A Qantas flight bound from Sydney to Perth has been forced to turn around and make an sudden landing at Mascot on Monday morning.

Emergency services scrambled at Sydney Airport after the flight did a u-turn and headed back to it’s departure point after smoke was detected in the cockpit.

A Qantas spokesperson said the smoke did not enter the cabin.

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The captain subsequently made a priority landing, minutes after takeoff.

“Our pilots are highly trained to handle situations like this and the aircraft landed safely after the appropriate procedures were conducted,” they said.

“We understand this would have been an unsettling experience for customers and apologise for the inconvenience.

“Our engineers will be checking the aircraft today and we will be conducting an investigation into what caused the issue.”

QF643, a Boeing 737, made a loop over the ocean off Sydney after its altitude peaked at 3960 metres.

The aircraft landed safely and taxied back to the gate under it’s own steam.

The aviation news outlet AviationSource reported a ‘code 7700’ which is an indication a flight needs immediate support from air traffic control had taken place.

An additional flight has been provided for customers which is scheduled to depart Sydney at 11:30am on Monday.