Australian airlines must have two crew members in the cockpit at all times, under a deal struck with the industry after the Germanwings plane crash.
The pilot of the plane, which is believed to have been deliberately crashed into the French Alps, was locked out of the cockpit by his co-pilot.
Domestic and international airlines will have to comply with the new rule immediately, Transport Minister Warren Truss announced on Monday.
Standard operating procedure will require two members of the operating crew, or authorised people, on the flight deck at all times.
The rule will apply at all times to all regular passenger transport services where the aircraft has seating capacity for 50 passengers and above.
Mr Truss says aviation agencies will work with the industry and airline staff on further improvements, such as the requirements for medical testing, including mental health, of all flight crew members.
“Today’s decision is a sensible, measured response that combines safeguarding the travelling public with the practical capabilities of the aviation sector,” he said.
The Germanwings flight crashed on Tuesday, killing all 150 people on board, including Australians Carol Friday, 68, and her son Greig, 29.
Australian pilots are already subject to annual medical reviews, which include a psychiatric assessment.
If at any time there are concerns about the mental health of any pilot or co-pilot they are not placed in command of aircraft.
Qantas said in a statement it would have two approved people in the cockpit at all times in-flight.
When one pilot needs to leave the cockpit for any reason, another authorised person will occupy the jump seat – as distinct from the control seats occupied by the captain and first officer – until they return.
Qantas said it offered regular medical checks, stress management training, confidential counselling and pilot-to-pilot support networks.
Virgin said it would also adhere to the policy.
Australian and International Pilots Association president Nathan Safe told AAP he was not convinced the new policy would have prevented the Germanwings crash.
“But we understand it is important the government acts and treats safety as its most important consideration,” he said.
Greens transport spokeswoman Janet Rice said it was a stopgap measure and the answer lay in providing greater resources for support services and ensuring airlines took a “mature approach” to the mental health of employees.
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