He was aged 17 when he allegedly carried weapons, including a shotgun, knives and a fake bomb, onto a Jetstar flight bound for Sydney in March 2025.
As the aircraft was in its final stages of boarding at Melbourne's Avalon Airport, with 173 passengers onboard and six crew members, he walked up the plane's front stairs, a children's court was told on Friday.
The teen, who cannot be named for legal reasons, allegedly told crew he had a bomb and demanded access to the cockpit before it's claimed he began to assemble a shotgun.
The teen was restrained by a passenger and the captain before he could get any further.
He allegedly told them he intended to "scare people" and he had planned the conduct for months, a magistrate said.
He is charged with firearm and weapon offences, assaulting crew, attempted hijacking and prejudicing safe operation of an aircraft with intent to kill.
His defence has disputed the alleged offending, including claims he had been planning it since October 2024 and attributed that to his interest in aviation.
Defence lawyers argued the teen's case should remain in the children's court as sentencing there would be adequate because of his mental health conditions, youth and lack of priors.
However, the prosecution argued the penalties available in that court - typically supervision orders - were inadequate to reflect the seriousness of the alleged offending.
Prosecutors claimed exceptional circumstances existed which warranted the matter to be uplifted to the county or supreme court, which a magistrate agreed with on Friday.
This included that his alleged offending took place in a high-risk aviation setting, exposing passengers and crew to "catastrophic harm", and had been politically motivated.
"The alleged offending is of an exceptionally grave character on the material," the magistrate told the court.
"(The teen) engaged in a deliberate and pre-planned attempt to seize control of a commercial passenger aircraft.
"The risks inherent in such conduct are self-evidently extreme."
He is the first child to have terrorism offences uplifted to a higher Victorian court, and the first accused of preparing for and possessing items connected to planned terrorism, the magistrate said.
The magistrate noted some charges carried maximum penalties of 10 years imprisonment in the higher courts.
The teen's lawyers have already flagged he planned to rely on a defence of mental impairment.
A person can be found not guilty by way of mental impairment if it is proven they had a mental illness, disability or brain damage that impaired their judgment during the offending.
No decision has been made on whether the matter will move to the supreme or county court.
The teen, now aged 19, remains in custody and will return to a children's court for a committal mention on June 19.
