Joan Galbraith and Beverley Moyle's brother Flight Lieutenant Graham Lucas was a pilot on the DC10 which crashed into the Antarctic mountain 30 years ago, killing all 257 people on board.
Fl Lt Lucas (39) had flown the plane for the first leg of the journey to the ice, where another pilot took over.
Mrs Galbraith was her brother's next of kin in the case of an accident and took the call informing the family he had died.
She was in contact with Air New Zealand a few more times before the last contact with the family was made a year later in 1980.
Since then, the Lucas family has heard nothing from Air New Zealand, including no contact about a memorial service on Friday at which Air New Zealand chief executive Rob Fyfe unveiled a monument to the victims and apologised to their families for not receiving the compassion and support they should have.
The family was not represented at the service, because it had not been aware it was on, despite being easy to locate, Mrs Moyle said.
The sisters were aware from media reports of an Antarctic trip planned by Air New Zealand, but were not interested in that.
Mrs Moyle said she heard something about a memorial late last week, but did not know details.
Mrs Galbraith's address was the same as 30 years ago and the family was expecting her to find an invitation in her letterbox when she returned from an overseas holiday.
"But there wasn't."
By then, it was Saturday and too late anyway, they discovered.
"I just thought this one was special and it would have been nice to have him represented. We would definitely have been there if we had known. It was such a huge loss for all of us.
"This is the nearest they've come to having some feelings about the whole thing."
Mrs Moyle did not blame Mr Fyfe for the lack of communication.
"I'm quite impressed with Mr Fyfe - he inherited this mess.
"But there were only 20 Air New Zealand staff on board the DC10. It would not have been such a huge ask to contact their families.
"You only have to look in the white pages and my brother is the first Lucas in the book."
An Air New Zealand spokeswoman said 30 years later, people had moved on, changed names and remarried.
It was decided the best way to reach as many family members as possible was to publicise the events through the media.
The company had placed advertisements in the public notice sections of 26 newspapers nationwide asking relatives of Erebus victims to contact it.
It had also sent out two press releases, one containing information about the service.
