" There is no evidence that he descended through cloud, in fact there is no evidence that he didn't maintain VMC at all times"
And there is no evidence that he did. I use he rather than they because there was no consultation with the rest of the crew as to his intentions on descent.
There is the weather report from McMurdo, with very well qualified met observers that advised the crew the area was no good for sightseeing due weather, even stating that the tops of local hills were above the cloud base, there are the reports from the USAF aircraft that followed a little while behind about the layers of cloud they descended through..
From John King publication.
From 1978 until the disaster all those pilots had cheerfully flown down McMurdo Sound more or less on the approach path used by the military pilots, instead of over Ross Island. The former might have seemed the more logical route, keeping clear of high ground, but the airline preferred it's DC10's to stay well away from any conflicting local traffic.In any case it was largely academic as all but one flight had approached Antarctica in brilliantly clear conditions and the final letdown was entirely VFR with no need for instrument cloud break procedures.
The one exception was Captain Roger Dalziells's flight which, because of unfavourable McMurdo weather took the alternative sightseeing route over the South Magnetic Pole, diverting even before reaching the specified decision point of Cape Hallett.
So obviously the weather was the deciding factor, and on his first venture down to the ice, the captain took it upon himself to completely disregard advice from seasoned Antarctic weather observers as to the advisability of proceeding to McMurdo Base.
But this decision, according to Justice Mahon, was not the deciding factor that ended up with the aircraft impacting Ross Island at slightly under 1,500ft.
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