A de Havilland Canada DHC-8, VH-TQT, was inbound to Mildura from Melbourne and overflew a glider that was crossing from left to right. At the time, TQT was descending through 7,300 ft and the crew had made inbound and top of descent broadcasts. The aircraft, which were outside controlled airspace, passed within an estimated 30 to 60 m. VH-TQT was on the area frequency 122.1 MHz and the glider, VH-GDJ, was on the glider frequency 122.7 MHz.
AIP Australia ENR 5.5, paragraph 1.1.3, states: "Except for operations in controlled airspace, gliding operations may be conducted no-radio, or may be on frequencies 122.5MHZ, 122.7MHZ or 122.9MHZ, which have been allocated for use by gliders. Unless otherwise authorised, gliding operations in controlled airspace must be conducted using the appropriate air traffic control frequency. Radio equipped gliders at non-controlled aero-dromes will use the MBZ frequency or CTAF. Whenever possible, when operating above 5,000 ft AMSL outside a MBZ or CTAF area, glider pilots are expected to listen out on the area VHF and announce if in potential conflict."
Consequently, in the circumstances of this occurrence, the glider pilot was "expected to listen out on the area VHF" but was not required to do so.
The pilots of both aircraft advised that, from the time of sighting of the other aircraft, they had no time to take avoiding action.
The Chief Flying Instructor of the Sunraysia Gliding Club has liaised with the Manager Flight Safety of Southern Australia Airlines on the development of procedures to prevent a recurrence of this incident.
As a result of this and other occurrences the Bureau of Air Safety Investigation is currently investigating a safety deficiency. The deficiency relates to the appropriateness of gliders and other sports aviation aircraft not being on an area frequency when flying above 5,000 ft. Any safety output issued as a result of this analysis will be published in the Bureau's Quarterly Safety Deficiency Report.
|Date:||04 February 1999||Investigation status:||Completed|
|Time:||1603 hours ESuT|
|Location:||28 km SE Mildura, Aero.|
|State:||Victoria||Occurrence type:||Near collision|
|Release date:||24 September 1999||Occurrence category:||Incident|
|Report status:||Final||Highest injury level:||None|
Aircraft 1 details
|Aircraft manufacturer||de Havilland Canada|
|Type of operation||Air Transport Low Capacity|
|Damage to aircraft||Nil|
|Departure point||Melbourne, VIC|
Aircraft 2 details
|Aircraft manufacturer||Grob - Burkhart Flugzeugbau|
|Type of operation||Gliding|
|Damage to aircraft||Nil|
|Departure point||Yamba, VIC|