A charity that flies sick children from regional areas to the city for crucial medical treatment has hit back at claims it has a fatal accident rate seven times higher than other private flights.
The report comes from the Australian Transport Safety Bureau, which is investigating the safety of Angel Flight compared to other private flying operations, after a second fatal accident in the past decade.
The ATSB investigation came after a pilot and two passengers were killed when an Angel Flight service crashed at Mt Gambier in South Australia in June 2017.
Businessman Grant Gilbert, 78, was flying the SOCATA TB-10 Tobago to take 16-year-old Emily Redding to Adelaide for medical treatment, accompanied by her mother Tracy.
The investigation found Mr Gilbert, who had less than three years' experience, took off in heavy fog despite not being qualified to fly in cloud using the plane's instruments.
Shortly after, he likely lost visual cues and became spatially disorientated. The plane crashed within 70 seconds.
The same day, two Rex airline flights into Mt Gambier were delayed by poor weather.
Another plane running an Angel Flight mission crashed in similar circumstances near Nhill in Victoria in 2011, also killing all three people on board.
Angel Flight has more than 3000 volunteer pilots on its books and organises about 1600 flights a year.
A spokesperson for the charity said it engaged two senior expert statisticians and an analyst, all of whom concluded that the rate was not significantly different than other private airlines.
"The ATSB also chose to compare only the passenger-carrying sectors of flights coordinated by the charity," they said.
"It disregarded the flights ... where the aircraft flew from home base to the city collection points, the return trips back to base, and the positioning flights to collect passengers from their own home towns.
"It did, however, include those flights when reporting 'occurrences' against the charity flights."
The statement added that the ATSB had not adopted its own protocols of counting flight hours for general aviation accidents - instead, it counted only flight numbers.
Angel Flight expressed frustration it was not acknowledged that all volunteers are CASA-licensed, CASA-trained, and CASA-tested at least every two years.
The charity also shut down the recommendation that it should book people on airlines for travel, claiming it did not factor in cost, flight schedules in regional areas and the strain on families.
It added, it uses airline flights where practicable and necessary, and will continue to utilise these services.
The ATSB report stated Angel Flight pilots were more likely to make operational errors when compared to other private operations.
"This investigation has shown that those conducted for Angel Flight are actually less safe than other private operations, let alone charter and scheduled airline flying," Commissioner Hood said.
The ATSB reported stated that it considered flight hours as a normaliser, however, were assessed as more limited in answering the safety objectives.
John Smith, captain of flying at Wagga City Aero Club, questioned the report, labelling the data as "rubbish".
Mr Smith has been a pilot for 45 years, volunteering on and off with Angel Flight.
"It's very damming and very irresponsible of a department with that much power," he said.
"It would be a real shame if Angel Flight has to close down because of this discrimination.
"It's discriminatory against country people because city people have all the medical services at their fingertips."
Mr Smith added that commercial operations would benefit from the charity operator being shut down.