Hollywood star John Travolta, who became an ambassador for Qantas Airways in June 2002, may have his son waiting in the wings if he decides to step down from the position one day.

On Saturday (Nov 9), he posted a rare photo of his son Benjamin on Instagram. The eight-year-old is seen with a friend in a plane's cockpit, with both wearing pilot caps.

The 65-year-old actor, famous for movies such as Saturday Night Fever (1977), Grease (1978) and Pulp Fiction (1994), wrote jokingly: "My son Ben is taking my place! His first A380 @qantas flight."

Travolta, who played an air force pilot in the John Woo-directed movie Broken Arrow (1996), is an aviation fan and certified private pilot who owns several aircraft. He donated a vintage Boeing 707 plane to an Australian aviation museum two years ago.

He and his wife, actress Kelly Preston, have two other children - elder son Jett, who died from a seizure at 16 in 2009, and daughter Ella Bleu, 19.