The Australian model faced the prospect of spending 21 years in America's harsh federal prison system for turning a Melbourne to Los Angeles flight into drunken, violent chaos for 205 other passengers - what the judge called a "nightmare flight".

"I am filled with nothing but shame and humiliation," the 24-year-old from Melbourne, a former Miss World Australia finalist who has worked with elite designers including Alexander Wang, told the court on Monday.

Judge Carney showed mercy, choosing not to put her behind bars and instead sentencing her to 100 hours of community service and three years probation.

She will have to undergo drug tests, substance abuse counselling and abstain from alcohol. Mornyang said she has been sober for six months.

The court heard Mornyang ordered "several glasses of wine" on the January 21 United Airlines flight but was was cut off when her behaviour deteriorated.

She slapped a flight attendant, struck other passengers as she walked down the plane's aisles, yelled vile racial taunts at a black air marshal who tried to restrain her and called another flight attendant "dumb white trash".

Prosecutor Miri Song said when Mornyang was told on the plane she had hit passengers she replied: "I don't care."

Audio of her behaviour was played at her March trial in Los Angeles.

The jury found her guilty of a felony charge of interference with a flight crew member and a misdemeanour count of assault.

"It was a nightmare flight," Judge Carney told the court. "I can't imagine what it was like for the other passengers."

Prosecutors had asked for a one-month prison sentence but the judge pointed to Mornyang's "quite sad and quite tragic" life.

Mornyang arrived in Australia as a 10-year-old refugee from Sudan. Two men raped her in an Adelaide car park when she was 17 - an assault she made public in 2017.

The court heard she had struggled with depression and drank alcohol to suppress her "childhood traumas".

"It was a girl crying out for help," Mornyang said.

Judge Carney said he had sentenced terrorists, murderers, drug traffickers and fraudsters to prison, adding: "They need to be put in custody."

He said Mornyang did not deserve prison time.

"I want you to have a very happy and wonderful life," the judge said.

"Hopefully I will never see you again - don't take that the wrong way."

Australian Associated Press