Judgments of the Court of Appeal of New Zealand on Proceedings to Review Aspects of the Report of t | Page 3

the ground computer the entry was altered to 166�� 58' east, and this entry was among the many in the flight plan handed over to the crew for that flight for typing into the computerised device (AINS) on board the aircraft. The change was not expressly drawn to the attention of the crew. The AINS enables the pilot to fly automatically on the computer course ('nav' track) at such times as he wishes.
The crash occurred at 12.50 pm on 28 November 1979. The aircraft struck the northern slopes of Mount Erebus, only about 1500 feet above sea level. There were no survivors. The evidence indicates that the weather was fine but overcast and that the plane had descended below the cloud base and was flying in clear air. The pilot, Captain Collins, had not been to the Antarctic before, and of the other four members of the flight crew only one, a flight engineer, had done so. The plane was on nav track.
The Chief Inspector of Air Accidents, Mr R. Chippindale, carried out an investigation and made a report to the Minister, dated 31 May 1980, under reg. 16 of the Civil Aviation (Accident Investigation) Regulations 1978. It was approved by the Minister for release as a public document. The Chief Inspector concluded that 'The probable cause of the accident was the decision of the captain to continue the flight at low level toward an area of poor surface and horizon definition when the crew was not certain of their position and the subsequent inability to detect the rising terrain which intercepted the aircraft's flight path'. He adhered to this in evidence before the subsequent Royal Commission.
The Royal Commission was appointed on 11 June 1980 to inquire into 'the causes and circumstances of the crash', an expression which was elaborated in terms of reference consisting of paragraphs (a) to (j). Mr. Justice Mahon was appointed sole Commissioner. In his report, transmitted to the Governor-General by letter dated 16 April 1981 and subsequently presented to the House of Representatives by Command of His Excellency and later printed for public sale, the Commissioner found that '... the single dominant and effective cause of the disaster was the mistake made by those airline officials who programmed the aircraft to fly directly at Mt. Erebus and omitted to tell the aircrew'. He exonerated the crew from any error contributing to the disaster.
The Commissioner and the Chief Inspector were at one in concluding that the crash has occurred in a whiteout. The Commissioner gave this vivid reconstruction in the course of para. 40 of his report:
I have already made it clear that the aircraft struck the lower slopes of Mt. Erebus whilst flying in clear air. The DC10 was at the time flying under a total cloud cover which extended forward until it met the mountain-side at an altitude of somewhere between 2000 and 2500 feet. The position of the sun at the time of impact was directly behind the aircraft, being in a position approximately to the true north of the mountain and shining at an inclination of 34��. The co-existence of these factors produced without doubt the classic 'whiteout' phenomenon which occurs from time to time in polar regions, or in any terrain totally covered by snow. Very extensive evidence was received by the Commission as to the occurrence and the consequences of this weather phenomenon. So long as the view ahead from the flight deck of an aircraft flying over snow under a solid overcast does not exhibit any rock, or tree, or other landmark which can offer a guide as to sloping or uneven ground, then the snow-covered terrain ahead of the aircraft will invariably appear to be flat. Slopes and ridges will disappear. The line of vision from the flight deck towards the horizon (if there is one) will actually portray a white even expanse which is uniformly level.
What this air crew saw ahead of them as the aircraft levelled out at 3000 feet and then later at 1500 feet was a long vista of flat snow-covered terrain, extending ahead for miles. Similarly, the roof of the solid overcast extended forward for miles. In the far distance the flat white terrain would either have appeared to have reached the horizon many miles away or, more probably, merged imperceptibly with the overhead cloud thus producing no horizon at all. What the crew could see, therefore, was what appeared to be the distant stretch of flat white ground representing the flat long corridor of McMurdo Sound. In reality the flat ground ahead proceeded for only about 6 miles before it intercepted the low ice cliff which marked the commencement of the icy slope leading upwards to the mountain, and at that point the uniform white surface of the mountain slope proceeded upwards,