On 19 July 2012, at about 1629 Eastern Standard Time, the pilot of a Cessna 172S aircraft, registered VH-EOP (EOP), received an air traffic control (ATC) clearance to land on runway 35 Right at Moorabbin Airport, Victoria.

Several seconds later, the pilot reported observing another Cessna 172S aircraft, registered VH‑EWE (EWE), pass overhead from his right, about 10-20 metres in front. In response, he reduced engine power and raised the nose of the aircraft slightly to slow the aircraft and increase separation. The pilot then advised ATC, who immediately instructed the pilot of EWE to conduct a go-around.

The flight instructor in EWE reported that he was not aware of EOP operating in the circuit until after the incident occurred.

While research has shown that when searching for traffic, alerted see-and-avoid is eight times more effective than unalerted see-and-avoid, pilots should be mindful that the absence of a traffic broadcast does not necessarily mean the absence of traffic. Pilots should remain vigilant and employ both unalerted and alerted see-and-avoid principles to ensure the greatest level of traffic awareness is achieved.

Aviation Short Investigation Bulletin - Issue 13