On 21 February 2012, at about 0900 Eastern Daylight-saving Time, at about 8 NM east of Gunnedah, New South Wales, a Piper aircraft company PA-39 aircraft registered VH-ICS (ICS) and a Pacific Aerospace CT/4B aircraft registered VH-YCR (YCR) were conducting instrument flight rules (IFR) flying training operations, in visual metrological conditions on a reciprocal track between Tamworth and Gunnedah. There was a flying instructor and two students on board ICS and a flying instructor and one student on board YCR.
YCR received traffic advice from Brisbane Air Traffic Services (ATS) on two other aircraft in the area below 5,000 ft, including ICS. YCR was nearing Gunnedah at 6,000 ft above mean sea level, and broadcast their intention to over-fly Gunnedah at 6,000 ft, on the Gunnedah common traffic advisory frequency. ICS then requested traffic information for a departure from Gunnedah to Tamworth, at 7,000 ft and later advised Brisbane ATS that they were 5 NM outbound from Gunnedah and passing 6,000 ft. Both aircraft were on the same bearing and unable to contact each other; both took evasive action at 6,000 ft. The PIC of YCR estimated that at the time of the event their separation was 1 NM laterally. Neither crew sighted the other aircraft.
This incident highlights the importance of applying the principles of 'see and avoid' in conjunction with an active listening watch and clear communications when operating in the vicinity of a CTAF.