first at an angle of 13��, and then with a gradually increasing upward angle as it merged with the ceiling of the cloud overhead. The only feature of the forward terrain which was not totally white consisted of two small and shallow strips of black rock at the very bottom of the ice cliff, and these could probably not be seen from the flight deck seats owing to the nose-up attitude of 5�� at which the aircraft was travelling, or they were mistaken for thin strips of sea previously observed by the crew as separating blocks of pack ice.
The aircraft had thus encountered, at a fateful coincidence in time, the insidious and unidentifiable terrain deception of a classic whiteout situation. They had encountered that type of visual illusion which makes rising white plateaux appear perfectly flat. This freak of polar weather is known and feared by every polar flier. In some Arctic regions in the Canadian and in the north European winter, it is responsible for numbers of light aircraft crashes every year. Aircraft fly, in clear air, directly into hills and mountains. But neither Captain Collins nor First Officer Cassin had ever flown at low altitude in polar regions before. Even Mr Mulgrew [the commentator for the passengers], with his antarctic experience, was completely deceived. The fact that not one of the five persons on the flight deck ever identified the rising terrain confirms the totality of this weird and dangerous ocular illusion as it existed on the approach to Mt. Erebus at 12.50 p.m. on 28 November 1979.
Paragraph 165 of the Commissioner's report also merits quotation. We have underlined some of it, indicating that in this particular part of his report the Commissioner seems to accept that when they first heard of the crash the management of the airline must have been unaware of the true nature and danger of a whiteout. If so, they would have had no reason to suppose that the pilot would have elected to fly at such a low level without real visibility. That is an aspect which could well have been strongly relied on if, when giving evidence before the Commissioner, they had realised that they were being accused of trying to cover up the cause of the crash from an early stage:
The term 'whiteout' has more than one meaning as being descriptive of weather conditions in snow-covered terrain. For aviation purposes it is often described as the cause of the visual difficulty which occurs when a aircraft is attempting to land during a snowstorm. As already stated, the United States Navy maintains a special whiteout landing area situated to the south of its normal landing strips near McMurdo Station. This area is used when an aircraft, which is committed to a landing, is required to land when visibility is obscured by a snowstorm. The snow in Antarctica is perfectly dry, and a wind of only 20 kilometres can sweep loose snow off the surface and fill the air with these fine white particles. A landing on the special whiteout landing field can be accomplished only by an aircraft equipped with skis or, in the case of an aircraft without skis, then it must make a belly-up landing on this snow-covered emergency airfield. Flying in a 'whiteout' of that description is no different from flying in thick cloud. The pilot cannot know where he is and must land in accordance with strict radio and radar directions. So far as I understand the evidence, I do not believe that either the airline or Civil Aviation Division ever understood the term 'whiteout' to mean anything else than a snowstorm. I do not believe that they were ever aware, until they read the chief inspector's report of the type of 'whiteout' which occurs in clear air, in calm conditions, and which creates this visual illusion which I have previously described and which is, without doubt, the most dangerous of all polar weather phenomena.
While largely agreed about the whiteout conditions, the Commissioner and the Chief Inspector took quite different views as to whether the crew had been uncertain of their position and visibility. This disagreement is associated with a major difference as to the interpretation of the tape recovered from the cockpit voice recorder covering the conversation on the flight deck during the 30 minutes before the crash.
Both the Commissioner and the Chief Inspector found difficulty in arriving at an opinion about what was said and by whom. Whereas the Chief Inspector thought that the two flight engineers had voiced mounting alarm at proceeding at a low level towards a cloud-covered area, the Commissioner thought that Captain Collins and First Officer Cassin had never expressed the slightest doubt as to where the aircraft was and that 'not one word' was ever addressed by either of the
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