Teenager felt 'weight off his shoulders' after Avalon Airport plane incident, court hears

A teenager who allegedly tried to hijack a plane last year at Avalon Airport felt relieved when passengers restrained him, telling them it was a "weight off his shoulders", his lawyers have said.

The teenager, who cannot be identified for legal reasons, was allegedly carrying a shotgun when he was overpowered on the Jetstar flight in March last year.

Prosecutors allege he entered the airport through a hole in a security fence and boarded the plane under the guise of being a maintenance worker.

On Wednesday, a Victorian Children's Court heard the teenager later told police he wanted to "subdue the crew", but did not want to alarm others on the plane.

His lawyer, Patrick Doyle SC, said the teenager was mentally impaired at the time of the incident.

"[He] was clearly not thinking clearly at the time this offence was committed. He was a young man under tremendous mental strain," Mr Doyle said.

The teenager later described feeling "a weight off his shoulders" and thanked the people who restrained him, the court heard.

"You're a good man, you know what you're doing," he allegedly told Barry Clark, a passenger who intervened.

Prosecutors allege the teenager brought an "explosive device" on the plane, but Mr Doyle said it was an "obvious fake".

"It's remarkable how he got through the fence undetected and that a hi-vis vest and a tool belt was a sufficient disguise to enable him to walk casually onto the aeroplane," Mr Doyle said.

"But once he got there … the reality is that this was ever [only] going to end one way."

The court heard the teenager had a series of mental health conditions, and according to a neuropsychologist's report, he suffered "significant deterioration" around the time of the incident.

He skipped work, was heard crying loudly in his bedroom and told friends he was depressed after learning that a girl he was interested in kissed someone else at a party.

Friends were later disturbed when the teenager told them he found a "great path" and had "new friends".

The teenager's "political motive" — or whether a coherent one existed — remains a key dispute between prosecutors and the defence.

A suppression order over the case prevents media reports detailing any foreign groups the teenager may have been in contact with.

Mr Doyle said before the Avalon incident, the teenager searched online for information about shooting down Russian and Turkish military aircraft and made searches about a Syrian airport and an air base.

He said the teen had "an interest in aviation and airports", and rejected the prosecution's claims that he had been planning to hijack a plane for five months.

Prosecutor Paul Holdenson KC said the teenager was "clearly committed" to a political or ideological motivation.

"It was planned, he succeeded to the point of getting into the plane and making threats and had the means available to him to put those plans into effect and therefore achieve his goal," he said.

The teenager has been in custody since March 2025.

Prosecutors and defence lawyers are fighting over whether the case should shift from the Children's Court to a superior jurisdiction, such as the County Court or Supreme Court.

A Children's Court judge will rule on the application next month.