The regional airline Rex has denied claims that one of its planes was filmed with unrepaired corrosion around the propeller.

On Friday, Sydney’s Daily Telegraph published footage that allegedly showed corrosion on a plane that flew on Thursday from Kangaroo Island to Adelaide.

The footage was filmed by an engineer, the newspaper said.

But the airline, which on Tuesday denied accusations that staff were put under pressure to ignore faults, said the latest footage had been misdescribed and posed no threat to safety.

The deputy chairman of Rex, John Sharp, told ABC radio the brown stain was not corrosion, and could be “wiped off”.

“It’s just what I would call some muck that builds up on a piece of metal in an engine,” he told ABC radio on Friday. “What you see in there, it’s claimed as corrosion, was actually wiped off yesterday. It was wiped off. It was wiped off using a solvent.”

The mayor of Kangaroo Island, Michael Pengilly, told the ABC he was not concerned about Rex’s safety standards.

On Sunday, the Telegraph released details of a report, submitted by the Australian Licensed Aircraft Engineers’ Association (Alaea) to the Civil Aviation Safety Authority (Casa), that accused Rex of bullying and intimidating staff into not reporting faults.

But the airline said the claims were “baseless” and had been made by a “disgruntled” engineer.

Rex also accused Casa of leaking the report, calling the regulator “despicable and cowardly”.

On Thursday, Rex released a statement saying it had high safety standards and satisfied engineers.

It said Casa had sent inspectors to Rex’s base to “survey five random engineers” and see “if they share the feelings of the disgruntled engineer”.

“If the workplace environment is as bad as the disgruntled engineer portrayed, the turnover of engineers at his base would be correspondingly very high,” Rex said.

“In fact, we have an average of only one resignation a year over the last two years (out of 18 licensed engineers), at a time when licensed aircraft engineers are at critical shortage Australia-wide. This speaks volumes.

“If the claims were true, then one would expect to find a decline in the defect reporting rate over time. The reality is the complete opposite and over the last two years the reporting rate per 1,000 hours has actually increased by over 10%.”

A spokesman for Casa said it was investigating the Alaea report and would also investigate the video.

In March 2017, a Rex flight had to make an emergency landing after a propeller fell off at 6,000 feet.