A third Qantas flight has been forced to make an unscheduled landing.
Qantas said flight QF7, en route to Dallas from Sydney, returned four hours after take-off due to a technical issue affecting seat power, the in-flight entertainment system and some toilets.
The A380 was the third Qantas flight to make an unscheduled landing in less than 24 hours, the ABC reports.
A statement from Qantas said the decision to return to Australia was based on passenger comfort.
On Monday afternoon, a flight from Perth to Karratha was turned back after a strong odour was detected. The pilot of the 737 aircraft called for emergency landing protocols after smoke was detected in the cabin.
About 80 passengers were assessed by St John Ambulance staff over concerns about smoke inhalation but no-one was taken to hospital.
Earlier in the day another A380 jet, travelling from Dubai to Sydney, made an emergency landing in Perth after developing an air conditioning fault while flying over the Indian Ocean.
"As a precaution the aircraft descended to 10,000 feet and the captain requested a priority landing," Qantas said in a statement. Nobody was injured.