In their investigation into the cause of the fatal DHC-6 Twin Otter accident in French Polynesia in August, 2007, the French BEA discovered some problems relating to the elevator control cables. Two stainless steel cables were found to be severely worn due to friction. These zones of wear were difficult to identify without a thorough examination.
Consequently, the BEA recommends Transports Canada and the European Agency of Air Safety:
– to ask the owners to inspect the stainless steel pitch control cables of DHC-6 Twin Otter planes as soon as possible, especially the zones of friction were the cables contacts cable guides;
– to determine if steel-carbon cables are also suitable for pitch control. (BEA)