Friday, October 06, 2006

Software testing for some airlines raises concerns

"As a Malaysia Airlines jetliner cruised from Perth, Australia, to Kuala Lumpur, Malaysia, one evening last August, it suddenly took on a mind of its own and zoomed 3,000 feet upward.

The captain disconnected the autopilot and pointed the Boeing 777's nose down to avoid stalling, but was jerked into a steep dive. He throttled back sharply on both engines, trying to slow the plane. Instead, the jet raced into another climb. The crew eventually regained control and manually flew their 177 passengers safely back to Australia.

Investigators quickly discovered the reason for the plane's roller-coaster ride 38,000 feet above the Indian Ocean. A defective software program had provided incorrect data about the aircraft's speed and acceleration, confusing flight computers. The computers had also failed, at first, to respond to the pilot's commands. Within weeks Boeing Co. warned airlines world-wide to install a fix provided by Honeywell International Inc., which makes the flight computers and supplied the faulty software."

The article goes on to describe other software testing failures and incidents on aeroplances including:
1. In February 2005, multiple computers meant to back each other up mistakenly cut the flow of fuel to two of the four engines on a packed Virgin Atlantic Airbus A340 headed from Hong Kong to
London. The crew made an emergency landing at Schiphol Airport outside Amsterdam. British investigators have recommended design changes, including better warnings on fuel levels. Virgin Atlantic says it is cooperating with the investigation and the safety of the passengers was never threatened.
2. In October 2005, a 90-second computer hiccup aboard a British Airways Airbus A319 on a night flight from London to Budapest temporarily shut off nearly all the cockpit lights and electronic displays, along with radios and autopilot systems. British investigators say they have unearthed four similar cases on Airbus jets.
3. During a test flight of a new jetliner made by Brazilian plane manufacturer Empresa Brasileira de Aeronáutica SA, or Embraer, the cockpit screens went black for a minute because of a software glitch. The FAA has since ordered programming and operational changes to the planes. Embraer says it has fixed the problems.

4. Similar computer malfunctions have caused all cockpit screens to flicker or go dark momentarily in some smaller jets used by business executives. Regulators and manufacturers are working to prevent the same type of glitches on other high-end corporate aircraft.

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