Hollywood star Tom Cruise revealed on Tuesday that a nauseous film crew was "vomiting in between takes" while shooting a mid-air zero-gravity crash stunt during the production of his latest blockbuster "The Mummy".

Cruise, who is known for performing his own stunts, told hundreds of fans in Sydney that the death-defying scene was originally envisioned for his "Mission Impossible" series.

But he decided the high-altitude shoot would be better suited to his new monster flick, which tells the story of an ancient princess who is awakened from her crypt beneath the desert and unleashes a malevolence that has grown over millennia.

"When we were doing it, the crew, they were vomiting in between takes," he said.

"We went up into an aircraft and we were zero G for 34 seconds and we did it 64 times.

"That is why it looks the way it does -- it is real."

The superstar was in Australia to promote the new film, alongside co-stars Russell Crowe, Annabelle Wallis and Sofia Boutella, under the direction of Alex Kurtzman.

The film is an "entry point" into Universal Pictures' new franchise known as Dark Universe, based on a genre of classic monster films, with Johnny Depp and Javier Bardem slated for future releases.

"You're going to see 'Creature from the Black Lagoon', 'Bride of Frankenstein', 'Wolf Man', 'Dracula' -- all the monsters we grew up loving," Kurtzman told the Sydney crowd. "We are going to build a universe."