Wednesday, December 12, 2007

Air France plane 'too high and too fast' before crash

Globe and Mail Update
December 12, 2007 at 11:07 AM EST
Air France Flight 358 came in too high and too fast when it overshot a runway and crashed in heavy rain at Toronto's Pearson International Airport in August 2005, a final report says.
The Airbus A340 "came in too high and too fast, touching down almost halfway along the wet and slippery runway. It simply ran out of room,” said Wendy Tadros, chairwoman of Canada's Transportation Safety Board, which probed the crash.

"The Air France crew did not calculate the landing distance required for the conditions at destination,” she said. "In a few short minutes, the passengers went from the relative calm at the end of a long flight to an emergency evacuation.”

Ms. Tadros noted that since the Air France crash, 10 large aircraft have gone off runways around the world in bad weather.
The TSB made seven recommendations, including:
• mandatory international standards limiting landings during thunderstorms
• better pilot training on landings in poor weather
• requirement that crews calculate the landing distance upon arrival at their destination so they will know the margin of error
• requirement of a 300-metre safety area or an alternative means of stopping aircraft at the end of Canadian runways
• that passenger safety briefings include clear directions to leave all carry-on baggage behind during evacuations
"There can be no doubt the story of Air France flight 358 is the story of survival – the survival of all 309 people on board," Ms. Tadros said.
"Even so, I'm certain all on board that day would tell you that no one should have to go through what they went through."
The report elaborates on previously published findings from the investigation, including that the Air France pilots made no effort to abort the landing, which is standing operating procedure when there is insufficient runway on which to land.
Although two crew members and nine passengers were seriously injured in the incident, all 309 people on board the flight from Paris survived, scrambling into a rain-soaked ravine just before a spreading fire engulfed the plane. Evacuating the jet took less than two minutes, even though four of eight exits were blocked or unavailable and despite the fact that many passengers disobeyed instructions and took their hand baggage with them.
A TSB interim investigation update released in November, 2005 amounted to an exoneration of the aircraft, saying there was nothing wrong with its brakes or other key systems as the plane landed just after 4 p.m. on a day marred by heavy thunderstorms and shifting wind gusts.
"No significant anomalies of the aircraft system have been found to date," the interim report said. "No problems were detected with the flight controls, spoilers, tires and brakes, or the thrust reversers."
The earlier report also made clear that air-traffic control had properly and fully warned the Air France pilots of the wet runway and poor braking conditions and that the plane had plenty of fuel either to abort the landing and try again in Toronto or to divert to its designated alternative, Ottawa.
Without pointing to pilot error – the investigation is not intended to assign blame – the report makes it clear that the pilots knew they were too high and too fast as they crossed the beginning of the runway, and that they should have known the big, four-engine A340, weighing 185 tonnes, would need about two kilometres to stop.

The pilots disconnected the autopilot about 100 metres above the ground and the co-pilot landed the aircraft manually.

"The aircraft then went slightly above the glide slope" – the ideal path that put the aircraft down in the first few hundred metres of the runway – "and arrived over the runway threshold at an estimated height of 100 feet," twice the normal height expected at that point, the report said.

Not only was the plane too high, it was going too fast. "Indicated airspeed increased from 139 knots to 154 knots."

Instead of landing the aircraft at 260 kilometres an hour in the first few hundred metres of runway, the crew touched down at about 285 km/h and almost halfway down a 2.7-kilometre runway.

Air-traffic control had informed the crew of AF358 that aircraft landing on the same runway just ahead of it had reported poor braking conditions and shifting winds.

Source: The Globe and Mail

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