On 23 October 2010, a Partenavia P.68B aircraft, registered VH-IYI (IYI) and an Avions Pierre Robin R-2160 aircraft, registered VH-JXY, were inbound to Jandakot Airport, Western Australia. The pilot of IYI made an inbound call at the visual flight rules (VFR) inbound reporting point of Boatyard prior to the pilot of JXY. However JXY was in front of IYI. Both aircraft then tracked towards the VFR reporting point Adventure World.
Prior to reaching Adventure World the Jandakot Tower Airport controller instructed the pilot of IYI to track as number one and cleared them for runway 24R at Jandakot. The pilot of IYI did not continue to track to Adventure World but headed directly for the downwind leg of the circuit.
The pilot of JXY continued onto Adventure World and was instructed by the controller to track for downwind. The pilot of JXY informed the controller on a number of occasions that they could not see IYI. When both aircraft were on their downwind legs the controller informed the pilot of JXY that IYI was below them.
When IYI turned onto base the pilot observed JXY fly over the top of their aircraft, with about 100 ft separation. The pilot of JXY did not see IYI.
This incident highlights the importance of air traffic control and pilots maintaining situational awareness and an accurate mental picture of the location of other traffic in the alerted see and avoid environment. To assist pilots in maintaining situational awareness air traffic control need to provide timely traffic information to aircraft to ensure they are aware of the proximity of other aircraft.