Airbus Set to Warn of Electrical Faults
The Wall Street Journal 11/11/2010
Author: Andy Pasztor
(Copyright (c) 2010, Dow Jones & Company, Inc.)
European jet manufacturer Airbus is drafting a world-wide safety warning about electrical problems that can temporarily shut off primary cockpit displays on its mid-sized jetliners after an incident involving a British Midland International Airbus A321.
The harrowing incident, which occurred in August during a night flight from Khartoum to Beirut, also resulted in the twin-engine jet shuddering, banking steeply on its own and failing to respond to pilot commands over a period of several minutes, according to a report released last week by British accident investigators.
The event is important because for years safety investigators in Great Britain. France, the U.S. and elsewhere have been concerned about electrical-system glitches resulting in dangerous shutdowns of flight-control computers. Many safety experts believe commercial-pilots should receive more training about how to respond to such rare but serious in-flight hazards.
British safety experts previously investigated at least half a dozen other instances in which both the captain and co-pilot of a jetliner temporarily lost their primary flight and navigation displays, as well as computer systems that monitor a broad array of mechanical and electrical systems. Major electrical problems can leave cockpit crews struggling to control highly-computerized aircraft by relying only on standby instruments. But for investigators, such events are notoriously hard to understand and replicate.
On Aug. 21, the six-year old British Midland jet with 49 people aboard was cruising at 36,000 feet over northern Sudan when it suffered a series of major electrical malfunctions. According to a safety bulletin issued last week by the United Kingdom's Air Accidents Investigation Branch, or AAIB, primary flight and navigation displays intermittently disappeared even as the crew was bombarded by a stream of warning messages about various system faults.
The report notes that the pilots reported hearing a persistent "chattering"' sound from circuit breaker panels. Cockpit screens continued to flicker, turned gray and then went blank. Just as suddenly, the pilots later told investigators, the displays briefly returned to normal. The wave of abnormalities continued for several minutes, while the cockpit lights turned on an off by themselves.
The situation became even more serious when the plane's computerized flight-controls reverted to an unusual condition, the automatic thrust system became locked and the aircraft's left wing dropped ``without any flight control input from the crew,'' according to the report. Standby instruments operated normally, and the pilots eventually regained control of the twin-engine airplane.
The AAIB's probe continues, with the cooperation of Airbus and French air-safety officials. But already, investigators have urged Airbus, a unit of European Aeronautic Defence & Space Co. to alert all operators of A320s and similar planes about the potential hazards stemming from such electrical faults.
An Airbus spokesman said the company "is actively working with" government experts "to understand the event fully'' and is "preparing a communication to operators" about the matter.
The Wall Street Journal 11/11/2010
Author: Andy Pasztor
(Copyright (c) 2010, Dow Jones & Company, Inc.)
European jet manufacturer Airbus is drafting a world-wide safety warning about electrical problems that can temporarily shut off primary cockpit displays on its mid-sized jetliners after an incident involving a British Midland International Airbus A321.
The harrowing incident, which occurred in August during a night flight from Khartoum to Beirut, also resulted in the twin-engine jet shuddering, banking steeply on its own and failing to respond to pilot commands over a period of several minutes, according to a report released last week by British accident investigators.
The event is important because for years safety investigators in Great Britain. France, the U.S. and elsewhere have been concerned about electrical-system glitches resulting in dangerous shutdowns of flight-control computers. Many safety experts believe commercial-pilots should receive more training about how to respond to such rare but serious in-flight hazards.
British safety experts previously investigated at least half a dozen other instances in which both the captain and co-pilot of a jetliner temporarily lost their primary flight and navigation displays, as well as computer systems that monitor a broad array of mechanical and electrical systems. Major electrical problems can leave cockpit crews struggling to control highly-computerized aircraft by relying only on standby instruments. But for investigators, such events are notoriously hard to understand and replicate.
On Aug. 21, the six-year old British Midland jet with 49 people aboard was cruising at 36,000 feet over northern Sudan when it suffered a series of major electrical malfunctions. According to a safety bulletin issued last week by the United Kingdom's Air Accidents Investigation Branch, or AAIB, primary flight and navigation displays intermittently disappeared even as the crew was bombarded by a stream of warning messages about various system faults.
The report notes that the pilots reported hearing a persistent "chattering"' sound from circuit breaker panels. Cockpit screens continued to flicker, turned gray and then went blank. Just as suddenly, the pilots later told investigators, the displays briefly returned to normal. The wave of abnormalities continued for several minutes, while the cockpit lights turned on an off by themselves.
The situation became even more serious when the plane's computerized flight-controls reverted to an unusual condition, the automatic thrust system became locked and the aircraft's left wing dropped ``without any flight control input from the crew,'' according to the report. Standby instruments operated normally, and the pilots eventually regained control of the twin-engine airplane.
The AAIB's probe continues, with the cooperation of Airbus and French air-safety officials. But already, investigators have urged Airbus, a unit of European Aeronautic Defence & Space Co. to alert all operators of A320s and similar planes about the potential hazards stemming from such electrical faults.
An Airbus spokesman said the company "is actively working with" government experts "to understand the event fully'' and is "preparing a communication to operators" about the matter.
