A leaked report on Regional Express's (Rex) maintenance operations and corporate culture has prompted the Civil Aviation Safety Authority (CASA) to investigate the airline.
CASA has said it will be investigating claims of maintenance and safety issues at Rex and would be asking more questions of the airline this week.
The questions by CASA follow the submission of a report by the Australian Licenced Aircraft Engineers' Association (ALAEA) to CASA alleging issues around safety and maintenance operations at the airline.
The report was leaked but ALAEA says it was not responsible. It is understood that copies of the report went to CASA, ASTB (Australian Transport Safety Bureau) and one other (unnamed) organisation.
A spokesman for ALAEA confirmed a report was made to CASA about Rex "as a result of several years of ongoing issues". It is understood the report claims the issues are as a result of the culture of the organisation.
But Rex's chief operating officer Neville Howell claims the accusations have been raised by "a disgruntled engineer and his union, first to the Fair Work Commission and then to CASA".
"We believe that our safety culture, as part of the Safety Management System, is second to none," Mr Howell said.
He called the accusations "baseless" and said that Rex had "invited senior management of CASA on June 18 to have a full briefing on the matter as well as to discuss the professional failings of the disgruntled engineer".
However CASA has responded stating that further investigations were taking place.
"CASA is carefully examining the allegations and now has responses from Rex. We will be asking further questions of Rex this week to make sure maintenance work at the airline is meeting all required standards. If any safety issues are found CASA will take appropriate and timely action," the spokesman for CASA said.
"At this point CASA has not taken any steps which impact on REX operations," he added.
Mr Howell said that CASA had written to the airline on May 22 stating that "the board and management of CASA have no current safety concerns with Rex".
"Rex is proud of its Safety Management System and CASA has written to us on 22 May 2019 to advise: 'I would like to re-iterate my previous advice that the Board and Management of CASA have no current safety concerns with Rex. ...CASA is satisfied that Rex is currently meeting all its obligations.'"
"Rex will leave it to the safety authority to judge if our safety culture is lacking in any manner," Mr Howell said.