Qantas flight bound for South America turns back to Melbourne almost five hours into journey

A Qantas flight bound for South America has diverted to Melbourne overnight after a mechanical issue forced the plane to turn back over the Pacific Ocean.

Almost 200 passengers on board QF27 from Sydney to Santiago, Chile, were more than four-and-a-half hours into their journey when the Boeing 787 Dreamliner was forced to turn around just past New Zealand.

WATCH VIDEO ABOVE: International Qantas flight turns around mid-journey

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Qantas has confirmed the aircraft experienced a mechanical issue, forcing the emergency diversion.

The plane landed in Melbourne at 11pm on Sunday and couldn’t return to Sydney due to the airport’s curfew restrictions.

Passengers described being well looked after during the ordeal, with one telling reporters the airline provided food and alcohol during the unexpected detour.

Boeing’s 787 Dreamliner aircraft is being examined by engineers for mechanical issues. Credit: James D. Morgan/Getty Images

“It was pretty good. They looked after us. They fed us. They gave us alcohol,” the passenger said.

However, the passenger also expressed frustration at the significant delay.

“Well, it’s disappointing, that’s the big thing, because now we have to go again tomorrow,” they said.

Qantas put all affected passengers up in hotels overnight and has confirmed the flight will re-depart from Melbourne to Santiago at midday on Monday.

Aircraft engineers are currently inspecting the Boeing 787 Dreamliner, however it is unclear what caused the mechanical issue.