NY Times article: Airbus Criticized for Hudson Crash

[Henry Tenby]

The following was reported by the NY Times today:
http://www.nytimes.com/2010/05/05/nyregion/05ntsb.html

Everybody got out alive when a US Airways Airbus A320 hit the Hudson River 16 months ago, but the airplane manufacturer’s assumptions about how it would behave in such circumstances were unrealistic and the crew’s emergency manual was inappropriate, according to information released by the National Transportation Safety Board on Tuesday morning.

The quick reaction of the crew on Flight 1549 played a large role in averting a great loss of life, but other factors were critical, too. Among the plane’s saving graces was that it happened to have flotation devices, even though they were not required for that particular flight, the board said.

“It was the outcome of a perfect storm of circumstances,” said Deborah A.P. Hersman, chairwoman of the board, which was meeting to approve a final report on the crash-landing. “If the visibility had been poor; if the flight had simply met, rather than exceeded, safety equipment standards; if the incident took place over open water where rescue vessels were not at hand; if even a single element had changed, the ditching could have ended not as a miracle but as a tragedy.”

The captain, Chesley B. Sullenberger III, and the first officer, Jeffrey B. Skiles, were widely praised after the crash, as were the flight attendants, one of whom was among those seriously injured. Ms. Hersman echoed the praise but said, “The heroism of the flight crew was a necessary, but not sufficient, element.”

The plane took off from La Guardia Airport on Jan. 15, 2009, and quickly lost both engines after they were struck by birds. Five minutes and 8 seconds later, the plane came down in the river between Weehawken, N.J., and Midtown Manhattan. All 150 passengers and five crew members survived, with five seriously injured.

The board is expected to spend most of Tuesday discussing what recommendations to make, but early testimony, and documents released just before the hearing began, made several sobering points.

One was that cockpit instruments did not give a clear indication of the status of the engines. The emergency manual stressed attempting to restart them, but on Flight 1549 it was impossible. So any time the crew members spent trying to restart the engines — with only a few moments to decide what to do — was wasted.

In addition, aviation authorities approved the airplane design based on the idea that a pilot could bring it down at a rate of about 3.5 feet per second, which would allow a touchdown without structural damage. But that descent rate may be unrealistic, experts said. The Airbus A320 came down at about 13 feet per second, causing severe hull damage, which resulted in the plane’s taking on water.

The approval was based on assumptions that all four floor-level exits would be available, two front and two rear, and that over-wing exits would not be used. But in the Hudson River crash, passengers in the emergency rows took matters into their own hands and opened the over-wing exits. Because there were no rafts located over the wings, passengers who exited through those openings could have been marooned in the frigid water had rescue boats not arrived to save them before the plane sank, experts said.The passengers also evidently assumed that the wing slides were also rafts, but they are not, the Association of Flight Attendants pointed out.

Ms. Hersman noted that the airplane met the rules for operation more than 50 miles from shore, notably by carrying flotation devices. This was purely by chance, because the route to Charlotte, N.C., the intended destination, did not require flotation devices, even though most airports have at least one approach over water, she said.

Documents and comments by experts reasserted the idea that Captain Sullenberger’s decision to land the plane in the water was sound. Some pilots and experts have noted that at the point when the engines quit, the runways of La Guardia might have been closer, but it might have been impossible for the crew to know that.

Airbus, in a document released Tuesday, said, “Although an emergency return to La Guardia Runway 13 was technically feasible from an aircraft flight performance point of view, the emergency landing on the Hudson seems the most appropriate decision.”

Accident investigation authorities in France, who had a role in the proceedings because the plane was built there, said a return to La Guardia was “theoretically feasible,” but “the captain seemed to have pondered the risk of not reaching the runway and considered the high urbanization of the airport surroundings.”