Fri, Apr 27, 2012
Aircraft And Equipment Moving Through Critical Areas Can Cause Glideslope Errors
The FAA has published an Information for Operators (InFO) bullitan remindng pilots of the potential for erroneous glideslope, and/or localizer indications caused by movement of aircraft or equipment through ILS critical areas.
The agency has recently received several reports from both pilots and air traffic controllers of instances of localizer, and/or glideslope fluctuations while the aircraft is navigating on the ILS. This well known phenomenon may occur when aircraft or vehicles are moving through the ILS localizer and/or glideslope critical areas, and is due to interference with the ILS signals. In several cases, the aircraft automation/autopilot followed ILS fluctuations causing the aircraft to pitch and roll excessively.
Air Traffic Control (ATC) protects the ILS critical areas when arriving aircraft are inside the outer marker/final approach fix (FAF) on an ILS approach, and the reported ceiling is less than 800 feet or visibility is less than 2 miles. The ILS critical areas are not protected for aircraft outside the FAF. In conjunction with the guidance found in the Aeronautical Information Manual (AIM), pilots should be continually aware of the conditions under which the critical area protections are imposed, and whether or not the ILS fluctuations are likely caused by movement through the ILS Critical Area, or an actual equipment malfunction. In all cases it is imperative that the pilot maintain positive aircraft control whether or not the autopilot is engaged, and coupled to the ILS.
The FAA recommends that directors of safety, directors of operations, directors of training, chief pilots, fractional ownership program managers, training managers, and operators of aircraft should:
Distribute ILS critical area information, reporting recommendations to ATC, and guidance to flightcrews.
Emphasize positive aircraft control with or without the use of automation.
Develop realistic training scenarios to include recognition, awareness, and operating procedures in relation to fluctuations of the localizer, and/or glideslope signal.
More News
"As previously announced on February 29th, our IM-1 mission ended seven days after landing, as Odysseus' mission was not intended to survive the harsh temperatures of the lunar nig>[...]
Marker Beacon An electronic navigation facility transmitting a 75 MHz vertical fan or boneshaped radiation pattern. Marker beacons are identified by their modulation frequency and >[...]
Have A Story That NEEDS To Be Featured On Aero-News? Here’s How To Submit A Story To Our Team Some of the greatest new stories ANN has ever covered have been submitted by our>[...]
Also: Moron With A Laser, EAA Aviation Museum, FAA v Santa Monica Propeller Service, Frontier MEC Lauds FO Boom Supersonic has confirmed details surrounding the successful first te>[...]
We're Everywhere... Thanks To You! Even with the vast resources and incredibly far-reaching scope of the Aero-News Network, every now and then a story that should be reported on sl>[...]