Australia's Civil Aviation Safety Authority (CASA) says it is increasing its surveillance of offshore maintenance of Qantas aircraft.

The airline has had a spate of safety incidents in recent months.

But the authority has told a Senate estimates committee that it is happy with the current standards for offshore maintenance.

CASA's Mick Quinn says the authority is enhancing the scope of surveillance as a result of the airline's heavier reliance on offshore outsourcing.

"Previously we used to audit specifically the heavy maintenance bases, we've now taken that a step further and now looking at the line maintenance facilities across the network," he said.

"Obviously we don't have the ability to look at the entire network, but obviously selecting a few key points where the sort of maintenance is done in turnarounds is conducted, and CASA's added that to its surveillance."