A Sri Lankan man who threatened to detonate a bomb on a Malaysia Airlines plane has been jailed in Australia.

Manodh Marks, 26, forced Kuala Lumpur-bound jet MH128 to turn back to Melbourne in May last year after he tried to access the cockpit.

He was later found not to be carrying explosives and in a drug-induced psychosis, a court heard.

It is the first time Australia has jailed a person for attempting to take control of an aircraft.

Marks will be deported after serving a maximum sentence of 12 years, judge Michael McInerney told the County Court of Victoria on Thursday.

"The passengers and crew certainly were not only concerned, but convinced, that you were indeed in possession of a bomb," the judge said in his sentencing remarks.

The flight, carrying more than 200 people, landed safely about 15 minutes after Marks was tackled to the ground by passengers.

Flashing items
Marks, who was in Australia on a student visa, had been released from a psychiatric facility on the day of the incident.

The court heard that he had taken crystal methamphetamine, known locally as ice, on the way to the airport.

Shortly after take-off, he brandished two black items - later found to be a portable speaker and a battery pack - with flashing lights.

"I have a bomb with me," Marks told the crew, according to Fairfax Media.

"I want to talk to the captain. I want to talk to the pilot. Don't come near me. I want to destroy this aircraft. I will destroy this plane."

About five minutes later, Marks was subdued by passengers who bound his hands with cable ties.

The Airbus A330 landed safely a short time later. Mr McInerney said the threat had placed intense stress on the pilots, putting passengers at risk.

Response controversy
At the time, Australian police were criticised for taking almost 90 minutes to board the plane after it landed.

Victoria Police Chief Commissioner Graham Ashton said police had initially treated it as a possible terrorism incident, before deciding it was "a case involving a mental health issue".

"I certainly appreciate when you are on a plane in that situation one minute could seem like an hour," he said.

"The objective in any serious incident like this is to get every member of the crew, every passenger off the plane safely, and that is what was able to be achieved."

Marks will be eligible for parole after nine years.