Jetstar says one of its pilots spread so many lies about the company that it had no choice but to fire him.
The budget airline is being taken to Fair Work Australia over the decision, but says its case for dismissal is strong despite a "political strategy" being waged by one of the main airline unions.
Jetstar pilot Joe Eakins, who had been with the company for three years, lost his job last week after expressing concerns about a range of cost-cutting measures at the airline, including the increasing use of foreign-based cabin staff.
Mr Eakins, 31, from Sydney, said he was "shocked and appalled" that his career with the carrier, which is owned by Qantas, had been ended for speaking out.
"I believe the concerns I voiced were reasonable and legitimate," Mr Eakins told reporters in Sydney on Friday.
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"I was acting within my rights as a union representative who advanced views of the association."
While a first officer with Jetstar, Mr Eakins wrote an opinion piece in Fairfax media saying the airline's safety culture could be "obliterated if the offshoring push continues".
In the column, Mr Eakins criticised "draconian workplace conditions" that could be imposed through the use of foreign "bases of conveniences".
The Australian and International Pilots Association (AIPA) said the pilot should be praised for his bravery in standing up as a whistleblower.
"We are going to take this as far as we can," the organisation's president, Barry Jackson, said.
But the airline labelled the pilot's claims in the media as "malicious" and full of "misinformation" that damaged the company's reputation.
David Hall, CEO of Jetstar Australia and New Zealand, said claims on wages and conditions were "absolutely untrue".
While some jobs have been moved offshore, pilots maintained wages and conditions identical to anyone working inside the country, he said.
"We need flexibility as we move through the various regions - we need to be competitive in the regions in which we operate," Mr Hall told reporters at Jetstar's Melbourne office on Friday.
"(But) at no times do we compromise existing terms and conditions."
He said the pilot was fired for breaching the company's code of conduct and employment arrangements, not for raising and reporting legitimate concerns - which is encouraged by the airline.
"This does not relate to safety," Mr Hall stressed.
"Misrepresentations were put into the market around a whole array of information totally unrelated to safety in the majority of cases."
The airline's chief pilot, Mark Rindfleish, said pilots should be encouraged to raise concerns, but only through the appropriate channels.
"What we don't encourage is the sort of behaviour that Joe Eakins has done," he said.
The AIPA has consulted lawyers and is vowing to take action at the workplace relations tribunal to claim unfair dismissal, but Mr Hall said that was a "political strategy" not in the best interests of the individuals involved.
