At 1221 Western Standard Time on 23 September 2012, as a Piper PA‑28 aircraft, registered VH‑PZK (PZK), approached the threshold for runway 09 at Rottnest Island, Western Australia, the pilot observed an aircraft about 650 m ahead on the reciprocal heading at the same level. As the pilot of PZK initiated a sharp right turn he observed the other aircraft also turn right. The other aircraft was later identified as a Cessna 441 aircraft, registered VH‑VEJ (VEJ). The lateral distance between the aircraft reduced to 0.2 NM.
The pilots of both aircraft made all the necessary broadcasts on the common traffic advisory frequency (CTAF) although subsequent to the event, the pilot of PZK realised the aircraft’s radios were not working. VEJ was conducting a flight safety check flight of the Rottnest Island aerodrome and instrument approaches.
The flight safety checks being conducted by VEJ were on behalf of the Civil Aviation Safety Authority (CASA). The crew of VEJ was responsible for coordinating the flight check with aerodrome operators and CASA was responsible for communicating with aircraft operators. CASA had issued a press release on their website and the information was tweeted on twitter; however, no Notice to Airmen (NOTAM) was issued nor were any newspaper advertisements made.
As a result of this occurrence, the aircraft operator of VEJ advised the ATSB that they will not conduct flight safety check flights during busy periods at non-towered aerodromes. Additionally, CASA, in conjunction with the aircraft operator of VEJ, will ensure a NOTAM is issued for future flights to promulgate information applicable to this type of operation.
When operating outside controlled airspace, it is the pilot’s responsibility to maintain separation with other aircraft. For this, it is important that pilots utilise both alerted and unalerted see-and-avoid principles. Pilots should not assume that an absence of traffic broadcasts means an absence of traffic. CASA have published a number of Civil Aviation Advisory Publications (CAAPs) dealing with operations at non-towered aerodromes and the importance of not relying solely on radio broadcasts for traffic advice. In addition, the ATSB has published A pilot’s guide to staying safe in the vicinity of non-towered aerodromes (AR-2008-004(1)).