The European Aviation Safety Agency (EASA) is giving operators of Sogerma pilot seat-equipped Airbus A300-600, A300-600ST and A310 aircraft until 9 May to deactivate the horizontal and vertical electrical adjustment controls on the seats.
The mandate was spawned by a report of an A300-600 co-pilot seat sliding back uncommanded to its rearmost position during takeoff, says EASA. Following a change out of the seat's horizontal movement actuator, the aircraft was put back in service, but the seat again slid back during the next takeoff.
According to the airworthiness directive (AD) issued 9 April, an investigation of the two removed actuators revealed that the clutch was broken inside the shaft, unlocking the seat horizontal movement.
"An unwanted movement of the pilot or co-pilot seat in the horizontal direction is considered as potentially unsafe, especially during the take off phase when the speed of the aeroplane is greater than 100kt and until the landing gear is retracted," EASA states in the AD.
Along with deactivating the seats entirely, the agency provides for two alternative interim actions that can be implemented to restore partial or full use of the electrical controls until a final airworthiness directive (AD) is issued at a later date.
Source: Air Transport Intelligence news
