Plane lands safely in Sydney with hole in engine casing

China Eastern flight from Sydney to Shanghai has been forced to turn around after an engine failure

Passengers on board flight MU736 were forced to spend the night in Sydney before resuming their journey.

Aircraft tracking showed the plane circling the area for one hour, while the pilots waited for a safe time to land. The phrase "engine number one f*****" can be heard twice in the audio, reported.

"I was really scared". I was really scared. "Our group was terrified", one unidentified passenger told Seven News.

However, it is so far not known what exactly caused the mid-air emergency.

Thankfully none of the passengers or crew members got hurt and the plane landed safely at the Sydney airport after the mid-air emergency.

The Australia Transport Safety Bureau was starting an investigation and an update would normally be available within a month but could come sooner if a "more serious issue" was identified in its early stages, Bob Armstrong, a spokesman for the bureau said.

The aircraft's Trent 700 series engines were made by Rolls Royce, and a spokeswoman for the company said that they were "aware of the incident", and will be cooperating with their partners "to understand the cause of the issue".

China Eastern Airlines has been contacted for comment. Today the passengers will be arranged to fly to their destinations on either China Eastern flights or other airlines.

Photos of the incident showing a huge hole torn in the engine's cowling, or cover, are similar to those taken of the China Eastern plane. "It could have begun from loose screws", he told the Australian Broadcasting Corp.

But despite the dramatic scenes, Thomas said the damage was not as severe as the engine failure experienced by Qantas Singapore-Sydney flight QF32 in 2010 due to a separate problem, which led the Australian carrier to ground all its A380s.

Damage to the left engine of an Egypt Air A330 after takeoff in Cairo on May 17, 2017.