| Occurrence Briefs are concise reports that detail the facts surrounding a transport safety occurrence, as received in the initial notification and any follow-up enquiries. They provide an opportunity to share safety messages in the absence of an investigation. |
What happened
On 21 September 2020, two Cessna 208Bs departed Proserpine, Queensland, for scenic charter flights. The lead Cessna had one pilot and 12 passengers on board and the trailing Cessna had a pilot and 13 passengers on board.
After departing Proserpine, both aircraft climbed to 1,000 ft and began to track towards Hamilton Island. The pilots reported that they would normally transit the area between 1,500 ft and 2,000 ft, but elected to maintain 1,000 ft as the cloud base was at 1,500 ft. When 10 NM west-south-west of Hamilton Island Airport, the pilot of the lead Cessna broadcast on the Hamilton Island common traffic advisory frequency (CTAF) to advise their intentions to track via the northern tip of Dent Island and Hamilton Island at 1,000 ft for Whitehaven Beach (Figure 1). No replies were heard from any other aircraft in the area.
At approximately 0800 Eastern Standard Time, the lead Cessna was approaching the northern tip of Dent Island and a Eurocopter EC130 departed Hamilton Island Airport climbing to 1,000 ft for a ferry flight to Shute Harbour. The EC130 then turned left to track towards Shute Harbour. The pilot of the helicopter reported making entering runway, take-off and departure radio calls on the Hamilton Island CTAF but did not hear any replies. The helicopter pilot then sighted the lead Cessna on a crossing track at the same height. The pilot of the lead Cessna also sighted the helicopter.
Both pilots manoeuvred to avoid a collision. The two aircraft came into close proximity, with the lead Cessna passing under the EC130, resulting in an estimated separation of 50 ft vertically and 100 m horizontally.
Figure 1: Extract of Google Earth showing relevant positions
Source: Google Earth – annotated by ATSB
Safety message
Research for the ATSB report Safety in the vicinity of non-towered aerodromes (AR-2008-044) found that insufficient communication between pilots and breakdown of situational awareness were the most common causes of safety incidents near non-controlled aerodromes. The report advises pilots to avoid transiting circuit areas where possible and highlights the importance of transiting circuit areas at least 500 ft above circuit height to maintain vertical separation with departing aircraft.
Further information can be found at:
- A pilot's guide to staying safe in the vicinity of non-controlled aerodromes
- See and Avoid
- Limitations of the See-and-Avoid Principle
- Operations at non-controlled aerodromes
About this report
Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.