While flying a coupled instrument landing system (ILS) approach to runway 35 at Canberra, the crew received a ground proximity warning system (GPWS) "terrain" warning at 470 ft above ground level. As the aircraft was in visual conditions at the time, the crew elected to continue the approach.
The crew reported that, at the time of the warning, the aircraft was established on the ILS glideslope and descending at 650 ft/min. However, the T-VASIS indicated one dot low. Immediately prior to the warning, the radio altimeter indication rapidly increased, and then decreased, apparently triggering the warning.
This occurrence was one of 12 similar occurrences which involved GPWS warnings to crews of BAe146-300 aircraft at the same position on the runway 35 ILS final approach at Canberra. As a result, the Bureau of Air Safety Investigation is currently investigating a perceived safety deficiency related to these warnings. Any safety output issued as a result of this analysis will be published in the Bureau's Quarterly Safety Deficiency Report.
|Date:||19 June 1998||Investigation status:||Completed|
|Time:||0815 hours EST|
|State:||Australian Capital Territory||Occurrence type:||E/GPWS warning|
|Release date:||01 January 1999||Occurrence category:||Incident|
|Report status:||Final||Highest injury level:||None|
|Aircraft manufacturer||British Aerospace PLC|
|Aircraft model||BAe 146|
|Type of operation||Air Transport High Capacity|
|Damage to aircraft||Nil|
|Departure point||Brisbane, QLD|