Fatigue resulting from insufficient rest and a long duty day was a contributory cause of the 19 October 2004 fatal commuter aircraft crash at Kirksville, Missouri, according to the US National Transportation Safety Board's report.
The Corporate Airlines BAe Jetstream 32 twin turboprop crashed on a night final approach in poor visibility at the end of a long duty day, killing all but two of the 15 people on board.
The NTSB report, criticising Federal Aviation Administration flight time limitations for being unscientific, says crew rest and duty time for the fatal flight to Kirksville had been within the legal requirements.
However, given "the less than optimal overnight rest time available, the early reporting time for duty, the length of the duty day, the number of flight legs, the demanding conditions - non-precision approaches flown manually in conditions of low ceilings and reduced visibilities - encountered during the long duty day and the two previous days, it is likely that fatigue contributed to the pilots' degraded performance and decision making", the report says.
The crew were on their sixth sector of a 15h day, and the final leg was operating late. The NTSB says the crew paid insufficient attention to their descent profile on the non-precision approach because they were straining to see the approach lights.