A probe has been launched after a shocking near miss between two Qantas aircrafts on Sydney Airport's main runway. The Australian Transport Safety Bureau has confirmed an investigation is underway following an incident last week, which almost resulted in a catastrophe. On July 27, air traffic control gave clearance for a Boeing 737 Qantas flight from Canberra to cross between runways at the airport. A Qantas spokesman said that both pilots were acting with permission. "Both Qantas aircraft were cleared to proceed following instructions from air traffic control and we will support the ATSB in the investigation," the spokesman said.