New Zealand's Prime Minister Jacinda Ardern said the government's handling of the 1979 air disaster's aftermath was wrong (AFP Photo).

WELLINGTON, New Zealand (AFP) — Prime Minister Jacinda Ardern offered an official apology Thursday on the 40th anniversary of New Zealand’s worst peacetime disaster, the Mount Erebus air crash in which 257 people died.

An Air New Zealand DC-10 on a sightseeing flight over Antarctica slammed into remote Mount Erebus during “whiteout” conditions on the frozen continent on 28 November 1979, killing all on board.

“That loss, in and of itself, was huge. It sent ripples across the country… but that loss and grief was compounded. It was undeniably worsened by the events that followed,” Ardern told a commemoration service in Auckland.

An initial inquiry blamed pilot error but a royal commission, the most powerful judicial inquiry under New Zealand law, subsequently cleared the crew.

It found the airline reset the plane’s navigation systems without telling the pilots, inadvertently setting the aircraft on a collision course with the side of the mountain.

The report’s author, judge Peter Mahon, also accused Air New Zealand officials of telling “an orchestrated litany of lies” to cover up the mistake and keep the blame on the pilots.

The then prime minister Robert Muldoon attacked Mahon’s report, viewing the findings against the state-owned carrier as a blow to national prestige, and it was not formally tabled until 1999, 18 years after its completion.

Ardern said the government’s handling of the disaster’s aftermath was wrong.

“It caused trauma on top of grief. And persecution on top of pain,” said the prime minister, who at 38 was not born when the crash occurred.