Inbuilt Flaws in big single-engined Cessna Commuter Planes?

By Don Phillips International Herald Tribune

MONDAY, JUNE 13, 2005

Not one of the 2,500 most recently developed airliners built by Airbus and Boeing has ever crashed with passengers aboard.

In fact, among the most recently developed Airbus A330 and A340 and Boeing
777 and 737 models, only one aircraft has been lost - an A330 that crashed on June 30, 1994, during a test flight with a new computer control system.

"A remarkable thing has happened to the industry," said Walt Gillette, a Boeing vice president who now heads development of the new 787 Dreamliner.

It has taken the past half-century, or half the history of human flight, Gillette said, but civil aviation has at last reached a point where humans and airplane instruments truly work in harmony.

Aircraft design, cockpit design and safety systems have matured. Passengers may complain about cramped seating and plastic food, but up front in the cockpit, there has been a revolution.

Much of the new technology is less than a decade old, and the next generation of airliners, the A380 and the 787, will take the revolution even further.

"The A380 cockpit is paving the way for new-generation cockpits," said Debra Batson, spokeswoman for Airbus. "The display system interactivity improves the friendliness of the human-machine interface, giving pilots a better awareness of the aircraft systems status."

Safety improvements have often come about in response to disasters. One of the aims in aviation today is to get away from this "crash mentality" and attempt to identify possible causes of crashes before they happen.

Sadly, the two greatest leaps forward in safety in the past two decades have resulted from crashes. Even more sadly, pioneers in aviation safety were beating the drum for technology that could have prevented those disasters. Only after hundreds of people died did governments and airlines take action.

On Aug. 2, 1985, as an DELTA AIR LINES Lockheed L1011 TriStar approached the Dallas-Fort Worth airport, pilots noted that there was a thunderstorm in the distance but were not otherwise concerned. On final approach, the plane suddenly lost lift, bounced off a highway where it hit a car and then crashed. A total of 135 people were killed.

Miles away in Denver, John McCarthy of the National Center for Atmospheric Research said he knew instinctively that the L1011 had been destroyed by a massive downward burst of air that spread out as it hit the earth. This shaft of air, called a microburst, hits an aircraft that flies into it first with a violent headwind that slows it down, followed by a strong tailwind that robs it of lift.

McCarthy and a few allies, including Alan Mulally, then a senior safety executive and now president, of Boeing, had been trying to persuade the U.S.
Federal Aviation Administration and the airlines that microbursts posed a serious threat. But the agency had refused to believe them until the Dallas crash finally galvanized the agency into action, documents from the time showed.

Now, most major airports are equipped with sophisticated wind-shear detectors, and pilots are trained to handle their aircraft in a microburst. Many aircraft are also equipped with onboard wind-shear detectors.

Only one microburst crash has occurred since Dallas - a US Airways DC-9 went down at Charlotte, North Carolina on July 2, 1994 - and other, mostly human, factors played a contributory role.

Still another accident, on Dec. 21, 1995, in Colombia, propelled the adoption of the enhanced ground proximity warning system, one of the most important safety devices in the history of aviation.

A total of 163 people were killed when an American Airlines Boeing 757 crashed into a 2,750-meter, or 9,000-foot, ridge as it descended a mountain valley toward Cali after a flight from Miami.

An investigation showed that the crew had misprogrammed the plane's autopilot to fly toward a radio beacon hundreds of miles to the south. When the plane turned off its route, the crew did not initially notice, on a moonless night over an unpopulated area with no lights on the ground.

After the crew recovered control from the autopilot and began a turn back on course, they did not realize that they were below the level of the ridge.

When the plane's ground proximity warning system sounded, the crew began a climb. But with only a few seconds of warning, they had too little time to clear the top of the ridge.

American Airlines responded with a program to re-equip its fleet with the enhanced warning system, pioneered by an aviation safety engineer, Don Bateman of Allied Signal, now a part of Honeywell. Many corporate jets already had the device, but most airlines had been reluctant to incur the cost of upgrading from warning systems that they had installed only a few years earlier.

Other airlines have since followed suit, and enhanced ground proximity warning systems are now required across most of the developed world, including Europe and the United States. More than 30,000 aircraft are now fitted with the system, a remarkable piece of equipment made possible by the digital age and the end of the cold war, when formerly secret maps became available from the former Soviet Union and the U.S. military.

Inside all such systems is a small digital map of the world, highly detailed, with exact elevations and exact locations of all airports. Through satellite and other navigation devices, the onboard computers know exactly where and how high the aircraft is, and the system can provide a full two minutes' warning if a plane may be on a collision course with high ground. If the pilots fail to notice from the map, synthetic voices loudly warn them, first in a calm tone and later more bluntly, to "Pull Up! Pull Up!"

There is no longer any reason for a pilot to be lost anywhere in the world.

It was not always so, as one mostly forgotten incident showed.

On Sept. 5, 1995, Northwest Airlines Flight 52 from Detroit to Frankfurt, with 241 people aboard, landed by mistake at Brussels, apparently after a computer had been wrongly programmed.

One of the odder quirks of the incident was that many passengers realized they were landing in Brussels because they could see where they were on the map displayed on the screens in the cabins. Passengers in fact alerted the flight attendants, who assumed that the cockpit crew members knew what they were doing and decided not to disturb them.

In the end, it turned out, only the pilots were lost.