A passenger onboard the plane that sent out an initial mayday call has detailed what happened on the flight when one of its engines failed an hour before it was due to arrive in Sydney.

Nigel Morris told The Today Show he didn’t hear anything but the plane jolted significantly and began to turn off course during the trip.

“I didn’t hear a bang but there was a major jolt and the plane banked mid-flight,” he said.

“I think everyone was immediately aware there was something happening.”

Mr Morris said the pilot didn’t let on there was a massive issue with the plane until the landing announcement once the flight — which had 145 passengers on it — was taxiing on the tarmac at Sydney airport.

“The pilot said, ‘We had an issue mid-flight. We lost some functions with one of the engines and we’re going to land on the field so that emergency services can take a look at the engine,’ so that’s what we did,” he said.

Passengers only really began to realise the severity of the problem when they turned their phones back on after the trip.

“When we landed and the cabin crew said, ‘You can turn on your phones’ I turned mine on and there were lots of messages and calls from [my wife] saying ‘Oh, my god, what’s happening?’,” Morris said.

“There was a surge of adrenaline through the plane, a bit of a buzz when people realised it was a lot more serious than we understood at the time.”

Just reading that is making the hair on the back of my neck stand up and my legs feel all funny. Suddenly being whacked with the knowledge of being inches from shit seriously hitting the fan would have shot my heart rate through the roof.

Hundreds of thousands of people were watching flight tracking maps on Wednesday afternoon after a Qantas flight sent an emergency message to Sydney airport while flying over from New Zealand.

The mayday alert was later downgraded to “possible assistance needed” (PAN) and the plane was able to land safely on the tarmac where several paramedics and firetrucks were waiting to assist.

A Qantas spokesperson has confirmed the plane being assessed by engineers to determine how one engine failed mid-flight.

Image: Getty Images / Brendon Thorne