AOPA Thwarted, Too
AOPA also argued that aircraft owners should be allowed to continue to use their engine until reaching time-for-overhaul based on hours, without any “arbitrary” calendar deadline. Some owners may have only a few hours on their engine and reach the 12-year limit well before an overhaul is needed, AOPA said. The FAA disagreed with that one, too. “We re-evaluated the risk that this unsafe condition presents to aircraft and have determined that adequate risk mitigation can only be achieved by establishing an end limit for crankshaft removal based on years since a crankshaft enters service,” the FAA said. Variations in the crankshaft anomalies make it impossible to predict when failure might occur, according to the AD.
AOPA also argued that aircraft owners should be allowed to continue to use their engine until reaching time-for-overhaul based on hours, without any "arbitrary" calendar deadline. Some owners may have only a few hours on their engine and reach the 12-year limit well before an overhaul is needed, AOPA said. The FAA disagreed with that one, too. "We re-evaluated the risk that this unsafe condition presents to aircraft and have determined that adequate risk mitigation can only be achieved by establishing an end limit for crankshaft removal based on years since a crankshaft enters service," the FAA said. Variations in the crankshaft anomalies make it impossible to predict when failure might occur, according to the AD. If an owner or operator has data to justify an extension of the hourly limit and/or the calendar end-limit, the FAA said it will consider applications for Alternate Means of Compliance.