A Qantas A380 bound for London was forced to land in Dubai on Friday after an engine fault.
Qantas said the Airbus aircraft had an "oil quantity defect" in one engine which was switched off according to standard procedure. Qantas engineers would investigate the problem, a spokeswoman for the airline said. The plane with 258 people on board landed safely in Dubai.
In November 4 last year a Qantas Airbus A380 aircraft suffered an engine explosion after it had taken off from Singapore for Sydney. It returned to Singapore and landed safely.
"The two issues are completely unrelated. This is a one-off and we will look to get the aircraft back in the skies as soon as possible," spokeswoman Olivia Wirth said, referring to the latest incident and the engine explosion a year ago.
Each Qantas A380 is powered by four Rolls Royce engines. The carrier has 10 A380s in service and is due to take delivery of two more by year-end. It also has two more on order and deferred the delivery schedule for six others.
"We are aware that an A380 operated by Qantas diverted to Dubai as a precautionary measure. We are working with the airline to look into this matter," Airbus spokesman Sean Lee said.
Airbus has sold 236 A380s. By the end of September this year, it had delivered 57. The four-engined double-decker airplanes sell for $375 million each at list prices.
A Rolls Royce spokesman said the company was aware of the incident and was working closely with Qantas to provide appropriate support and technical assistance.
In last year's engine blowout, a turbine disc disintegrated and sent supersonic shards of metal through the aircraft's wing, severing systems and narrowly missing the cabin. Investigations have pinpointed a suspected manufacturing fault in an oil pipe which could lead to oil leaks and ordered regular safety checks.
Rolls-Royce, which competes with a General Electric and Pratt & Whitney joint venture to power the A380, says it has solved the problem and replaced or upgraded engines.
Rolls Royce engines power the A380 fleet of Qantas, Singapore Airlines, and Lufthansa and China Southern.
Qantas resumed A380 services on November 27 after engine inspections concluded the airplane was safe to fly.
The latest incident follows a series of setbacks for Qantas, which is emerging from the grounding of its entire fleet over the weekend to gain the upper hand against trade unions in a long-running and costly labour dispute. The weekend shutdown stranded almost 70,000 passengers but succeeded in forcing the government and the nation's labour tribunal to intervene and ban all further strikes at Qantas.