Two international Qantas flights leaving Kingsford Smith Airport in Sydney have been forced to turn back on Friday, after mid-air mechanical problems.
Airbus A380 QF7, en route to Dallas Fort Worth in the United States was detected dumping fuel and circling the airport by air traffic control.
"The flaps on the aircraft (attached to the wing) are unable to retract which means the aircraft can't fly efficiently," Qantas said in a statement.
"As the Dallas flight is our longest on the network, the captain made the decision to return to Sydney."
Earlier, Boeing 747 QF63 from Sydney to Johannesburg also had to turn around and perform an emergency landing, however it has not yet been made clear what the fault was with the aircraft.
"Our operational teams are working through accommodating passengers or offering them transport home before replacement services are organized," Qantas said.