Landing protocol lapses seen in crash-landing -WSJ

Movable panels on the front and rear edges of the wings of the Caribbean Airlines (CAL) jet that overshot the runway at the Cheddi Jagan International Airport (CJIA) on July 30 were apparently not extended as required before touchdown and crash investigators believe excessive speed and other suspected lapses in landing procedures caused the accident, the Wall Street Journal reported last night.

Preliminary findings by investigators, according to industry and government officials, point to pilot error rather than mechanical or other system malfunctions, the WSJ report said. A source close to the investigations had also told Stabroek News last week that preliminary investigations point to pilot error as the main contributing factor to Caribbean Airlines Flight 523 overshooting the runway at the CJIA.

The source had said that information from the flight recorders as well as marks on the runway confirmed that the jet touched down close to halfway along the length of the runway.

The WSJ report last night, citing unnamed officials, said that eyewitness accounts and data retrieved from the plane’s data-recorders indicate the twin-engine Boeing aircraft landed too fast and too far down the runway.  Stabroek News’ source had said that the preliminary investigations revealed that the aircraft had touched the runway surface close to halfway down the length of the main Runway O6 at the CJIA. The aircraft touched down between two taxiways codenamed Alpha and Bravo which aircraft such as the Boeing 737 would normally use to exit the runway.

At about 1:32am on July 30, CAL Flight 523 overshot the runway at the CJIA and hurtled through the perimeter fence of the airport before the jet broke in two. There were 162 passengers and crew onboard the Boeing 737-800 aircraft at the time of the crash. There were no fatalities.

The WSJ reported that Director General of the Guyana Civil Aviation Authority, Zulfikar Mohamed, in two separate interviews last week, said that the cockpit crew of Flight 523 reported no problems to air-traffic controllers on approach and data analyzed by investigators so far also doesn’t highlight any major system malfunctions. The comments played down theories that hydraulic or mechanical problems played a significant role in the accident, the report said.

According to the report, Mohamed also gave the strongest sign yet that at least some investigators believe that movable panels on the front and rear edges of wings—essential to decelerate most airliners during descents—apparently weren’t extended as required before touchdown. “It appears that way,” Mohamed said, based on early findings and informal discussions with U.S. and other investigators.

The article noted that photographs taken after the accident do not show either sets of panels, called flaps and slats, extended on the plane. Mohamed was quoted as saying that investigators found the handle in the cockpit, normally used to extend the flaps, in the up position, which would be consistent with the panels not being extended. “The handles certainly may have been in a position they shouldn’t have been,” he said.

However, he told the WSJ that investigators still have to rule out the possibility that the wing panels could have retracted after touchdown, or the rescue crew could have inadvertently moved the flap handles when they were removing the plane’s injured pilot or other survivors.

Safety experts and people familiar with the investigation, who spoke with the WSJ, discounted those possibilities.

Completely retracting flaps fully extended for touchdown on a relatively short runway such as the one in Guyana, experts said, typically would take longer than Flight 523 remained on the runway. Furthermore, passenger-evacuation procedures usually require pilots to extend, rather than retract, flaps.

Press officials for manufacturer Boeing Co. and the U.S. National Transportation Safety Board, which has a big role in the investigation, declined to comment, the WSJ said.

The report said that it would be highly unusual for an experienced captain, such as the one who commanded the CAL flight, to fail to extend flaps prior to landing. Such a mistake, according to safety experts, normally would prompt obvious and repeated warning in the cockpit, and the plane would be extremely difficult to fly at normal approach speed.

The WSJ noted that images of the four-year old Boeing 737’s broken fuselage—along with reports of terrified passengers scrambling out of the wreck—sparked widespread public and industry interest in the causes of the accident.

Guyana is formally in charge of the investigation, but much of the technical work relies on help from Boeing and the U.S. safety board. The board sent seven staff members to the site, “an unusually large contingent for a crash without fatalities, underscoring that local officials are relying heavily on the safety board’s expertise,” the report said.

It pointed out that the airport experienced light rain around the time of the accident, but visibility apparently was good.

Investigators, among other things, are trying to determine if some distraction in the cockpit could have resulted in improper landing procedures, the report said.

The WSJ said that the crash here illustrates the persistent hazards of so-called runway excursions: accidents and serious incidents in which airliners careen off runways, often because pilots landed too fast, touched too far down the strip, or didn’t recognize the difficulty of stopping on wet, slushy or snow-packed surfaces.

In recent years, regulators and safety groups have focused particularly on preventing runway accidents in which poor pilot decision-making results in landing aircraft being unable to stop safely.

According to statistics compiled by manufacturer Boeing Co., runway accidents involving Western-built aircraft, including excursions during takeoffs and landings, accounted for more than 970 fatalities from 2001 to 2010. A report released last year by European air-traffic control officials cited runway excursions as “the most common type of accident reported annually” in the region and around the world, with landing overruns accounting for 77% of all such accidents in that category, the WSJ reported.

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