Results
2011-19-01: We are adopting a new airworthiness directive (AD) for the products listed above that would supersede an existing AD. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: In service experience has shown a number of events of pin to socket arcing at the Integrated Drive Generator (IDG) feeder cable pylon/nacelle interface connector. The fretting corrosion phenomenon was identified to be the root cause of the pin to socket arcing. Investigation has identified a non-optimised electrical harness installation as a contributing factor to this phenomenon that could lead to electrical arcs with possible electrical flickering. * * * * * [S]ome operators reported cases of Display Unit (DU) flickering, despite the fact that the engines installed did not belong to the affected batch,and that these aeroplanes had been modified to incorporate one of * * * two terminating actions, * * *. [S]ome intermittent electrical power supply interruptions may not be detectable by the electrical power monitoring system, thereby preventing an automatic disconnection of the failed generator. * * * * * The unsafe condition is transient loss of certain systems, which could result in the reduced ability of the flightcrew to cope with adverse flight conditions. This AD requires actions that are intended to address the unsafe condition described in the MCAI.
95-22-07: This amendment supersedes Airworthiness Directive (AD) 83-26-05 and AD 86-15-08, which currently require repetitively inspecting the horizontal stabilizer attachment fittings for cracks or looseness on certain de Havilland DHC-6 series airplanes, and, if a cracked or loose part is found, modifying the horizontal stabilizer. This action retains the repetitive inspection requirement of the existing AD's, requires incorporating an improved modification for airplanes with a certain modification design as terminating action for the repetitive inspections, and making these inspection-terminating modifications optional for other affected airplanes. Reports of loose horizontal stabilizer attachment fittings on airplanes incorporating the inspection-terminating modifications required by AD 83-26-05 prompted this action. The actions specified by this AD are intended to prevent separation of the horizontal stabilizer from the airplane caused by a cracked attachment fitting, and subsequent loss of control of the airplane.
95-22-02: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Jetstream Model ATP airplanes, that currently requires daily and/or pre-flight cleaning and inspections to detect damaged main landing gear (MLG) wheel bearings and replacement of discrepant parts. That AD was prompted by reports of failure of the MLG wheel bearings. This action requires an additional inspection, in lieu of the pre-flight inspection, for certain airplanes. This action also requires the accomplishment of a terminating modification that eliminates the need for daily and pre-flight inspections. The actions specified by this AD are intended to prevent failure of the MLG wheel bearing, which could result in detachment of a MLG wheel from the airplane.
2008-13-01: We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as: During scheduled X-ray inspections of Fokker 50 (F27 Mark 050) engine mounting frames, welding defects were discovered. In two forward frames and one aft frame, defects were found in a total of 4 weld locations. Investigation showed that during manufacture of the frames, when the tubes were welded to the end fittings, unintentional sideways movement of the electric arc resulted in some welds running beside the borderline for a part of the tube circumference. Where a weld runs beside the borderline, there is no connection between tube and end fitting for that part of the circumference, directly affecting the structural integrity of the engine mounting frame connections. The defective welding process appears to have happened at some of the welds in an unknown number of engine mounting frames. This condition, if not corrected, could lead to failure of the engine mounting frame in cases where multiple welds are severely affected, potentially resulting in in-flight loss of an engine. * * * This AD requires actions that are intended to address the unsafe condition described in the MCAI.
2005-07-15: The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 and 440) airplanes. This AD requires modification of the Auxiliary Power Unit (APU) cooling air exhaust. This AD is prompted by reports of incomplete drainage of the APU enclosure. We are issuing this AD to prevent a negative pressure condition from developing in the APU enclosure when the APU is operating on the ground, which could create a potential fire hazard if flammable liquid leakage occurs inside the APU enclosure and cannot be drained overboard.
95-21-14: This amendment supersedes Airworthiness Directive (AD) 83-18-03, which currently requires repetitively inspecting the tailplane outboard hinge assembly on certain de Havilland DHC-6 series airplanes, and replacing any cracked tailplane outboard hinge assembly. The Federal Aviation Administration's policy on aging commuter-class aircraft is to eliminate or, in certain instances, reduce the number of certain repetitive short-interval inspections when improved parts or modifications are available. This action requires eventually modifying the tailplane outboard hinge arm and tailplane hinge plate with parts of improved design (Modification No. 6/1799) as terminating action for the currently required repetitive inspections. The actions specified by this AD are intended to prevent tailplane failure caused by cracks in either outboard hinge arm or the hinge plate, which, if not detected and corrected, could result in loss of control of the airplane.
95-21-08: This amendment adopts a new airworthiness directive (AD), applicable to Boeing Model 757 series airplanes, that requires modification of the engine fuel indication circuits. This amendment is prompted by numerous reports of false indications of engine fuel valve faults, which have led to the flight crew conducting rejected takeoffs (RTO). The actions specified by this AD are intended to reduce such false indications and the flight crew's consequent execution of an RTO at high speed during takeoff roll, which could result in the airplane overrunning the runway, damage to the airplane, and injury to airplane occupants.
2008-14-07: The FAA is superseding an existing airworthiness directive (AD) for certain fuel injected reciprocating engines manufactured by Lycoming Engines. That AD currently requires inspection, and replacement if necessary, of externally mounted fuel injector fuel lines. This AD requires the same actions but adds additional engine models and clarifies certain compliance time wording. This AD also exempts engines that have a Maintenance and Overhaul Manual with an Airworthiness Limitations Section that requires inspection and replacement, if necessary, of externally mounted fuel injector lines. This AD results from Lycoming Engines revising their Mandatory Service Bulletin to add new engine models requiring inspection, and from the need to clarify a repetitive inspection compliance time. We are issuing this AD to prevent failure of the fuel injector fuel lines that would allow fuel to spray into the engine compartment, resulting in an engine fire.
2005-07-17: The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-102, -103, -106, -201, -202, -301, -311, and-315 airplanes. This AD requires revising the airplane flight manual to include applicable procedures to follow when the flightcrew receives abnormal indications of airspeed, altitude, or vertical airspeed. This AD also requires modifying the static system. This AD is prompted by a report of a leak in the static pressure system, which could result in loss of the static systems and consequent erroneous data displayed on the pilot's flight instruments. We are issuing this AD to advise the flightcrew of applicable procedures in the event of abnormal indications of airspeed, altitude, or vertical airspeed; and to prevent leaks in the static system, which could result in the loss of critical flight information that could result in reduced controllability of the airplane or controlled flight into terrain.
95-21-07: This amendment adopts a new airworthiness directive (AD), applicable to Lockheed Model L-1011-385 series airplanes, that requires modifications of various fluid drainage areas of the fuselage. This amendment is prompted by incidents involving corrosion and fatigue cracking in transport category airplanes that are approaching or have exceeded their economic design goal; these incidents have jeopardized the airworthiness of the affected airplanes. The actions specified by this AD are intended to prevent degradation of the structural capabilities of the affected airplanes due to problems associated with corrosion.