As an outside observer, and non-pilot, the Mahon report created an interesting perspective on the use of 'company culture' for the basis of determining the cause of the accident.
I've spent much of the day watching - and re-watching - numerous documentaries, research and interviews regarding the Erebus tragedy, as someone who wasn't born when it happened. I'm no expert - nor am I a pilot - so my comments aren't as informed as most on here. However, I have several questions I hope others can help me with:
Note: No judgement on anyone is cast in my post here!
1) While the Chippendale report certainly raised the fact that flying below MSA was the 'cause', it was Mahon's enlarged scope that brought the lack of checks and balances within Air NZ to the fore. It was raised in one of the documentaries (Flight 901 to Erebus) that there had been many documented instances in the media, and in Air NZ's own publicity material, where flights were conducted below MSA. Other pilots - prior to Erebus - had done this as well.
Is it not then feasible - given the circumstances - that 'company culture' played a role in shaping the actions of the crew, not just in the realm of this accident, but in prior Antarctic flights as well? Evidence and submissions showed many contradictions in terms of what expectations and rules crew were to follow.
2) The differences in scope of the investigation (Chippendale vs. Mahon's findings) - as have been noted on here - draw the distinction of a pilot vs. non-pilot making technical judgements in an aviation investigation. However, were it not for Mahon's findings, the many managerial and technical flaws that existed in Air NZ would never have come to light. Also, this breadth of investigation, from my own personal research, seems evident in other accident investigations around the world.
Pure conjecture, but it must be asked: If we relied on the findings of the Chippendale report, without questioning further, would we not be arguing instead about another accident occurring at Air NZ? Another incident involving a flightplan error - however, with the benefit of the lessons of Erebus - was caught on an AKL-RAR flight (termed the '4th December Incident' - had never heard of it before, in the sphere of the Erebus investigation).
I believe it occurred some 8-months after the RC ended?
3) Recently in this forum, much has been made of the Bendix weather radar, and its' ability to pick up ice, etc. The manual for the type of radar installed on the aircraft stated it should not be used for terrain avoidance. Aside from the GPWS (sadly), what other radar systems could the crew have used at the time? Just seems to be disagreement within the forum (not unusual, I know).