The glitch was the third time in two months when an A380, the world's biggest passenger airliner, was delayed due to a fuel issue.

'Tonight's flight to Sydney, SQ221, will incur a delay of about one hour while some rectification work is done on a fuel line that carries fuel between the respective tanks,' SIA spokesman Stephen Forshaw said in a statement to AFP before the plane took off.

He gave no further details.

Singapore's Changi Airport flights website showed SQ221, originally scheduled to depart at 8:30 pm, took off from Terminal 3 for Sydney at 9:50 pm.

Another SIA Airbus A380 was forced to cancel a flight to Sydney earlier this week because of a defect in the fuel pump, the carrier said Wednesday.

In January, SIA grounded another A380 flight after it became unhinged from a tow truck and accidentally touched grass on the side of the tarmac.

SIA acquired its first A380 in October last year, becoming the first airline to operate the double decker aircraft with the launch of commercial services from Singapore to Sydney in the same month.

The jet, as tall as a seven-storey building and with about 50 percent more cabin space than its rivals, was carrying 449 passengers enjoying increased legroom and state-of-the-art in-flight entertainment.

The airline began commercial flights to London on the A380 on March 18. -- AFP