![]() Wreckage of Air New Zealand Flight 901
on the side of Mount Erebus, Antarctica. |
|
Summary | |
---|---|
Date | 28 November 1979 |
Type | Controlled flight into terrain |
Site | Mount Erebus, Ross Island, Antarctica |
Passengers | 237 |
Crew | 20 |
Injuries | 0 |
Fatalities | 257 |
Survivors | 0 |
Aircraft type | McDonnell Douglas DC-10-30 |
Operator | Air New Zealand |
Tail number | ZK-NZP |
Flight origin | Auckland International Airport |
Destination | Christchurch International Airport |
Air New Zealand Flight 901 (TE901) was a scheduled Antarctic sightseeing flight from Auckland International Airport in New Zealand. The Antarctic sightseeing flights were operated with McDonnell Douglas DC-10-30 aircraft and began in February 1977. On 28 November 1979 the 14th flight crashed into Mount Erebus, killing all 237 passengers and 20 crewmembers aboard.
Contents |
The flight was designed and marketed as a unique sightseeing experience, carrying an experienced Antarctic guide who pointed out scenic features and landmarks using the aircraft public-address system. Passengers enjoyed a low-flying sweep of McMurdo Sound, returning to New Zealand the same day.[1]
Dignitaries such as Sir Edmund Hillary had acted as guides on previous flights. Sir Edmund was scheduled to act as the guide for the fatal flight, but had to cancel due to other commitments. His long-time friend and climbing companion, Peter Mulgrew, stood in as guide.
The flights usually operated at about 85% of capacity; the empty seats, usually the centre ones, allowed passengers to move more easily about the cabin to look out of the windows.
The aircraft that day was a DC-10-30, registered ZK-NZP, which had been delivered to Air New Zealand in December 1974. The plane itself had an unblemished flying record, and was utilized by Air New Zealand for its long-haul routes.
Captain Jim Collins and co-pilot Greg Cassin had never flown to Antarctica before, but they were experienced pilots and the flight was considered a simple one. On 9 November 1979, 19 days before departure, the two pilots had attended a briefing in which they were given a copy of the previous flight's flight plan. [1]
However, unbeknownst to Captain Collins, at the time of the briefing, the flight plan coordinates transcribed into Air New Zealand's ground computer differed from the route flight plan approved in 1977 by New Zealand's Department of Transport's Civil Aviation Division. The approved flight plan was along a track directly from Cape Hallett to the McMurdo Non-Directional Beacon (NDB), which, coincidentally, entailed flying almost directly over the 12,448 ft peak of Mt Erebus. However, the print out from Air New Zealand's ground computer system presented at the November 9 briefing corresponded to a southerly flight path down the middle of the wide McMurdo Sound, leaving Mt Erebus approximately 27 miles to the east. The majority of previous flights had also entered this flight plan's coordinates into their aircraft INS navigational systems and flown the McMurdo Sound route, unaware that the route flown did not correspond with the approved route.
Eventually, the Captain of a previous flight on November 14 compared the coordinates of the McMurdo TACAN navigation beacon (approximately 3 miles east of McMurdo NDB), and the McMurdo waypoint that the flight crew had entered into the INS, and was surprised to find a large distance between the two. After this flight, this Captain 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 subsequently resolve 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 Navigation section changed the McMurdo waypoint coordinate stored in the ground computer system at approximately 1:40 am on the morning of the flight. Crucially, however, the flight crew of Flight 901 was not notified of the change. The flight plan print-out given to the crew on the morning of the flight, which was subsequently hand entered by the flight crew into the aircraft's INS, differed from the flight plan presented at the November 9 briefing and to Captain Collins' map mark-ups he had prepared the night previously. The key difference between the routes was that the flight plan presented at the November 9 briefing corresponded to a track down McMurdo Sound, giving Mt 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 Mt Erebus. In contrast to the McMurdo Sound route, the updated route would result in a collision with Mt Erebus if this leg was flown at an altitude of less than 13,000 ft.
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 (later estimated to be at approximately 2,000-3,000 feet) whilst over water in order to establish visible contact with surface landmarks, and afford the passengers a better view. It was established that either the flight crew was unaware, or ignored, the approved route's Minimum Safe Altitude (MSA) of 16,000 ft for the approach to Mt Erebus, and 6,000 ft in the sector south of Mt Erebus (and then only when the cloud base was at 7,000 ft or better). However, photos and news stories from previous flights showed that many of these had also been flown at levels substantially below the route's MSA. In addition, pre-flight briefings for previous flights had authorised descents to any altitude authorised by the US Air Traffic Controller 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 ATC advised Flight 901 that it was authorised to descend to 1,500 ft.
Cockpit Voice Recorder (CVR) transcripts from the last minutes of the flight prior to impact with Mt Erebus indicated that the flight crew believed they were flying over McMurdo Sound with the Ross Ice Shelf visible on the horizon, well to the west of Mt Erebus, when in reality they were flying directly towards 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. Approximately 6 minutes after completing a descent in Visual Meteorological Conditions, in good weather and with visibility out to at least 23 miles, Flight 901 collided with Mt Erebus at an altitude of approximately 1,500 ft.
Collins and Cassin input the coordinates into the plane's computer before they departed at 8.21 a.m. NZDT (1921 GMT, November 27) from Auckland International Airport. The flight was supposed to arrive back in Auckland at 6.09 p.m.[2] Unknown to them, the coordinates had been modified earlier that morning to correct the error introduced years previously and undetected until now. These new coordinates changed the flight plan to fly 45 kilometres (28 miles) east of where the pilots intended the plane to fly. The coordinates instructed the plane to fly over Lewis Bay and directly over Mount Erebus, a 3,794 m (12,448 ft) high volcano, instead of over McMurdo Sound.[1]
About four hours after a smooth take-off the flight was 70 kilometres (42 miles) away from McMurdo Station. The radio communications centre there allowed the pilots to descend to 10,000 ft (3,050 m) and to continue "visually." Air safety regulations at the time did not allow flights to descend to lower than 6,000 ft (1,830 m), even in good weather, although Air New Zealand's own travel magazine showed photographs of previous flights clearly operating below 6,000 ft (1,800 m). Collins believed the plane was over open water.[1]
Collins told McMurdo Station that he would be dropping to 2,000 ft (610 m), at which point he switched control of the aircraft to the automated computer system. At the time there was a layer of cloud that blended with the white of the volcano, forming a sector whiteout - there was no contrast between the two to warn the pilots. The effect was to fool all on the flight deck into thinking 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. As it was little understood, even by 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 in actual fact they were flying over Lewis Bay in front of Mt. Erebus.
At 12.49 p.m., the Ground Proximity Warning System began sounding a warning that the plane was dangerously close to terrain. Although Collins immediately requested go-around power, [3] there was no time to divert the aircraft and six seconds later the plane collided with the side of Mount Erebus and disintegrated, instantly killing all on board. The pilot did not pull vigorously on the control column as a reflex to seeing imminent death, instead he raised the nose of the aircraft 15° as rehearsed in training - it would then seem likely they never recognised their perfect white view as a mountain. Most of the aircraft was smashed into small pieces, with the exception of the empennage. The wreckage burned vigorously in a pool of jet fuel, with much material sinking into the melted ice, which later re-froze.
McMurdo Station attempted to contact the flight after the crash, and informed Air New Zealand headquarters in Auckland that communication with the plane had been lost. United States search and rescue personnel were placed on standby.[1]
At 1:00 p.m. the United States Navy released a situation report, stating:
Data gathered at 3:43 p.m. was added to the situation report, stating that the visibility was 40 miles (64 km). It also stated that six aircraft had been launched to find the flight.[5]
At 10:00 p.m., about half an hour after the plane would have run out of fuel, Air New Zealand informed the press that it believed the aircraft to be lost. Rescue teams searched along the assumed flight path, but found nothing. At 12:55 a.m. the crew of a United States Navy plane discovered unidentified debris along the side of Mount Erebus.[6] No survivors could be seen. Twenty hours after the crash, helicopters with search parties managed to land on the side of the mountain. It was confirmed that the wreckage was that of flight 901 and that all 237 passengers and 20 crewmembers had been killed. The aircraft's altitude at the time of the collision was 1,465 ft (445 m).
Efforts for recovery were extensive, owing in part to the pressure from Japan, as 24 passengers had been Japanese. The operation lasted until 9 December 1979, with up to 60 recovery workers on site at a time. The vertical stabilizer section of the plane, with the koru intact, was seen in the snow [1]. Bodies and fragments of the aircraft were flown back to Auckland.[7] The remains of 44 of the victims were not individually identified, and the funeral for them was held on 22 February 1980.
[1] The nationalities of the passengers and crew included:
A team of New Zealand Police officers and a Mountain Face Rescue team were dispatched on a No 40 Squadron C-130 Hercules aircraft.
The job of individual identification took many weeks and was largely done by teams of pathologists, dentists and police. The mortuary team was led by Inspector Jim Morgan, who collated and edited a report on the recovery operation. Record keeping had to be meticulous because of the number and fragmented state of the human remains that had to be identified to the satisfaction of the coroner. From a purely technical point of view the exercise was both innovative and highly successful, with 83% of the deceased eventually being identified, sometimes from evidence such as a finger capable of yielding a print, or keys in a pocket.
The fact that we all spent about a week camped in polar tents amid the wreckage and dead bodies, maintaining a 24 hour work schedule says it all. We split the men into two shifts (12 hours on and 12 off), and recovered with great effort all the human remains at the site. Many bodies were trapped under tons of fuselage and wings and much physical effort was required to dig them out and extract them.
Initially, there was very little water at the site and we had only one bowl between all of us to wash our hands in before eating. The water was black. In the first days on site we did not wash plates and utensils after eating but handed them on to the next shift because we were unable to wash them. I could not eat my first meal on site because it was a meat stew. Our polar clothing became covered in black human grease (a result of burns on the bodies).
We felt relieved when the first resupply of woollen gloves arrived because ours had become saturated in human grease, however, we needed the finger movement that wool gloves afforded, i.e. writing down the details of what we saw and assigning body and grid numbers to all body parts and labeling them. All bodies and body parts were photographed in situ by U.S. Navy photographers who worked with us. Also, U.S. Navy personnel helped us to lift and pack bodies into body bags which was very exhausting work.
Later, the Skua gulls were eating the bodies in front of us, causing us much mental anguish as well as destroying the chances of identifying the corpses. We tried to shoo them away but to no avail, we then threw flares, also to no avail. Because of this we had to pick up all the bodies/parts that had been bagged and create 11 large piles of human remains around the crash site in order to bury them under snow to keep the birds off. To do this we had to scoop up the top layer of snow over the crash site and bury them, only later to uncover them when the weather cleared and the helos were able to get back on the site. It was immensely exhausting work.
After we had almost completed the mission, we were trapped by bad weather and isolated. At that point, NZPO2 and I allowed the liquor that had survived the crash to be given out and we had a party (macabre, but we had to let off steam).
We ran out of cigarettes, a catastrophe that caused all persons, civilians and Police on site, to hand in their personal supplies so we could dish them out equally and spin out the supply we had. As the weather cleared, the helos were able to get back and we then were able to hook the piles of bodies in cargo nets under the helicopters and they were taken to McMurdo. This was doubly exhausting because we also had to wind down the personnel numbers with each helo load and that left the remaining people with more work to do. It was exhausting uncovering the bodies and loading them and dangerous too as debris from the crash site was whipped up by the helo rotors. Risks were taken by all those involved in this work. The civilians from McDonnell Douglas, MOT and US Navy personnel were first to leave and then the Police and DSIR followed. I am proud of my service and those of my colleagues on Mount Erebus.[8]
—Jim Morgan
The last searchers off the mountain were Sergeant Mark Penn and Constable Al Windleburn and several DSIR personnel, after a final 36 hours non-stop shift. When this group got back to "Mac Town" McMurdo Station, they were met by the U.S. Navy Fire Crew who told them to strip naked and jump into the (heated) firehouse water tank.
In 1979 the post traumatic stress suffered by the body recovery and identification teams was recognised, some of whom broke down under their grim duty. Counselling was offered to all who wished it, and the debriefing report specifically noted the need for officers in command of such operations to know how to recognise and deal with the signs of stress in staff. It took several years more for psychological support to become standard practice in the New Zealand Police.
There was no official group recognition for the efforts of the police involved on this occasion, but Inspector R. S. Mitchell, leader of the body recovery team, and Inspector Morgan, leader of the DVI team, were awarded the OBE for their services in relation to this disaster.
In 2006 the New Zealand Special Service Medal (Erebus) was instituted to recognise the service of New Zealanders, and citizens of the United States of America and other countries, who were involved in the body recovery, identification and crash investigation phases of Operation Overdue.
The accident report compiled by New Zealand's chief inspector of air accidents, Ron Chippindale, was released on 12 June 1980. It cited pilot error as the principal cause of the accident and attributed blame to the decision of Collins to descend below the customary minimum altitude level, and continue at that height when the crew was unsure of the plane's position. The customary minimum altitude prohibited descent below 6,000 ft (1,830 m) even under good weather conditions, but a combination of factors led the captain to believe the plane was over the sea (the middle of McMurdo Sound and few small low islands), and previous flight 901 pilots had regularly flown low over the area to give passengers a better view, as evidenced by photographs in Air New Zealand's own travel magazine and by first-hand accounts of personnel based on the ground at NZ's Scott Base.
In response to public demand, the New Zealand Government announced a further one-man Royal Commission of Inquiry into the accident, to be performed by the highly respected judge Justice Peter Mahon.
Mahon's report, released on 27 April 1981, cleared the crew of blame for the disaster. Mahon said the single, dominant and effective cause of the crash was Air New Zealand's alteration of the flight plan waypoint coordinates in the ground navigation computer without advising the crew. The new flight plan took the aircraft directly at the mountain, rather than along its flank. Due to whiteout conditions, "a malevolent trick of the polar light", the crew were unable to visually identify the mountain in front of them. Furthermore, they may have experienced a rare meteorological phenomenon called sector whiteout which creates the visual illusion of a flat horizon far in the distance (it appeared to be a very broad gap between cloud layers allowing a view of the distant Ross Ice Shelf and beyond). Mahon noted that the flight crew, with many thousands of hours of flight time between them, had considerable experience with the extreme accuracy of the aircraft's inertial navigation system. Mahon also found that the radio communications centre at McMurdo Station had authorised Collins to descend to 1,500 ft (450 m), below the minimum safe level.
In para. 377 of his report, Mahon controversially claimed airline executives and senior (management) pilots engaged in a conspiracy to whitewash the inquiry, famously accusing them of "an orchestrated litany of lies" by covering up evidence and lying to investigators. Mahon found that in the original report Chippindale had a poor grasp of the flying involved in jet airline operation, as he (and the New Zealand CAA in general) was typically involved in investigating simple light aircraft crashes. Chippindale's investigation techniques were revealed as lacking in rigour, allowing for errors and avoidable gaps in knowledge to occur in reports. Consequently Chippindale entirely missed the importance of the flight plan change and the rare meteorological conditions of Antarctica. Had the pilots been informed of the flight plan change, the crash would have been avoided.
Air New Zealand appealed against Mahon's findings to the Court of Appeal, which set aside the costs order against the airline. Mahon in turn appealed to the Privy Council in London. His findings as to the cause of the accident, namely reprogramming of the aircraft's flight plan by the ground crew who then failed to inform the flight crew, had not been challenged before the Court of Appeal, and so were not challenged before the Privy Council. His conclusion that the crash was the result of the aircrew being misdirected as to their flight path, not due to pilot error, therefore remained. But the Board held that Mahon had acted in excess of his jurisdiction and in breach of natural justice by going on to make findings of a conspiracy by Air New Zealand to cover up the errors of the ground staff. In their judgment, delivered on 20 October 1982, the Law Lords dismissed Mahon's appeal and upheld the decision of the Court of Appeal. Aviation researcher John King wrote in his book New Zealand Tragedies, Aviation:
"Exhibit 164" was a photocopied diagram of McMurdo Sound showing a southbound flight path passing west of Ross Island and a northbound path passing the island on the east. The diagram did not extend sufficiently far south to show where, how, or even if they joined, and left the two paths disconnected. Evidence had been given to the effect that the diagram had been included in the flight crew's briefing documentation.
Justice Mahon's report was finally tabled in Parliament by the then Minister of Transport, Maurice Williamson, in 1999.
The crash of flight 901 remains one of New Zealand's two deadliest disasters, along with the Napier earthquake. A wooden cross was erected above Scott Base to commemorate the accident. It was replaced in 1986 with an aluminium cross after the original was eroded by low temperatures, wind and moisture.
Almost all of the aircraft's wreckage still lies where it came to rest on the slopes of Mount Erebus, under a layer of snow and ice. During warm periods, when snow recedes, it is still visible from the air.
A television miniseries, Erebus: The Aftermath, focusing on the investigation and the Royal Commission of Inquiry, was broadcast in New Zealand and Australia in 1988.
The phrase "an orchestrated litany of lies" has entered New Zealand popular culture.[9][10][11]
In the New Zealand Queen's Birthday Honours list in June 2007 Captain Gordon Vette was awarded the ONZM (Officer of the New Zealand Order of Merit), recognising his services in assisting Justice Mahon during the Erebus Inquiry. Vette's book, Impact Erebus, provides a commentary of the flight, its crash and the subsequent investigations.
In 2008, Justice Mahon was posthumously awarded the Jim Collins Memorial Award by the New Zealand Airline Pilots Association for exceptional contributions to air safety, "in forever changing the general approach used in transport accidents investigations world wide." [12]
The registration of the crashed aircraft, ZK-NZP, has not been reissued.
Bibliography: