A mystery resolved: Last flight of doomed Airbus

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PARIS - It was a cloudy November evening, a little brisk but not too cold to deter the strollers at Canet-Plage, adding a touch of life to a small beach resort during the off season.

These families and teenagers would witness an event that would be etched on their retinas: the final agony of an Air New Zealand jet.

"I was on patrol at the time," recalled Frederic Franses, a gendarme.
"I saw a plane flying along at a height of about two or three hundred metres. All of a sudden we saw it nosedive. It was clear something was wrong, there was a problem. The pilot tried to bring the nose up, the plane pitched upwards and then it smashed headlong into the sea."

A giant white plume of water reached skywards, followed a few seconds later by a boom, which some witnesses described as a growl, as the sound rolled across seven kilometres of Mediterranean.

Seven men lost their lives when the Airbus twinjet crashed on November 27 2008 during what should have been an ordinary test flight.

They were two German pilots, whose charter company, XL Airways Germany, was handing the plane back after a two-year lease; a pilot and three engineers working for Air New Zealand; and an inspector from New Zealand's Civil Aviation Authority.

The disaster triggered shockwaves in the aviation industry. The A320 was little more than three years old, had notched up just 7,000 hours of flying time and had been maintained to the highest standards.

Its bizarre contortions in those final moments raised an alarming question. Had some flaw emerged in the "fly-by-wire" flight system of one of the world's most admired aircraft, a plane sold in the thousands?

The accident also plunged Air New Zealand into a corporate nightmare. The cherished national symbol, an airline whose reputation ranked among the world's finest, was badly shaken. TV footage showed the wretched sight of the plane's tailfin, emblazoned with the koru, being fished from the grey seas. Memories revived of the 1979 Mount Erebus catastrophe.

Over 22 months, a French-led multinational team working in nine areas of expertise strove to explain the mystery. They have provided an answer that has many implications for an industry that is as fast-growing as it is hard-pressed.

"Looking at this crash and what caused it, you have to say that there are operational issues all around," said an investigator who was intimately involved in the probe and spoke on condition of anonymity.
Figuring out the causes of an air crash is like resolving a jigsaw puzzle in 3-D.

Sleuths take their evidence from a variety of sources - witness accounts, maintenance records, data from air traffic control and radar, pieces from the crash site and, most crucially, the "black boxes," the two recorders that register the plane's final movements and the conversation on the flight deck.

But this investigation almost foundered from the start. Hitting the sea at an angle of 14 degrees and almost 500 kph, the plane had shattered into a trail of wreckage that sank into thick sand at a depth of 35 metres. Visibility was very poor, with sand churned up by powerful autumnal currents.

It took a taskforce of 140 troops, gendarmes and divers, backed by helicopters, a minesweeper and a submersible robot, to retrieve the recorders. It would be two months before the final human remains, badly mangled, were recovered.

The crash was so severe that the black boxes were badly damaged, defeating the efforts of French engineers to retrieve their data. In a last throw of the dice, the recorders were sent to their US maker, Honeywell, which teased out the precious testimony.
Separately, the accident probe followed another path: what had happened in the run-up to the fateful flight?

On November 3 2008, XL Airways had ferried the plane to Perpignan for maintenance work and repainting, as stipulated in the handback terms in the lease contract. The job was carried out by a French company, EAS Industries.

With this work completed, XL Airways and Air New Zealand agreed on a flight to certify the plane's airworthiness. It was scheduled for November 27, and planned to last two hours, 35 minutes over western France with a return to Perpignan. After the flight, the plane was supposed to head to Frankfurt.

Beneath its spartan prose, the report by France's Bureau d'Enquetes et d'Analyses (BEA) investigation board is a compelling tale of a doomed mission.

Misjudgment, inadequate training and preparation and slipshod maintenance combined to send the A320 into a stall from which the plane could never recover, it says.

The report, published in Paris on Thursday (Friday NZ time), points the finger in particular at the decision of those onboard to carry out a slow-speed maneuver at a height of just 3,000 feet (925 metres). The altitude was so low that when the pilots lost control, the plane had no chance of recovery.

It also condemned the test flight as "improvised" and marked by time pressure, for takeoff had been delayed by two hours.

Fuzzy communications, poor coordination and tension prevailed on the flight deck. The two German personnel at the controls had had no training in test flights, while the Air New Zealand pilot behind them was busy running through his checklist, failing to respond to a sharp fall in the speed indicators that heralded an impending stall.

"The crew should have been prepared for things to go wrong," said one of the inquiry team. "A pilot cannot assume the plane will demonstrate [perform] safely. On a test flight, you should be prepared."

A more harrowing factor was this: three days before the handover, cleaning crews had rinsed off the aircraft. Investigators believe water entered two probes that report on the flow of air over the aircraft's fuselage.

These so-called angle of attack sensors are essential contributors of data to the A320's "fly-by-wire" system - a computer-controlled electronic interface that replaces manual piloting.

Shortly after taking off, the sensors malfunctioned, presumably when the water in them froze. To their great misfortune, those on the flight deck, concentrating on running through the list of maneuvers, were apparently blind to the danger.

The report calls on airlines to reinforce training for these so-called "non-revenue" flights and exercise greater vigilance in maintenance. For all its 222 pages, it leaves unanswered the question of how closely companies will follow these guidelines, at a time of ever fiercer competition and cost-cutting.

Two sources on the inquiry panel complained that Air New Zealand had tried again and again to resist accusations of pilot error as the investigation unfolded.

"They wanted something slightly different" to emerge, said one. "It could be that Air New Zealand doesn't like the outcome, but they should look into their own procedures rather than question the inquiry."

Another source said Air New Zealand should "stop deflecting" criticism of its practices.

"Small state operators are particularly sensitive about safety and when they make mistakes, it doesn't look good. What an airline should do after an accident is definitely realise that in order to improve, you have to accept the findings," he said.

The head of the BEA, Jean-Paul Troadec, told the Herald the best thing Air New Zealand could do now is "better preparation for this type of flight. When they have these type of flights with people from other airlines they should have better preparation."