Showing posts with label critcal area. Show all posts
Showing posts with label critcal area. Show all posts

Wednesday, July 25, 2012

ILS Signal Interference

G R Mohan | 6:20 PM | | | | Best Blogger Tips
 
Recently a commercial large jet was cleared for an ILS approach to Runway 28 at Chicago O’Hare airport. While inbound to intercept the Glide slope, the cockpit indications were initially full up. Abruptly the display changed from full up to full down position and the aircraft pitched down and descended to stay on the glide slope. The pilot reacted to disconnect the autopilot, but not before the aircraft had descended a 100 ft. The display restored to full up deflection soon thereafter.
 This anomaly was most likely caused by disruption of the Glide slope signals caused by a large cargo aircraft holding for take-off. ATC controller had advised the crew of this aircraft that they were not required to protect the ILS critical area.