Mount Erebus disaster
The Mount Erebus disaster occurred on 28 November 1979 when Air New Zealand Flight 901 flew into Mount Erebus on Ross Island, Antarctica, killing all 237 passengers and 20 crew on board. Air New Zealand had been operating scheduled Antarctic sightseeing flights since 1977. This flight left Auckland Airport in the morning and was supposed to spend a few hours flying over the Antarctic continent, before returning to Auckland in the evening via Christchurch.
The initial investigation concluded the accident was caused primarily by pilot error, but public outcry led to the establishment of a Royal Commission of Inquiry into the crash. The commission, presided over by Justice Peter Mahon, concluded that the accident was primarily caused by an automatic correction made to the coordinates of the flight path the night before the disaster, coupled with a failure to inform the flight crew of the change, with the result that the aircraft, instead of being directed by computer down McMurdo Sound, was instead rerouted to a path toward Mount Erebus. Justice Mahon's report accused Air New Zealand of presenting "an orchestrated litany of lies", and this led to changes in senior management at the airline. The Judicial Committee of the Privy Council later ruled that the finding of a conspiracy was a breach of natural justice and not supported by the evidence.
The accident is the deadliest in the history of Air New Zealand, the deadliest aviation accident in Antarctica, and New Zealand's deadliest peacetime disaster.
Category:Filmed deaths during aviation accidents and incidents
Flight and aircraft
Flight 901 was designed and marketed as a unique sightseeing experience, carrying an experienced Antarctic guide, who pointed out scenic features and landmarks using the aircraft's public-address system, while passengers enjoyed a low-flying sweep of McMurdo Sound. The flights left and returned to New Zealand the same day. The plane left Auckland International Airport at for Antarctica, and was scheduled to arrive back at Christchurch International Airport at after flying. The aircraft would make a 45-minute stop at Christchurch for refuelling and a crew change, before flying the remaining to Auckland, arriving at. Tickets for the November 1979 flights cost per person. Dignitaries including Sir Edmund Hillary had acted as guides on previous flights. Hillary was scheduled to act as the guide for the fatal flight of 28 November 1979, but had to cancel because of other commitments. His long-time friend and climbing companion, Peter Mulgrew, stood in as guide.The aircraft used for Antarctic flights were Air New Zealand's eight McDonnell Douglas DC-10-30 trijets. The aircraft on 28 November was registered ZK-NZP.
The 182nd DC-10 to be built, and the fourth DC-10 to be introduced by Air New Zealand, ZK-NZP was handed over to the airline on 12 December 1974 at McDonnell Douglas's Long Beach plant. It had logged more than 20,700 flight hours prior to the crash. Captain Thomas James "Jim" Collins, age 45, was an experienced pilot who had accumulated 11,151 flight hours, including 2,872 hours in the DC-10. First Officer Gregory Mark "Greg" Cassin, age 37, had accumulated 7,934 flight hours, including 1,361 in the DC-10. Flight Engineer Gordon Barrett Brooks, age 43, had 10,886 flight hours, including 3,000 in the DC-10. Also on board were First Officer Graham Neville Lucas, age 39, and Flight Engineer Nicholas John "Nick" Moloney, age 44. Flight Engineer Moloney had a total of 6,468 flight hours, including 1,700 in the DC-10.
Accident
All times are in New Zealand Standard Time, as at McMurdo Base. Mainland New Zealand was running on New Zealand Daylight Time at the time of the crash.Circumstances surrounding the accident
Captain Collins and co-pilot Cassin had never flown to Antarctica before, but they were experienced pilots and were considered qualified for the flight. On 9 November 1979, 19 days before departure, the two pilots attended a briefing in which they were given a copy of the previous flight's flight plan.The flight plan had been approved in 1977 by the Civil Aviation Division of the New Zealand Department of Transport and was along a track directly from Cape Hallett to the McMurdo non-directional beacon, which, coincidentally, entailed flying almost directly over the peak of Mount Erebus. Due to a typing error in the coordinates when the route was computerised, however, the printout from Air New Zealand's ground computer system that was presented at the 9 November briefing corresponded to a southerly flight path down the middle of the wide McMurdo Sound, about to the west of Mount Erebus. The majority of the previous 13 flights had also entered this flight plan's coordinates into their aircraft inertial navigational system and flown the McMurdo Sound route, unaware that the route flown did not correspond with the approved route.
Captain Leslie Simpson, the pilot of a flight on 14 November and also present at the 9 November briefing, compared the coordinates of the McMurdo tactical air navigation system navigation beacon, and the McMurdo waypoint that his flight crew had entered into the inertial navigation system, and was surprised to find a large distance between the two. After his flight, Captain Simpson advised Air New Zealand's navigation section of the difference in positions. For reasons that were disputed, this triggered Air New Zealand's navigation section to update the McMurdo waypoint coordinates stored in the ground computer to correspond with the coordinates of the McMurdo TACAN beacon, despite this also not corresponding with the approved route.
The Air New Zealand navigation section changed the McMurdo waypoint co-ordinate stored in the ground computer system around on the morning of the flight from to. Crucially, the flight crew of Flight 901 was not notified of the change. The flight plan printout given to the crew on the morning of the flight, which was subsequently entered by them into the aircraft's INS, differed from the flight plan presented at the 9 November briefing and from Captain Collins' map mark-ups, which he had prepared the night before the fatal flight. The key difference was that the flight plan presented at the briefing corresponded to a track down McMurdo Sound, giving Mount Erebus a wide berth to the east, whereas the flight plan printed on the morning of the flight corresponded to a track that coincided with Mount Erebus, which would result in a collision with the peak if this leg were flown at an altitude less than.
The Air New Zealand computer program was altered so that the standard telex forwarded to American air traffic controllers at the United States Antarctic science facility at McMurdo Station displayed the word "McMurdo", rather than the coordinates of latitude and longitude, for the final waypoint. During the [|subsequent inquiry], Justice Mahon concluded that this was a deliberate attempt to conceal from the United States authorities that the flight plan had been changed, probably because it was known that US air traffic control would lodge an objection to the new flight path.
The flight had earlier paused during the approach to McMurdo Sound to carry out a descent, via a figure-eight manoeuvre, through a gap in the low cloud base while over water to establish visual contact with surface landmarks and give the passengers a better view. The flight crew either was unaware of or ignored the approved route's minimum safe altitude of for the approach to Mount Erebus, and in the sector south of Mount Erebus. Photographs and news stories from previous flights showed that many of these had been flown at levels substantially below the route's MSA. In addition, preflight briefings for previous flights had approved descents to any altitude authorised by the US ATC at McMurdo Station. As the US ATC expected Flight 901 to follow the same route as previous flights down McMurdo Sound, and in accordance with the route waypoints previously advised by Air New Zealand to them, the US ATC advised Flight 901 that it had a radar that could let them down to. The radar equipment did not pick up the aircraft, however, and the crew also experienced difficulty establishing VHF communications. The distance measuring equipment did not lock onto the McMurdo TACAN for any useful period.
Cockpit voice recorder transcripts from the last minutes of the flight before impact with Mount Erebus indicated that the flight crew believed they were flying over McMurdo Sound, well to the west of Mount Erebus and with the Ross Ice Shelf visible on the horizon, when in reality they were flying directly toward the mountain. Despite most of the crew being engaged in identifying visual landmarks at the time, they never perceived the mountain directly in front of them. About 6 minutes after completing a descent in visual meteorological conditions, Flight 901 collided with the mountain at an altitude around, on the lower slopes of the tall mountain. Passenger photographs taken seconds before the collision removed all plausibility of a "flying in cloud" theory, showing perfectly clear visibility well beneath the cloud base, with landmarks to the left and to the right of the aircraft visible.
Crash into Mount Erebus
Collins told McMurdo Station that he would be dropping to, at which point he switched control of the aircraft to the autopilot. Outside, a layer of clouds blended with the white snow-covered volcano, forming a sector whiteout – no contrast between ground and sky was visible to the pilots. The effect deceived everyone on the flight deck, making them believe that the white mountainside was the Ross Ice Shelf, a huge expanse of floating ice derived from the great ice sheets of Antarctica, which was in fact now behind the mountain. Whiteout was little understood, even by the company’s experienced polar pilots—Air New Zealand had provided no training for the flight crew on the sector whiteout phenomenon. Consequently, the crew thought they were flying along McMurdo Sound, when they were actually flying over Lewis Bay in front of Mount Erebus.At 12:49 pm, the ground proximity warning system began sounding a series of alarms that began with two "whoop" tones followed by an audible command, "Pull up!", warning that the plane was dangerously close to terrain. The CVR recorded the following:
The captain had ordered a terrain escape manoeuvre by requesting the flight engineer apply full engine power, but it was too late. Six seconds later, the plane crashed into the side of Mount Erebus and exploded, instantly killing everyone on board. The accident occurred at 12:50 pm at a position of and an elevation of above mean sea level. McMurdo Station attempted to contact the flight after the crash, and informed Air New Zealand headquarters in Auckland that communication with the aircraft had been lost. United States search-and-rescue personnel were placed on standby.