By Mary Kirby & John Croft
Probe into last August's Comair CRJ100 accident at Lexington questions work schedules and rest management
As evidence of air traffic controller fatigue comes to light in the investigation probing last August's crash of a Comair Bombardier CRJ100 at Lexington Blue Grass airport in Kentucky, the US National Transportation Safety Board has called for ATC work-scheduling policies to be reviewed by the Federal Aviation Administration.
The NTSB has released two letters to FAA administrator Marion Blakey relating to its investigation, in which the subject of low pilot alertness is also in the frame as a possible contributory factor.
Comair flight 5191 crashed in pre-dawn darkness on 27 August 2006 after the pilots mistakenly attempted to take off on runway 26, a 1,100m (3,500ft) general aviation runway, rather than the cleared 2,140m long runway 22. The aircraft failed to become airborne before hitting an airport perimeter fence and trees. Of 47 passengers and three crew, only the first officer survived. The NTSB has learned that the single air traffic controller in Blue Grass tower who cleared the accident aircraft for take-off had worked from 06:30 to 14:30 the day before, then returned 9h later to start work at 23:30. He was still on duty at 06:07 the next morning when the accident occurred. The controller said his only sleep in the 24h before the accident was a 2h nap the previous afternoon between shifts, says the NTSB.
However, it insists that four separate incidents provide "clear and compelling evidence" that controllers sometimes operate when fatigued because of their work schedules and poor management of their rest periods between shifts. Fatigue has contributed to controller errors, the NTSB says. Among those is the 23 March 2006 runway incursion at Chicago O'Hare involving two United Airlines aircraft.
Meanwhile, Comair's president Don Bornhorst, in a document submitted to the NTSB, says: "Comair understands and accepts that the conduct of one of its flightcrews is one of the numerous factors which contributed to this accident...[but there were] multiple systemic weaknesses in the conduct of other individuals and organisations that were links in the causal chain," naming the FAA as one of them.
"Comair...suggests the [NTSB] investigate the FAA's approach to runway airport surveillance. Had the controller on duty been required to devote all his attention to the airport environment while the aircraft was departing, this accident may have been prevented," says Bornhorst.
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