Antarctica New Zealand

Erebus

The Fate of Flight 901

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Polar sun flooded the DC10’s cabin, haloing passengers in ethereal light. One was caught on film as he relaxed in the aisle, glass to lips. Oth­ers cradled cameras or leaned across seats, pressing faces against windows to better see the intricate lattice of sea and ice that stretched away below the aircraft towards the horizon. Air New Zealand cabin crew mingled with the day trippers, recharging glasses, dispensing food. Con­versation crackled. Jokes found easy laughter. More an airborne party than a commercial flight, TE901 had none of the sober formality and numbing routine of scheduled travel. For crew and paying. guests alike, it was special. Out of the ordinary.

What a lark to be cruising in shirt sleeves more than a mile above the frozen wastes, and about to glimpse the dazzling landscape through which Scott and Shackleton once trod as they courted fame and danger.

The jet, which had been gradually shedding height, rounded out of a leisurely turn and levelled, bringing the starboard windows into play once more. Sensing the time was right, John Mulgrew excused himself and made his way forward to the flight deck. A climbing buddy of Ed Hillary, Mulgrew had lost his legs to pulmonary throm­bosis and frostbite in the Himalayas, and now got about on prosthetics. He was also a distinguished Antarctican in his own right, having accompanied Hillary on that wild overland dash to the South Pole in ’58. Afterwards, chaffing at business life and unable to settle, he had taken a gaff-rigged 40-footer around Cape Horn and was nurs­ing dreams of an attempt on the Northwest Passage. Now he found himself a willing commentator on these tourist flights to the ice and the time had come to earn his keep.

Mt Erebus, the world's southernmost active volcano, casts its long shadow over Ross Island and McMurdo Sound.
Mt Erebus, the world’s southernmost active volcano, casts its long shadow over Ross Island and McMurdo Sound.

Captain Jim Collins eased the aircraft into a final roll to starboard as Mulgrew entered, bringing it onto a southerly heading once more. Steadying himself against the aircraft’s 25-degree tilt with practised ease, Mulgrew acknowledged the rest of the flight crew and installed himself in the jump-seat behind the pilot. Ahead, the wide expanse of McMurdo Sound unfolded into clear, white distance under the overcast. They had some 54 km to run until the Dailey Islands turn-point.

It was 0043:20 GMT. Mulgrew scanned the landscape to left and right, ea­ger to interpret the continent for the benefit of those on board. To the right, he could make out the Taylor Valley, one of the glacier channels that bisect the long arc of the Transantarctic Mountains. Out the opposite window lay what he took to be the edge of Ross Island. Yes, there was Cape Bird. Mulgrew pointed out the features on the map that lay across Collins’ knee. They were still on the pro­grammed flight path that took them down the centre of the 70 km-wide sound.

At the invitation of McMurdo Station Air Traffic Control, Collins flew the DC10 visually at an altitude of 1500 feet. This enabled him to best position the aircraft for sightseeing, as pilots on previous flights had done, though for some reason neither Scott Base nor sprawling McMurdo Station at the tip of Hut Point Peninsula was yet visible. Nor could anyone on the flight deck discern Mount Discovery, which must lie directly ahead, beyond the Dailey Islands waypoint. First officer Greg Cassin reported that he was now unable to raise Mac Tower. Moreover, with TE901 now just 41 km out, Mulgrew’s points of reference—the headlands to left and right—were fast disappearing behind the aircraft, leaving nothing but an unsettling, featureless plain ahead. Even the etched line of the horizon seemed to have melted away.

It was now 0049:30.

Perhaps there was a fault in the aircraft’s DME—its distance-measuring equipment. Attempts to contact TACAN—McMurdo’s military navigation aid—to con­firm the distance to run had been unsuccessful.

Despite the clear visibility, Collins decided to follow his customary prudence.

“We’ll have to climb out of this,” he announced. Cas­sin confirmed that they were clear to turn right. “No high ground if you do a one-eighty.”

The calm deliberation was suddenly shattered by the ground-proximity warning signal (GPWS): “Woop… whoop… pull up… whoop… whoop.”

“Five hundred feet,” said flight engineer Gordon Brooks, reading off the altitude.

GPWS: “Pull up…”

Brooks: “Four hundred feet.”

GPWS: “Whoop… whoop… pull up… whoop… whoop… pull up…”

Collins: “Go-round power, please.”

GPWS: “Whoop… whoop…pull…”

(End of recording.)

[Chapter Break]

The morning of Wednesday, November 28, 1979 had carried the warmth of early summer. Out­side Auckland Airport’s international terminal a light breeze greeted the last of the passengers arriving to board the bright-liveried DC10, tethered by an air bridge at the departure gate. The excitement was palpable just 27 days until Christmas, 32 days to see out the 1970s and, most importantly, less than an hour before boarding the last

Antarctic flight of the decade. Though bound for a dis­tant continent of ice and rock at the bottom of the world, TE901 was classed as a domestic flight. There would be no freight, no duty-free purchases and just one piece of hand luggage per passenger. Tickets bore the destination: Auckland-Auckland.

Many of the 237 passengers were middle-aged or eld­erly. There were 23 Americans, a sizable contingent of Japanese tourists, a handful of British, two Canadians, an Australian and one each from Switzerland and France. The rest were New Zealanders. Some, such as 26-year-old police constable Trevor Maskelyne of New Plymouth, had won their seat. Others had been given tickets as a treat. Phillipa Broad had been gifted one for her 21st birthday. Mark Gallagher had been given one by his grandparents, Elsie and Alfred Gallagher. All three were on board. Christchurch teacher Christine Nicholson was heading south to cap off an intensive study course on the Antarc­tic. The head of the New Zealand Tourist Department, Michael Roberts, was there, as was Lady Helen Robb, widow of the eminent heart surgeon Sir Douglas Robb. One couple had secured tickets less than half an hour be­fore take-off.

Wheelchair-bound Aucklander Valgria Rawlins had a last-minute change of heart, but the 76-year-old had been coaxed on board. Hostess Suzanne Marinovic, one of 15 cabin crew rostered for the flight, had overslept and might have missed it, had she not received a phone call from Air New Zealand to rouse her. Another crew mem­ber, steward Stephen Simmons, felt unwell on waking, but showed up regardless.

And so it went. Men and women from diverse back­grounds, many with tender farewell kisses on their cheeks and all about to share the adventure of a lifetime.

Air New Zealand and its trans-Tasman rival Qantas had pioneered commercial flights to the ice within days of each other, in early 1977. By the end of 1979, the New Zealand company had taken more than 2000 sightseers south and the Australians even more—some 7000 passen­gers on 25 charters, mostly using larger Boeing 747s. Qan­tas concentrated on the northern edge of the continent, from George V Land to Victoria Land, with turn-points laid down variously at Dumont D’Urville, Cape Hudson and Cape Hallett.

An earlier plan by Air New Zealand to offer scenic flights to the frozen continent had foundered on a lack of facilities for stopovers on the ice. The expense of con­structing a suitable terminal and the logistical difficulties of getting aviation fuel and service staff to McMurdo had undermined its economic merit. But the introduction to the fleet of the modern, long-range Series 30 DC10 invit­ed a new possibility that of a non-stop round trip which would obviate the need for ground-based support.

An Air New Zealand brochure celebrates the triumph of technology in bringing "isolated, uncompromising" Antarctica within reach of ordinary day-trippers. But the airline, a pioneer of polar tourism, underestimated the continent's danger.
An Air New Zealand brochure celebrates the triumph of technology in bringing “isolated, uncompromising” Antarctica within reach of ordinary day-trippers. But the airline, a pioneer of polar tourism, underestimated the continent’s danger.

An 11-hour proving flight using one of the new aircraft, on February 15, 1977, had gone well: having spent 45 min­utes over McMurdo Sound, the jet’s only communication glitch was an inability to contact Campbell Island. “Flight crew conservative and conscientious in the conduct of this flight,” noted the Civil Aviation inspector on board. “Nil adverse comments. A well conducted flight in all respects.”

A further inspection of the airline’s polar flights, planned for 1979, had never eventuated and Civil Avia­tion’s recommendation that Air New Zealand supply suitable protective clothing to passengers and crew was not implemented either. Whereas Qantas flights were equipped with polar survival gear, Air New Zealand flights carried the usual life rafts, flotation cushions and lifejackets.

In October 1979, in response to the Civil Aviation De­partment’s concerns about the consequences of a crash in such a remote, hostile wilderness and the lack of portable survival radio equipment (as stipulated by the International Civil Aviation Organisation), Air New Zealand stated: “It is our opinion that the carriage of survival suits is unwar­ranted as they would only be used in the event of a land­ing at McMurdo Airfield.” The airline concluded that “on the basis of infrequent exposure to an extremely unlikely emergency situation”, it would not carry survival equip­ment on the four scenic flights scheduled for November.

Nonetheless, the chief purser, Roy McPherson, had in his pocket some cold weather survival notes, handed to him at the pre-flight briefing by a Civil Aviation inspec­tor, which he hoped cabin crew might glance over during the flight.

These days, such nonchalance would be astonishing. Mandatory clothing worn by today’s southbound passen­gers who step through Christchurch’s Antarctic Passenger Terminal include thermal underwear, ski suits, thermal gloves, windproof mitts, survival jackets, cold climate boots… the list is long. The same kit must be worn while flying in fixed-wing aircraft or helicopters in Antarctica. Additionally, on such flights passengers must carry sur­vival bags containing tents, food, additional clothing and medical supplies.

Equally surprising was the airline’s decision to pro­gramme flights over Mount Erebus. After all, no American military aircraft was permitted to do so.

At 3795 m, Erebus is higher than Japan’s Mount Fuji. It is also an active volca­no one of only three in the world with a lava lake.

A pen­nant of steam and particulates hangs constantly about its cone, teased out to the east by the prevailing airstream.

Erebus has long been an inspiring sight. Captain James Clark Ross was the first to see it, in 1841, and named it and nearby Mount Terror after his expedition ships. Hav­ing pushed through pack ice to venture further south than any previous explorer, he beheld it as a thing of awesome power a peak rising up from what he called High Island, clothed in ice and snow and “emitting flame and smoke in great profusion”. Ross had witnessed what was very likely the largest eruption of Erebus ever recorded.

Air New Zealand now offered armchair tourists the chance to get much closer than Ross had to the volcano’s steaming cone. The company’s seductive brochure, The Antarctic Experience, showed the “sentinel of McMurdo” from the flight deck of a DC10 (coincidentally, Peter Mul­grew’s brother Allan, a commercial pilot, occupies the co­pilot’s seat in the photograph). On the same spread, passen­gers Air New Zealand’s “high-flying visitors”— smile as they gaze out, presumably at the same inspiring sight.

The prospect of seeing fire and ice writ large on the landscape helped turn Antarctica into what marketers trumpeted as “the ultimate day trip”.

With all of its excursionists aboard, TE910 lifted off into clear skies at 8.17 AM, and after a “champagne” breakfast (with a cheap and over-sweet New Zealand wine), the aircraft had swept over the offshore Maui oil rig and on across the picturesque Southern Alps before enter­ing the rolling vastness of the Southern Ocean.

On nearing the Auckland Islands, Mulgrew introduced Amundsen: Explorer, the first of three Antarctic-themed films calculated to set the stage for what would be the main act the seventh continent itself. On the return leg to Christchurch, exhausted passengers could unwind with Buck Rogers and the Space Patrol.

Preparations for lunch then got under way in the air­craft’s three galleys. The menu included prawns, scallops, tournedos rossini and chicken souvaroff. For dessert, there was “Peach Erebus”, a playful concoction of peach capped with meringue and cream.

Alan Stokes, the freelance commercial artist who had designed the menu’s cover and the lavish brochure, was himself on board TE901, his complimentary ticket a reward from the airline for his exemplary work. Stokes had also designed the commemorative certificate handed out to passengers, which drew attention to a little-known significance of this flight that it celebrated not only the fourth series of Air New Zealand flights to the Antarctic but half a century of Antarctic aviation.

Exactly 50 years earlier, on November 28, 1929, Richard Evelyn Byrd and three companions had taken off from their Little America base on the Ross Ice Shelf for the South Pole in a Ford trimotor. They reached the pole the next day after a hair-raising flight and their feat—which resulted in Commander Byrd being promoted to rear admiral—marked a turning point in the use of aircraft in Antarctic exploration.

Now, half a century later and just 40 minutes behind TE901, and flying the same course, was a US Military Air Command Lockheed C-141 Starlifter. On board the massive turbofan freighter was an unusual connection with Byrd’s historic flight in the form of Senator Harry F. Byrd, the aviator’s nephew. As a 14-year-old, Harry Byrd had spoken by telephone to the polar explorer on his return to Little America. Now on the anniversary of the flight, the senator was himself heading south with the intention of retracing the epic 1929 journey in a ski-equipped Hercules. Accompanying him was Byrd’s grandson, Robert Byrd Breyer, and two members of the original ground party.

Early sightseeing flights passed close to Erebus, north of Scott Base. Pictured at the controls is Allan Mulgrew, was to lose his life on the volcano's icy slopes.
Early sightseeing flights passed close to Erebus, north of Scott Base. Pictured at the controls is Allan Mulgrew, was to lose his life on the volcano’s icy slopes.

The Air New Zealand DC10 breached the Antarctic Circle, overflying the bleak, uninhabited Balleny Islands at 33,000 feet, just as lunch was being cleared away. Short­ly afterwards, it reached the shattered ice fringe of the Ross Sea off Cape Hallett. Though none could know it, no one aboard TE901 would ever be this far north again.

The forecast from McMurdo was for cloud down to 4000 feet, with visibility at 65 km and occasional snow showers. Collins decided to request a radar letdown on reaching the entrance to McMurdo Sound, which would bring the aircraft out into clear air beneath the cloud base. If, having done that, he and his flight crew found that visi­bility was unacceptable for sightseeing, they would abandon the attempt and turn for the sunlit ranges of Victoria Land.

As it happened, with 100 km to run, sizable areas of clear air opened up beneath them, revealing large ex­panses of sea ice through disintegrating cloud. No longer needing radar assistance, TE901 was cleared by Mac Centre to descend under visual flight rules (or VMC­ visual meteorological conditions—in which flying by sight rather than instruments is permissible) to 1500 feet and then to fly visually beneath the overcast to McMurdo. Collins took the jet through two controlled descending orbits, first a short one to starboard, then a much longer one to port. As he completed the final 180-degree turn that would position the aircraft once more at the head of McMurdo Sound, Peter Mulgrew stepped forward onto the flight deck…

Nearing McMurdo himself, the captain of the C-141 Starlifter, Major Bruce Gumble, heard Collins tell Mc­Murdo Station that he was making a visual descent. Gum­ble had periodically talked to the Air New Zealand crew over the Southern Ocean and now he tried contacting them again to determine their flight path. He received no reply. Nor could he raise them 20 minutes later when he began his own descent.

Senator Byrd stepped off the Starlifter at McMurdo to find himself in the midst of an alert. In Antarctica to celebrate the triumph of flight, he had arrived, it seemed, in the wake of the continent’s worst imaginable air disas­ter. A commercial aircraft with 257 ill-equipped civilians on board had gone missing in one of the world’s harshest and most inaccessible environments. A search was already under way and it was unlikely that any aircraft could be spared for the senator’s commemorative flight due to take place the next day Thanksgiving Day.

[Chapter Break]

At the exclusive Heretaunga golf course, north of Wellington, the first day of the Air New Zealand/Shell Open was drawing to a close. As he left the course, the airline’s chief executive, Morrie Davis, who had been swinging irons with tournament heavy­weights in the pro-am section, was handed news that every airline boss dreads. As the hours passed, hope that TE901 was still airborne dwindled. By 9 PM, the time that the reserve fuel would have been exhausted, it was clear that the DC10 had gone down, either among the ice and rock of Antarctica or in the bone-chilling ocean. Events played out with aching slowness. A crisis centre was set up at the Beehive. An RNZAF Orion with advanced search capabil­ities was despatched from Auckland. Friends and relatives of the overdue passengers sat dazed in the arrivals lounge, some in tears, as they awaited news. Police took names and addresses.

Having returned to Air New Zealand headquarters, overlooking Auckland’s waterfront, Davis sat at the board­room table, hands clasped, as journalists and photogra­phers filed in.

“I wanted to tell you that wreckage has been sighted in Antarctica,” he said sombrely. “The location indicates Mount Erebus…”

[Chapter Break]

Mountaineers rom Scott Base were the first to land at the crash site, which from the air was little more than a dark smear on the volcano’s lower slopes, overlooked by an outcrop called Fang Ridge. Jumping into snow from the hovering helicopter’s skid wind gusts and the sloping ground prevented a landing they were soon amid hor­rific carnage. Bloodied and charred bodies, body parts and wreckage lay strewn about, already dusted by snow flurries. Some of the bodies were naked, their light, summer clothes stripped from them by the force of the impact. Panels of aluminium lifted and tumbled in the wind. The air was heavy with the smell of kerosene. Cameras, handbags, cushions, necklaces, bank notes a thousand tokens of everyday life savagely cut short studded the snow, some barely recognisable, others eerily unscathed despite the violence of the end. One of the search party came across a hand, the bright wedding ring still in place.

It quickly became clear to the advance search party, as they picked their way around the crevassed crash site in buffeting, snow-flecked wind and a sub-zero tempera­ture, that no one had survived the impact. It would be a recovery operation.

Little remained of the DC10 itself, though several large pieces had survived relatively intact, including parts of the undercarriage, a section of fuselage and the severed fin attached to the tail engine, which for several seconds after impact had continued to deliver full power as it tore through the fireball of fuel and exploding metal. The two wing engines had been driven deep into the hard surface by the force of the impact, shearing their turbine blades as the aircraft slammed into the mountainside. The 250­ tonne aircraft, which had been travelling at 475 km/h, punched a four-metre-deep imprint in the ice before ca­reering 600 m up the slope, disintegrating as it went

The mountaineers set up a makeshift camp on the slopes, and within days specialist teams were active be­neath Fang Ridge, guided by flags fluttering from bamboo poles—black to denote the search grids, red for crevasses and green to mark bodies. Members of the newly trained police disaster victim identification unit, photographers, field assistants, surveyors, air accident inspectors and an engineer and chief pilot from Air New Zealand were ac­commodated at Scott Base and airlifted to and from Er­ebus. They worked against the clock; fresh snow was grad­ually burying the debris and it was only a matter of days until summer melt rendered the ice airfield at McMurdo Sound unusable for most planes. Little could be done to discourage the scavenging skuas, which even tore through polythene used to cover bodies before removal, and their presence was a continual torment to the teams on Erebus.

Officials from the aircraft’s manufacturer, McDonnell-Douglas, the engine-maker, General Electric Corpora­tion, and America’s National Transportation Safety Board (NTSB) beat a hasty path to McMurdo from the United States, arriving with impressive speed on December 1.

100_Erebus_05

The plane’s manufacturer, in particular, was secretly worried that mechanical failure had been responsible for the crash. It was not an unreasonable fear. Since enter­ing service with the world’s airlines, DC10s had been involved in several high-profile accidents. In 1972, an eastbound American Airlines DC10 suffered explosive decompression when a cargo door tore out over the Canadian city of Windsor. Miraculously, no one died in that incident, but when the same thing happened to a Turkish Airlines DC10 en route to London two years later, all 346 people on board were killed. The first of Air New Zealand’s DC10s, delivered in 1973, incorporated safety modifications, but the aircraft again made head­lines in May 1979, just months before Erebus, when an American Airlines flight out of Chicago crashed, killing all 273 people on board, after a wing-mounted engine broke free. Uncertainty about what had caused the Air New Zealand crash kept the McDonnell-Douglas people in Antarctica on edge.

Early success for the investigators came with the swift recovery of two vital pieces of equipment: the aircraft’s cockpit voice recorder (CVR), which, it was hoped, con­tained a tape of the final 30 minutes of conversation on the flight deck, and the ‘black box’ digital flight data recorder, designed to preserve detailed information on how the air­craft had been flown since takeoff. The navigation com­puter’s memory modules and even exposed film from the many surviving cameras were also collected to help piece together the final moments of TE901.

Even as the University of Auckland Medical School was being readied to receive the bodies of the crash victims for autopsies by five teams of pathologists, the recorders were undergoing what would prove to be a controversial decod­ing and transcription at the headquarters of the NTSB in Washington, DC.

[sidebar-1]

Under intense pressure from all sides to determine the circumstances of the crash, New Zealand’s Chief Inspec­tor of Air Accidents, Ron Chippindale, had soon reached his conclusion. After sifting all the evidence, consulting aviation experts and studying the contents of the CVR recording, he believed the crew had become uncertain of their position while enveloped in thick cloud in the vicinity of McMurdo Sound. Flying below the minimum authorised altitude while disoriented, they had struck the volcano at full power. It was undoubtedly distressing but to Chippindale, ex-RNZAF squadron leader and seasoned crash investigator, it was clear that the Erebus disaster was caused by pilot error. This was recorded in his interim report and delivered to the Minister of Civil March 4, 1980, although not made public.

It wasn’t enough. The leader of the parliamentary op­position, Bill Rowling, called for a public inquiry, as was common practice in other countries when questions re­mained about a major air accident. This was the world’s fourth-worst air tragedy and New Zealand’s deadliest disaster eclipsing in lives lost even the 1931 Napier earthquake. It had struck ordinary folk aboard one of the most advanced airliners ever made, and it had done so in a distant, inhospitable wilderness of ice mere hours after they had stepped from home soil.

Moreover, and not to put too fine a point on it, the Erebus crash dealt a severe blow to an airline which, es­sentially, was run as a government department and whose sole registered shareholder was the Prime Minister of New Zealand, Robert Muldoon. Another government de­partment was also implicated: Civil Aviation had approved the ice routes and had established the conditions under which they were to be flown. Finally, there was the vexed question of insurance which, if wilful misconduct could be proved, potentially exposed the company’s underwriters to significant claims for damages.

Bowing to pressure, the Government announced on April 21, 1980, the appointment of a High Court Judge, Justice Peter Mahon, as a one-man royal commission of inquiry into the crash. Mahon was given four months to conduct his inquiry (there were to be several extensions), the findings of which, it was widely assumed, would mere­ly endorse those of the chief inspector.

Surprisingly, the commission was pre-empted by the publication of Chippindale’s final report on June 20—an act that ensured it could be produced in evidence. Many clearly believed that the release of the report ended the need for any inquiry. On the day of its publication, avia­tion writer Ken Hickson voiced the thoughts of others when he repeated on air his opinion that the inspector had more than adequately surveyed the ground that would be covered by the royal commission. Moreover, he questioned the competence and the authority of the investigating team.

But this was not to reckon on the singular qualities of Mahon, his independent mind, his instinct for due process and his tenacity what his son Sam has called his “bloody-minded Irish obstinacy”. In April 1981, after 75 sitting days, the examining and cross-examining of 52 witnesses, the study of 284 documentary exhibits and 3083 pages of evidence and personal overseas investiga­tions in Europe, North America and Antarctica, the commissioner came to a surprisingly different conclu­sion, one that shocked the nation.

A US Navy helicopter flies over the wreckage soon after its discovery. The crash point is at the upper left. The force of the impact, which rendered much of the wide-bodied DC10 unrecognisable, opened crevasses on the sloping ground, adding to the dangers for the recovery team.
A US Navy helicopter flies over the wreckage soon after its discovery. The crash point is at the upper left. The force of the impact, which rendered much of the wide-bodied DC10 unrecognisable, opened crevasses on the sloping ground, adding to the dangers for the recovery team.
A memorial cross marks the deaths from Shackleton's Imperial Trans-Antarctic Expedition more than half a century ago. Dozens have lost their lives challenging the white continent's hostile environment, and the disaster of 1979 showed that modern technology is no guarantee of safety. Even the arm-chair adventurers cruising in jet-age comfort aboard TE901 were added to their number.
A memorial cross marks the deaths from Shackleton’s Imperial Trans-Antarctic Expedition more than half a century ago. Dozens have lost their lives challenging the white continent’s hostile environment, and the disaster of 1979 showed that modern technology is no guarantee of safety. Even the arm-chair adventurers cruising in jet-age comfort aboard TE901 were added to their number.

The investigation into what Mahon was to call a “trag­edy unique in the annals of the air” did not require any engineering or aeronautical expertise. The aircraft and its equipment had functioned perfectly until the very moment of impact. The questions to be answered, he said, were almost all inferences from known facts. Why was TE901 on that course? Why at that altitude? And most importantly, why had none of the aircrew seen the moun­tainside in broad daylight?

As the hearing proceeded, Chippindale’s findings—his procedure, even seemed less and less satisfactory to the methodically minded judge. At one point, faced with pas­senger photographs which incontrovertibly showed good visibility from the cabin windows, the inspector modified his interpretation of events to suggest that Captain Collins may not have been in cloud, but rather “flying towards an area of poor surface and horizon definition”. Such semantic wriggling changed little, however. For Chip­pindale, the bottom line still remained pilot error. The aircrew, he noted, had only to consult their onboard radar, which would have depicted the mountainous terrain.

In this, however, he was found to be wrong. Mahon’s inquiries at the radar maker’s factory in Florida revealed the surprising fact that the Bendix radar was tuned to look for cloud. It is moisture in clouds that causes turbulence and the great advantage of such radar is that at night it enables pilots to identify and navigate around these areas of passenger discomfort. Given that Antarctica is drier than the Sahara Desert, Erebus would not have shown up in the radar’s weather mode, and even in mapping mode the rising ground would have been indistinguishable from the pack ice of McMurdo Sound.

There were worse errors. The tape transcript, which fostered an impression—one that lingers to this day­ of disorientation and rising panic among the crew, was shown to be seriously flawed. Flight deck microphones record conversations imperfectly at the best of times. With people moving in and out of range, and when there is a great deal of cross-talk going on, getting a fix on exactly what was said is challenging. Difficulties are com­pounded when the transcriber has a preconception of what occurred. When faced with the transcribed fragment from the last moments of TE901, “a bit thick here, eh Bert?”, no one thought to ask whether there was a Bert on the flight deck. That, and the comment attributed to flight engineer Nick Moloney, “You’re a long while on instruments at this time, are you?” was seized upon by media here and overseas as evidence of an aircraft caught in impenetra­ble cloud. The practised ear of Colonel Paul Turner, an American specialist interviewed by Mahon, heard things differently. The first speaker had, in fact said, “This is Cape Bird”. The second fragment, referring to instru­ments, consisted of two interlocking conversations.

It was from such slender threads that the reputation of TE901’s flight crew hung.

Strewn with bodies and wreckage, the crash site was swept by blizzards which tore at loose metal panels and whipped up powder snow, hampering recovery efforts. Bodies were laboriously retrieved and airlifted out (below) before being taken to Auckland for formal identification. Many were not found, however, and in 1981 the site was declared a tomb. In 1997 it was designated as Antarctic Specially Protected Area.
Strewn with bodies and wreckage, the crash site was swept by blizzards which tore at loose metal panels and whipped up powder snow, hampering recovery efforts. Bodies were laboriously retrieved and airlifted out (below) before being taken to Auckland for formal identification. Many were not found, however, and in 1981 the site was declared a tomb. In 1997 it was designated as Antarctic Specially Protected Area.

100_Erebus_08

Having studied the material exhaustively, Mahon could no longer subscribe to the idea of “mounting alarm” among the crew. Modern aviation, he discovered, employed a technique known as “fail-safe” or “crew-co­operative” training to monitor and coordinate the actions of everyone on the flight deck. Anyone pilot, co-pilot or engineer who drew attention to any matter would be responded to. This was known as the “challenge” procedure and, in part, was designed to detect any incapacity in a member of the crew. TE901’s other flight engineer, Gor­don Brooks, was himself an instructor in the technique. Collins would never have been permitted to fly in the manner suggested by Chippindale.

Mahon began to wonder whether the chief inspector, who had never flown a commercial jet himself and whose investigations to date had focused largely on accidents in­volving small aircraft almost always caused by pilot error, had fully grasped what was before him.

But if Mahon was uneasy about the inspector’s findings, the attitude of certain individuals at Air New Zealand tried him—and the New Zealand Air Line Pilots’ As­sociation also represented at the hearing sorely. It is all in Mahon’s 1984 book, Verdict on Erebus, written after the fallout from his report had died away: the airline’s chief executive ordering the shredding of “surplus” documents relating to the Antarctic flights within days of the disaster; the disappearance of Collins’ notebook, atlas and flight maps, which had been retrieved from the crash site and handed to Air New Zealand before disappearing—only an empty ring binder eventually being returned to the cap­tain’s widow; the parade of airline executives who blandly denied all knowledge of low-level flights in Antarctica despite many articles by travelling journalists, some published by the airline itself, attesting to it as common practice. A whole series of obstructions and evasions were created, said Mahon, “in a bold attempt to thwart the dis­covery of the truth”.

Sam Mahon tells of his father making a rare visit to his Christchurch home one cold autumn evening, after the 167-page report on the Erebus Inquiry had been signed and delivered to the government printers. They had lin­gered together among the willows by a pond, hoping for game. “I remember him lighting a cigarette in the niche of his lapel, the shotgun broken in the crook of his arm, the brief smoke shredding in a wind pouring from an empty sky. ‘Tomorrow,’ he said, ‘all hell’s going to break loose.’”

It did. In his report Justice Mahon had discounted pi­lot error, finding instead that systemic errors within the airline had put TE901 on a collision course with Erebus, even as an extraordinary series of coincidences had con­spired to convince the crew that they were somewhere else entirely.

In a book written five years after Erebus, Peter Mahon revealed how, as Royal Commissioner, he reached his controversial conclusions. The report itself, a painstaking account of the country's worst disaster, was repeatedly delayed as Mahon doggedly went about his investigation.
In a book written five years after Erebus, Peter Mahon revealed how, as Royal Commissioner, he reached his controversial conclusions. The report itself, a painstaking account of the country’s worst disaster, was repeatedly delayed as Mahon doggedly went about his investigation.

The DC10 aircraft operated by Air New Zealand were equipped with highly accurate computerised inertial navigation systems and could be programmed to fly to a destination by inputting the coordinates of a series of way-points along the intended route. The original Antarctic route lay over Lewis Bay and Erebus, and early flights had enjoyed brilliant conditions which had enabled pilots to depart from the navigation track for sightseeing. However, 14 months before the crash, while the airline’s method of storing and creating flight plans was being computerised, an error was introduced. A data entry operator keyed a 4 instead of a 6 into the machine, shifting the route some 50 km to the west, so that it passed down the centre of McMurdo Sound. No one questioned the new flight path because the mistake, ironically, resulted in a safer route. It was this route on which the crew were briefed 19 days before the fatal flight.

In a second twist of fate, the night before before Col­lins took TE901 south, the airline’s flight planners cor­rected what they thought was an insignificant input error, effectively programming the aircraft for its destiny on Erebus. The flight crew remained ignorant of this last alteration and, believing that the navigation track would take them safely down McMurdo Sound, lost what pilots call “situational awareness”.

Mahon’s report was a masterly and groundbreaking reconstruction of events, and if it had been left at that per­haps he would not have incurred the wrath of some of the most powerful people in the land. Mahon wasn’t the sort to stay his hand.

“An orchestrated litany of lies,” he called the airline’s evidence. To Sam Mahon, the phrase was crafted by his father to lodge itself in the nation’s psyche. “It is written in perfect iambic pentameter, the rhythm of Shakespeare… He knew exactly what he was doing.”

What Justice Mahon intended, above all, was to dispel what he saw as the false impressions of reckless flying cre­ated in the public mind by the widely circulated extracts from the chief inspector’s report. It was not enough mere­ly to state that he preferred one set of evidence to another. To give the report any weight, he felt compelled to issue a finding of credibility against the airline witnesses.

The decision was to entail an enormous personal cost. In the pandemonium that followed, Morrie Davis felt compelled to resign, the Prime Minister turned on Mahon and pilots and aviation specialists found themselves in one or other of two entrenched and opposing camps. Air New Zealand applied to have Mahon’s findings overturned by the Court of Appeal. The court, in turn, rapped Mahon for not putting his allegations to airline witnesses at the royal commission hearing. Stunned by the rebuke, Mahon resigned. He then appealed for redress to the Privy Coun­cil which, in a damning decision in October 1983, deter­mined that through his actions he had “failed to observe the rules of natural justice”.

Resentment and humiliation at his shabby treatment, in the face of what even the Privy Council admitted to be “brilliant and painstaking investigative work”, were said to have taken Peter Mahon to an early grave. He died in 1986, aged 62. Even public clamour for a posthumous knighthood was brushed aside by the newly installed La­bour Government.

The impact of the crash itself, meanwhile, continued to reverberate through the decades, its finer points debated still, blame apportioned endlessly by those who hotly defended one or other position. Even today, 30 years on, there are heartfelt acts of remembrance by many whose grief ran deep.

Mahon once claimed that the “ultimate key” to the tragedy of TE901 lay in the white silence of Lewis Bay. He was alluding to the conjuring tricks of polar light. But he might with equal truth have been invoking the men and women who met their end there, on the flanks of a volcano. The curious souls filled with wonder, and those with a job to do. Erebus took them to its heart. Mahon, too, eventually. And all of us, a little.

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