Air Force Chief Geoff Brown has thrown doubt on the effectiveness of Environment Minister Greg Hunt's switch to using aircraft to monitor Antarctic whaling.

"The [Airbus] A319 is not suitable for that task," Air Marshall Brown told a Senate estimates hearing on Wednesday.

Air Marshal Geoff Brown. Credit:Brockwell Perks

"The word surveillance can mean many things," he said. "Surveillance out of a passenger aeroplane is a pretty limited operation."

He said the Air Force considered all options for the whaling surveillance task, including its P3 Orion and C-17 Globemasters, but found them unsuitable because they lacked the range to operate off the Antarctic coast.