The actions of air traffic controllers have been put under scrutiny after the fatal crash of a Mooney west of Coffs Harbour in 2019.
Mooney VH-DJU was on a flight from Murwillimbah to Taree in September 2019 when it was refused a clearance to transit controlled airspace at 6500 feet, leading to the aircraft descending into non-VMC and colliding with high terrain. Two people on board the aircraft were killed.
The ATSB investigation report released today concluded that the information provided by ATC impacted the pilot's decision to descend, and that the pilot was not properly prepared for the conditions encountered.
“Information provided by air traffic control likely resulted in the pilot deciding to descend the aircraft from 6500 feet instead of other available safe options, such as proceeding around the Class C airspace at or above 6500 feet, diverting, or descending to the north of Grafton to proceed coastal beneath the cloud layers south to Taree,” said ATSB Chief Commissioner Greg Hood.
“The ATSB also found that the pilot was not carrying suitable navigation equipment–the pilot was likely using a handheld GPS unit while air navigation charts for the area were found stowed in a flight bag–and had most likely not obtained the required weather forecasts.
"These factors reduced the pilot's ability to manage the flight path changes and identify the high terrain. This led to the aircraft being descended toward the high terrain in visibility conditions below that required for visual flight, resulting in controlled flight into terrain.”
After being refused a clearance to transit at 6500 by a trainee controller, the pilot was given the option of contacting the Class D controller at Coffs Harbour, who subsequently advised the pilot that VFR flight would be possible only below 1000 feet due to cloud.
After announcing his intention to descend to "not above 1000 feet", the pilot diverted slightly west and descended to 4500 feet, infringing the C class airspace anyway. He then reported clear at 4100 feet and continued to Taree, before descending in the vicinity of the high terrain near Dorrigo.
The investigation also found that the pilot was not provided clearance to transit Class C airspace due to the trainee controller’s conservative assessment of their workload, although there was no conflicting traffic, meteorological factors or limiting air traffic control instructions or procedures that would have precluded providing the clearance.
The trainee’s supervisor accepted the assessment as an alternate option – transiting through Coffs Harbour Class D airspace – was provided to the pilot.
“The pilot was not provided with a clearance to transit Class C airspace despite there being no limiting meteorological factors,” Hood said. “Instead, the Class C controller provided the option to seek a clearance at a lower altitude with an increased risk of encountering poor weather.
“Further, the limited information provided by the Class D controller to enter that airspace probably led to the pilot’s decision to descend into a hazardous area instead of opting for other available safe options.”
During the investigation, the ATSB found that the pilot had also not completed the required flight reviews or proficiency checks.
"This resulted in the pilot not possessing the required licence to undertake the flight and likely led to a deterioration in the knowledge and skills required for effective flight management and decision‑making," the report states.
“This accident illustrates the significant influence that air traffic control can have on the conduct of a flight,” Hood added.
“And it also serves as another reminder of the risks for visual flight rules pilots flying into non-visual conditions.
“As a former air traffic controller and private pilot myself, I urge all current controllers and private VFR pilots to read this thorough and illuminating report. It contains pertinent lessons that others can learn from.”
The full report is on the ATSB website.