with the runway it serves. In these cases, the localizer antenna array may be offset in such a way that the approach course it projects no longer lies along the extended runway centerline. If the angle of offset is three degrees or less, the facility is classified as an offset localizer. If the offset angle is greater than three degrees, the facility is classified as a localizer-type directional aid (LDA). Straight-in approaches may be published if the offset angle does not exceed 30 degrees. Only circling minimums are published for offset angles greater than 30 degrees. As a "directional aid", and only a Category I approach, rather than a full-fledged instrument landing system (ILS), the LDA is more commonly used to help the pilot safely reach a point near the runway environs, where he or she hopefully can see the runway, at which point he or she will proceed and land visually, as opposed to full Category III ILS systems that allow a pilot to fly, without visual references, very close to the runway surface depending on the exact equipment in the aircraft and on the ground.

Continental Airlines Flight 1883 2006 aviation incident

Continental Airlines Flight 1883 was a Boeing 757 that mistakenly landed on a taxiway at Newark Liberty International Airport on the evening of October 28, 2006. There were no reported injuries or damage, but the narrowly averted disaster was investigated by the National Transportation Safety Board, and caused the Federal Aviation Administration to reevaluate and modify air and ground safety procedures at and around Newark Airport.

References

  1. 1 2 3 AIM 1-1-10 (March 7, 2013 Revision), accessed 2013-07-06
  2. "digital – Terminal Procedures Publication (d-TPP)/Airport Diagrams". FAA . Retrieved 2017-06-23.
  3. "Instrument Flight Procedures Information Gateway". FAA . Retrieved 2017-06-23.