A Cessna 206 triggered an air traffic control terrain alert after conducting a visual flight rules take-off from Archerfield close to last light, an ATSB short investigation report details.
On 24 July 2025, the Cessna 206G was preparing for a training flight under instrument flight rules from Archerfield to Rockhampton. On board was an instructor and a pilot under training for a private instrument rating.
An instrument flight rules (IFR) flight plan was submitted with a departure time of 1730, prior to last light at 1739. CTAF procedures were in place after the Archerfield tower had closed at 1700.
However, the take-off occurred seven minutes later than planned, just two minutes prior to last light, and the instructor elected to conduct a visual flight rules departure, instead of an IFR departure.
This meant when last light occurred shortly after take-off, the aircraft was below the 2,900 ft minimum altitude when it left the circling area, triggering a minimum safe altitude warning at Brisbane Centre ATC.
ATC requested the pilots expedite their climb to at least 3,000 ft, which they did. The flight then continued without further incident.
“Despite the IFR plan, the instructor elected to conduct the VFR Northern departure instead of conducting an IFR departure,” ATSB Director of Transport Safety Stuart Macleod said.
“While it was feasible that the aircraft would reach the required minimum altitude before last light based on their flight plan departure time of 1730, take-off actually occurred 7 minutes later than what was flight planned.”
Mr Macleod said the incident highlights the importance of planning, particularly around times of day when rules change, such as the transition from day to night.
The final report notes the instructor opted for a VFR departure for the IFR flight because they believed it was the preferred method for Brisbane ATC traffic management.
In line with this, during the investigation the ATSB became aware of a potential conflict point over Archerfield Airport, for IFR departures from Archerfield and IFR arrivals into Brisbane Airport runway 01R.
“IFR arrivals to Brisbane runway 01R pass overhead Archerfield at 3,000 ft, which is the same altitude ATC needs IFR departures from Archerfield to climb to in the circling area before departing, creating a potential traffic conflict point for ATC to manage,” Mr Macleod explained.
“This concern is understood by the parties involved, and a project is underway to develop a procedural instrument departure from Archerfield Airport.”
Read the final report: Flight below minimum altitude involving Cessna 206G, VH-ARS, 6 km north-west of Archerfield Airport, Queensland, on 24 July 2025