The son of a drunk New Zealand grandmother who punched a passenger in the face during a transtasman flight says the episode has been embarrassing for the family.

Frances Macaskill's son, who lives in Perth, said he had not spoken to his mother for more than a year.

Kevin Macaskill said his mother had a drinking problem that had caused tension in the family for years.

Macaskill, 58, was yesterday ordered to pay Qantas A$18,245 ($23,500), the amount she cost the airline when her behaviour resulted in the Wellington-bound flight turning back to Melbourne on Saturday.


She has been banned from flying with Qantas, and associates Jetstar and Jetconnect, for at least 10 years.

In the Melbourne Magistrate's Court yesterday, Magistrate Luisa Bazzani ordered Macaskill to pay restitution to the airline, fined her an additional A$3500 and sentenced her to four months' jail, suspended for two years.

Macaskill pleaded guilty to one charge of offensive and disorderly behaviour on an aircraft and one charge of assault.

"I believe she didn't know what she was doing, but she's got to take responsibility," Kevin Macaskill said.

"She obviously has a problem [with alcohol]. We've tried to do things over the years.

"I don't know what to say - hopefully this will help her realise she has to change her ways."

He said he would wait until publicity over his mother's court case had died down before he contacted her.

Qantas Group's head of security, Steve Jackson, said the crew who restrained Macaskill had acted "extremely bravely".

"This person injured an innocent passenger and caused significant inconvenience for other passengers who were five hours late getting to their destination."