werbil,
"To condemn the crew based on the weather in another location (even if it was their eventual destination) is irrelevant."
Considering Mt Erebus was hiding amongst this weather your statement of irrelevance is to say the least puzzling.
" It is the company's responsibility to ensure that the flight crew are route qualified"
If you have been following this thread you will no doubt have noticed that it was demanded, requested , or at any rate required from NZALPA that their members all be given a turn on this perk flight to the Antarctic. This in complete disregard of the experience in Antarctic operations demanded by all other operators going down there, RNZAF, USAF, USN, etc. While this may be seen as a fault of the company surely it must also be considered when blame is apportioned for this event.
It was not, as has been described by NZ's most experienced Antarctic operator, a Sunday drive, with up to 11 people believed to be in the cockpit at the critical time.
"limitations of weather radar for ground mapping of surfaces covered by dry snow, the alteration of the waypoints combined with the ambiguity [polite way to put it] of the route in relation to Mt Erebus)."
That is a theory of Mahons, it is not held by everybody, and there was certainly plenty of rock faces to give a good return from Beaufort Island, and as has been said many times Beaufort Island, if they were on the track they thought they were on, was on the wrong side.
By going VMC descent they took responsiblity for their own terrain clearance, they impacted terrain, how can that impact then be seen as anybody elses failing??? They were well aware of their lack of Antarctic experience, surely one would be ultra careful, and not do such things as design own descent procedure in marginal weather in that location.