Federal Aviation Administration May 18, 2021 – Federal Register Recent Federal Regulation Documents

The FAA is adopting a new airworthiness directive (AD) for all The Boeing Company Model 737-300, -400, and -500 series airplanes. This AD was prompted by a flap synchro wire failure that may go undetected by the autothrottle (A/T) computer. This AD requires repetitive BITE (built-in test equipment) tests of the A/T computer to detect a flap synchro wire failure, and corrective action if necessary. The FAA is issuing this AD to address the unsafe condition on these products.

The FAA is superseding Airworthiness Directive (AD) 2019-03-12 for certain Airbus Helicopters Model EC225LP helicopters. AD 2019-03-12 required repetitively inspecting, cleaning, and lubricating each life raft inflation cylinder percussion system bellcrank (bellcrank). This new AD continues to require the actions specified in AD 2019-03-12, and requires replacing any affected bellcrank with a serviceable bellcrank, which terminates the repetitive actions. This AD was prompted by reports of jammed bellcranks in the life raft jettison inflation cylinder percussion system. The actions of this AD are intended to address an unsafe condition on these products.

The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus SAS Model A330-200, -200 Freighter, -300, -800, and -900 series airplanes; and Model A340-200 and -300 series airplanes. This proposed AD was prompted by reports of incorrect installation of the lower attachment parts of the trimmable horizontal stabilizer actuator (THSA). This proposed AD would require doing a detailed inspection of the THSA lower attachment parts for discrepancies and corrective action if necessary, and would prohibit using earlier versions of certain airplane maintenance manual (AMM) tasks, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference. The FAA is proposing this AD to address the unsafe condition on these products.

The FAA proposes to adopt a new airworthiness directive (AD) for certain Airbus Helicopters Model AS350B, AS350BA, AS350B1, AS350B2, AS350B3, AS350D, AS355E, AS355F, AS355F1, AS355F2, AS355N, and AS355NP helicopters. This proposed AD was prompted by a report of reduced yaw control, during an approach for landing, that resulted from rupture of the tail rotor gearbox (TGB) actuating rod and uncoupling of the steel sleeve from inside the external aluminum tube. This proposed AD would require dye penetrant inspecting certain TGB actuating rods for a crack, and depending on the inspection results, replacing the TGB actuating rod, as specified in a European Union Aviation Safety Agency (EASA) AD, which is proposed for incorporation by reference (IBR). This proposed AD would also require marking each TGB actuating rod, reporting information, and, for certain helicopters, ensuring the correct interface between certain TGB actuating rods and bearings. The FAA is proposing this AD to address the unsafe condition on these products.