Maintenance errors in the flight control system have been confirmed as the cause of two fatal Raytheon Beech 1900D accidents and one incident this year, even though the task was different in each case, according to the US National Transportation Safety Board (NTSB). The effect in the two fatal cases was loss of control, but in the third event the captain aborted take-off because of a jammed elevator control.

Updating the two more recent events - the 26 August Colgan Air accident shortly after take-off from Yarmouth, Massachusetts and the 16 October CommutAir incident at Albany, New York - the NTSB says both showed errors in pitch control system maintenance.

Meanwhile, Raytheon has revised the 1900 series maintenance manuals to clarify "procedures and illustrations related to the elevator trim system". In the Colgan Air accident the flight data recorder shows that the elevator trim moved to a pitch-down setting soon after unstick and remained there until impact. In the CommutAir incident the technician had to remove the elevator trim control wheel, but failed to re-index it correctly when refitting it, so when the elevator trim was neutral the wheel showed nose-down trim.

Source: Flight International