A final US National Transportation Safety Board (NTSB) report into the fatal crash of Corporate Airline flight 5966 during final approach to Kirksville airport, Missouri on 19 October 2004 confirms that pilot error killed all but two of the 15 people onboard.

Corporate’s British Aerospace Jetstream 32 crashed short of the runway after striking trees. Several of the victims’ families have already filed lawsuits against Corporate, alleging serious procedural deficiencies and lapses in judgment by the flight crew.

“The NTSB today determined that the cause of an aircraft accident in Kirksville, Missouri was the pilots’ failure to follow established procedures and properly conduct a non-precision instrument approach at night in instrument meteorological conditions (IMC). This included their descent below the minimum descent altitude (MDA) before required visual cues were available and their failure to adhere to the established division of duties between the flying and non-flying pilot,” the safety board says in its report.

This failure, adds the NTSB, could be borne from a false confidence produced by current regulations allowing pilots to descend below the MDA. “These regulations can have the unintended effect of encouraging some pilots to descend below the MDA in an attempt to acquire visual cues that will permit them to continue the approach, as evident in this case.”

Corporate’s two pilots are also criticised for their lack of professionalism as well as their failure to adhere to normal protocols. “[T]he pilots failed to follow established procedures to effectively monitor the airplane’s descent rate and height above terrain during the later stages of the approach and relied too much on minimal external visual cues,” says the NTSB.

“Although descent rate and altitude information were readily available through cockpit instruments, both pilots were largely preoccupied with looking for the approach lights.” Also, the pilots’ “failure to establish and maintain a professional demeanor during the flight and fatigue likely contributed to their degraded performance,” adds the NTSB.

According to the report, the crew also breached sterile cockpit regulations below that should have been enforced below 10,000ft (3,000m). This “reflected a demeanor and cockpit environment that fostered deviation from established standard procedures, crew resource management disciplines, division of labor practices, and professionalism, reducing the margin of safety well below acceptable limits during the accident approach.”

Fatigue was also a contributory factor. “Through its investigation, the board learned that 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 and the demanding flying conditions were factors that affect any fatigue that the pilots may have experienced,” says the NTSB on the crash, which was the sixth and final flight of the day for the two crew.

“This supports the board’s finding that fatigue likely caused the degraded performance and subsequent decision making.”

To avoid future accidents, the NTSB recommends that all scheduled operators retrain crews on the importance of sterile cockpit environments, incorporate the constant-angle-of-approach technique into their non-precision approaches, and prohibit the practice of descending below MDA unless conditions allow for clear visual approach.

Corporate, which now operates as RegionsAir, was not immediately available for comment.

DARREN SHANNON / WASHINGTON, DC

Source: Flight International