Boeing and spoiler actuator manufacturer Smiths Aerospace are voluntarily replacing the supplier's part on all 37 Boeing 737-800 short-field performance aircraft in service and on the production line to prevent possible failures that the US Federal Aviation Administration says could cause a loss of control on take-off.
The emergency airworthiness directive issued by the FAA in March requires crew or qualified personnel to visually verify that spoilers are stowed after every landing or rejected take-off and after any maintenance that deploys the actuators.
The emergency AD was issued after at least two "hardover" failures - or jamming in the up position - were reported. Such a failure could cause "significant roll and consequent loss of control of the airplane", said the FAA at the time.
The AD allows operators to waive the visual inspections by replacing all eight actuators on the 737, an action the regulator says it may ultimately decide to mandate.
The company has so far replaced spoiler actuators on nine aircraft, and plans to finish the remainder by the end of summer, it says. The company is replacing the actuators in the in-service aircraft first.
Source: Flight International
