The podcast and video series Erebus Flight 901: Litany of Lies? runs on nzherald.co.nz on weekdays from Monday November 18 to Thursday November 28, the 40th anniversary of the Erebus disaster. You can listen to all the episodes in the NZ On Air-funded series in the iHeart player below or catch up on all our coverage of the disaster at nzherald.co.nz/erebus
Air New Zealand did not reveal crucial flight path evidence which would have confirmed it told "an orchestrated litany of lies" at the Royal Commission of Inquiry into the Erebus disaster, says a judge involved in the inquiry.
Judge Gary Harrison, who worked on the inquiry as a young lawyer, said board minutes later showed the company knew from the start that its planes did not normally fly over Mt Erebus.
He said the evidence came too late to support Justice Peter Mahon's hugely controversial statement that Air New Zealand witnesses told him "an orchestrated litany of lies" at the inquiry - "although it confirmed belatedly, that he was correct".
The evidence is important because it strongly suggests Air New Zealand knew its pilots were expecting to fly safely down McMurdo Sound, well clear of Mt Erebus, contrary to its official position at the inquiry.
The crash - which occurred 40 years ago today - happened after the airline changed the flight path coordinates from McMurdo Sound to line up with Mt Erebus, without telling the pilots.
The crew never saw the mountain in front of them because it was hidden by an optical illusion caused by polar whiteout conditions.
The original report on the crash by the Chief Inspector of Air Accidents Ron Chippindale effectively blamed pilot Jim Collins and co-pilot Greg Cassin for flying too low in cloudy conditions.
But Justice Peter Mahon's inquiry found Air New Zealand was to blame and famously accused the airline of telling him "an orchestrated litany of lies".
Harrison, who assisted Mahon and is now a District Court judge, told the makers of the Herald's 40th anniversary podcast Erebus Flight 901: Litany of Lies? that Air New Zealand never told the inquiry that its own board minutes strongly suggested it knew the aircraft was well off the expected McMurdo Sound track, which was also a route used by US military aircraft.
Harrison said the company secretary and Air New Zealand board deputy chairman Des Dalgety took notes of chief executive Morrie Davis' briefing to directors at the board's first meeting after the crash on December 7.
"And both the secretary's notes and Mr Dalgety's notes recorded Mr Davis telling them the impact position was considerably left of track, which is astonishing, because that meant he had been told, for that first meeting of directors, that the impact position was considerably left of the military track, which was 27 miles to the west of the impact position.
"We were never told that's what Mr Davis told his directors at that first meeting. And subsequent to that, they always insisted the route went over the top of the mountain.
"If we had known that, that would have been a crucial piece of evidence in cross-examining those three individuals."
Harrison said the minutes emerged in the legal discovery process for the Court of Appeal hearing but as the information had not been presented to the inquiry, it could not be used to support Mahon's claim that the company had pursued a "predetermined plan of deception" in its evidence.
A spokeswoman for Air New Zealand said the airline did not wish to comment.
Erebus historian Stuart MacFarlane, author of The Erebus Papers, said he was aware of the board minutes, which he described as important.
Following a legal challenge by Air New Zealand, the Court of Appeal and later the Privy Council ruled that Mahon was wrong to accuse the airline of "an orchestrated litany of lies" but did not overturn his findings on the cause of the crash.