Qantas engineers are examining an A380 jet that was forced to make an emergency landing in Perth.

Qantas Flight QF2 travelling from Dubai to Sydney was diverted to Perth early on Monday due to a fault in its air conditioning system, after the plane descended to 10,000 and the captain requested a “priority landing” at the airport.

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The incident started about 3am over the Indian Ocean, around 700km northwest of Perth.

A Qantas spokesman said the super jumbo, which landed safely, was being inspected.

“It was a fault with the air conditioning so the engineers are having a look at that now,” he said.

“It’s taking a little bit of time to get to the bottom of it.”

The jumbo is expected to return to Sydney later on Monday.

“It will fly back empty,” the spokesman said.

Passengers who were onboard have been given accommodation and would be booked on upcoming services to their destinations.

During the flight, passenger Nigel Richardson tweeted pictures from the cabin showing all was calm.

“Full shut down of air conditioning system that keeps plane pressurised at altitude was the problem,” he said in a post.

Mr Richardson praised the response of the crew saying “#qantas first officer walking through plane giving personal situation update to everyone as best he can. Full marks to crew #QF2”.

A Qantas passenger flight from Sydney to Dubai has made an emergency landing in Perth after experiencing problems with cabin air pressure.

A spokesperson for the airline said flight QF2 made the early morning emergency landing after the plane’s air conditioning, which keeps the plane pressurised, failed.

Plenty of passengers (self included) waiting to get off #qantas #QF2 Staff working on logistics for us all. Qantas comms still excellent.

— Nigel Richardson (@NigelRichardson) December 7, 2014

Words you don’t expect to hear while on a plane “Cabin crew this is an emergency descent” #qantas #qf2 — Nigel Richardson (@NigelRichardson) December 7, 2014

Fastest descent I’ve ever experienced in a plane. Always interesting when you see cabin crew running too…#qantas #qf2 — Nigel Richardson (@NigelRichardson) December 7, 2014

Air conditioning problem. Aircraft not in danger. Crew very calm and professional. #qantas #qf2 — Nigel Richardson (@NigelRichardson) December 7, 2014

Emergency vehicles on site at landing as precaution. Crew calm and reassuring but some very nervous passengers on board #qantas #qf2 — Nigel Richardson (@NigelRichardson) December 7, 2014

Full shut down of air conditioning system that keeps plane pressurised at altitude was the problem. #qantas #qf2 — Nigel Richardson (@NigelRichardson) December 7, 2014

All calm on board #qantas #qf2 pic.twitter.com/CEKUu0eGi8 — Nigel Richardson (@NigelRichardson) December 7, 2014