A second incident from the material obtained by Melbourne researcher Paul Dean (click here) from Air Services Australia, happened in April 2009. A Sydney research associate of mine, who wishes to remain anonymous, and myself, provide the following "English" translation for blog readers.
1. At 1.53 zulu time on Friday 10 April 2009, (9.53am WAT; or 11.23 CST), an Embraer 170 aircraft belonging to the Airnorth company (a regional airline based in Darwin, Northern Territory) was flying between Darwin, Northern Territory, and Kununurra, Western Australia, a distance of 237 nautical miles.
2. Flight number 332 was on descent to Kununurra at a height of about 9,000 feet when the crew reported an encounter with an "unknown aircraft" close enough to their plane to be described as an "airprox." An "airprox" is a situation in which the safety of the aircraft is deemed to have been compromised. The "unknown" was travelling in the opposite direction to flight 332.
3. Subsequent questioning of the crew found that the "unknown" was located about 3-4 nautical miles east of flight 332. The "unknown" activated flight 332's traffic collision avoidance system (TCAS) and TCAS provided a "resolution advisory", which is a suggestion for the pilot to either climb or descend to avoid a potential collision.
4. Flight 332 crew did not visually see the "unknown." Weather conditions at the time meant the crew of flight 332 were flying under visual meteorological conditions.
5. Flight 332 used its very high frequency radio to try and contact the "unknown." However, there was no response.
6. Air traffic surveillance is not available of this part of the Australian airspace, so the "unknown" was not able to be confirmed by air traffic controllers.
7. No flights matching the "unknown" were known to the air traffic surveillance system.
8. I checked the database of the Australian Transport Safety Bureau for a possible ATSB report on this incident, but failed to find any trace of such a report.