The Australian family of a mother and son killed in the Germanwings air crash has spoken of their loss.

Carol and Greig Friday were among the 150 people who died when their Airbus A320 slammed into the French Alps.

Australia correspondent Donna Demaio told Newstalk ZB's Rachel Smalley Carol Friday had gone over to Europe to spend a few weeks on holiday with her son.

"She was described as a talented artist, she was a regular nurse, she'd done a lot of work with her local art group and she was one of those people who was always there to welcome new neighbours and to help someone in need."

Meanwhile, French air investigators have ruled out a mid-air explosion as a cause of the crash.

The BEA says the trajectory of the plane indicates it flew right to the point of the crash...or at least some metres close to it.

It adds the spread and size of the debris also confirms this idea.

It could take some weeks or even months before the exact cause of the accident can be confirmed.