Pilatus PC-12

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by a report that the emergency exit door could not be opened from inside an airplane. This AD requires modification of the passenger service unit (PSU) trim panel if dual lock fastener tapes are not installed. This AD also prohibits the installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by a report that, during an engine start on the ground, the airplane battery voltage dropped to a value that resulted in an avionic system shutdown. This AD requires incorporating a temporary revision (TR) into the existing pilot's operating handbook (POH) for the affected airplanes to provide operators with instructions for an enhanced engine start procedure. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by a report of the stall warning protection system (SWPS) engaging when not appropriate. This AD requires updating operational software and incorporating a pilot's operating handbook (POH) temporary revision (TR). This AD also prohibits the installation of affected software. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47G airplanes. This AD was prompted by a report that a brake shuttle valve (BSV) on a production airplane shuttled and isolated the brake line to the left- hand (LH) brake, which resulted in brake lockup. This AD requires replacement of the LH and right-hand (RH) brake pipe assemblies and also prohibits the installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is superseding Airworthiness Directive (AD) 2023-12- 17, which applied to Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC- 12/45, PC-12/47, and PC-12/47E airplanes. AD 2023-12-17 required revising the airworthiness limitation section (ALS) of the existing aircraft maintenance manual (AMM) or Instructions for Continued Airworthiness (ICA) for your airplane by introducing new and more restrictive instructions and maintenance tasks as specified in the component limitations section, which includes repetitive inspections for cracks in the lower main spar connection of the horizontal stabilizer. Since the FAA issued AD 2023-12-17, the FAA has determined that new or more restrictive airworthiness limitations are necessary. This AD requires revising the ALS of your existing AMM or ICA and your existing approved maintenance or inspection program, as applicable, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is superseding Airworthiness Directive (AD) 2022-19-03 which applied to Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. AD 2022-19-03 required incorporating new revisions to the airworthiness limitation section (ALS) of the existing airplane maintenance manual (AMM) or Instructions for Continued Airworthiness (ICA) to establish a 5-year life limit for certain main landing gear (MLG) actuator bottom attachment bolts and new life limits for the rudder bellcrank. Since the FAA issued AD 2022- 19-03, the FAA determined that new or more restrictive tasks and limitations are necessary. This AD requires revising the ALS of the existing AMM or ICA for your airplane, as specified in a European Union Aviation Safety Agency (EASA) AD, which is incorporated by reference (IBR). The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12, PC-12/45, PC-12/ 47, and PC-12/47E airplanes. This AD is prompted by 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 identifies the unsafe condition as insufficient grounding of the vapor cycle cooling system (VCCS) compressor/condenser. This AD requires inspecting the power return and chassis grounding cable attachment points at frame 37, including the attachment parts, and depending on the inspection results, corrective action. This AD also requires modifying the installation of the VCCS compressor/condenser power return cables and installing an additional isolated VCCS chassis ground cable. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by 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 identifies the unsafe condition as corrosion of the actuator attachment lug areas underneath the anti-rotation pads of the main landing gear (MLG) and nose landing gear (NLG). This AD requires replacing certain MLG and NLG electro-mechanical actuators. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by 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 identifies the unsafe condition as a batch of incorrectly sized fuel transfer ejector nozzles that were installed on Model PC-12/47E airplanes during production. This AD requires removing the affected fuel transfer ejectors from service and prohibits installation of the affected fuel transfer ejectors. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by 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 identifies the unsafe condition as inward vent valves installed during production without chromate conversion coating on the bonding surface. This AD requires modifying the inward vent valves and prohibits installing unmodified inward vent valves. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. (Pilatus) Model PC-12/45, PC-12/47, and PC-12/47E airplanes with Supplemental Type Certificate (STC) SA00634DE installed. This AD was prompted by a report of strake attachment brackets and the fuselage frame failing at the upper most bracket attachment location. This AD requires inspecting the strake, attachment brackets, surrounding structure, and bolts and replacing components and repairing damage if necessary. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. (Pilatus) Model PC-12/47E airplanes. This AD was prompted by 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 inboard flap fairings aft (IFFAs) having an incorrect shape, which may result in chafing between the IFFA and the associated front inboard tension rod. This AD requires an inspection of the IFFAs for the correct shape and chafing between the IFFA and the associated front inboard tension rod, with corrective action as necessary. This condition could lead to failure of the inboard flap drive arm with consequent asymmetric flap extension, resulting in reduced control of the airplane. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. This AD was prompted by mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as improperly manufactured horizontal stabilizer rear attachment bolts. If not corrected, this could lead to fatigue failure of the bolts and loss of airplane control. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

The FAA is adopting a new airworthiness directive (AD) for Pilatus Aircraft Ltd. Model PC-12/47E airplanes. This AD was 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 seizing of a main landing gear (MLG) spring pack assembly. This AD requires replacement of affected parts and prohibits (re)installation of affected parts. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Model PC-12/47E airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 an error within the flight management system caused by installing Primus APEX software Build 10 or 10.9, which could cause deviation from the correctly calculated barometric vertical navigation nominal glide path. We are issuing this AD to require actions to address the unsafe condition on these products.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes installed with an affected engine mounting frame assembly. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 longitudinal material separation on the internal surface of the engine mounting frame assembly tubes. We are issuing this AD to detect and correct this condition, which could lead to partial or complete failure of the structural joint and possibly result in in-flight detachment of the engine with consequent loss of control.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 incorrect installation instructions of the torlon plates in the airplane maintenance manual resulting in the incorrect installation of the torlon plates in the forward wing-to-fuselage attachment. We are issuing this AD to require actions to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45, and PC-12/47E airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 a malfunction of the universal joint. We are issuing this AD to require actions to address the unsafe condition on these products.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Model PC-12/47 and PC-12/47E airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 the aileron trim tab disconnecting above 10,000 feet altitude. We are issuing this AD to require actions to address the unsafe condition on these products.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Airplanes

We are adopting a new airworthiness directive (AD) for PILATUS AIRCRAFT LTD. Model PC-12/47E airplanes. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 common grounding of both the pilot primary flight display (PFD) and the Electronic Standby Instrument System (ESIS). If the common ground fails both navigations systems could fail simultaneously, which could result in loss of control. We are issuing this AD to require actions to address the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-12/47E Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

Airworthiness Directives; Honeywell International Inc., Primus EPIC and Primus APEX Flight Management Systems, Installed on, but not Limited to, Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model ERJ 170 and ERJ 190 Airplanes, and Pilatus Aircraft Ltd. Model PC-12/47E Airplanes

We are adopting a new airworthiness directive (AD) for certain Honeywell International Inc., Primus EPIC and Primus APEX flight management systems (FMS), as installed on the airplanes described above. This AD requires revising the Limitations section of the airplane flight manual to incorporate the procedures necessary to recover from or work around a software anomaly in the FMS. This AD results from discovery of software anomalies which, in certain situations, can cause the FMS to generate misleading navigational guidance to the pilots and to the autopilot system of various airplanes having this same system software. We are issuing this AD to provide the flightcrew with procedures to recover from or work around these software anomalies during flight, which could lead to an airplane departing from its scheduled flight path, and result in possible collision with other aircraft or terrain.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Model PC-12/47E Airplanes

We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E Airplanes

We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI (two different MCAI) describes the unsafe condition as:

Airworthiness Directives; PILATUS AIRCRAFT LTD. Models PC-12 and PC-12/45 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-12/47E Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above that will supersede an existing AD. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Airworthiness Directives; PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45, PC-12/47, and PC-12/47E Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above that will supersede an existing AD. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Airworthiness Directives; PILATUS AIRCRAFT LTD. Model PC-12/47E Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Airworthiness Directives; PILATUS AIRCRAFT LTD. Model PC-12, PC-12/45, and PC-12/47 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. This AD requires inserting changes into the airworthiness limitations of the FAA-approved maintenance program. We are issuing this AD to require actions to correct the unsafe condition on these products.

Airworthiness Directives; PILATUS AIRCRAFT LTD. Models PC-12, PC-12/45, and PC-12/47 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Airworthiness Directives; Pilatus Aircraft Limited Model PC-12, PC-12/45, and PC-12/47 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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:

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12, PC-12/45, and PC-12/47 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above that will supersede an existing AD. This AD results from mandatory continuing airworthiness information (MCAI) issued by the aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Airworthiness Directives; Pilatus Aircraft Limited PC-12 and PC-12/45 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued 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 executive seats equipped with pedestal legs that were produced using a material that deviates from the approved design data. We are issuing this AD to require actions to correct the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an airworthiness authority of another country to identify and correct an unsafe condition on an aviation product. We are issuing this AD to require actions to correct the unsafe condition on these products.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

We are adopting a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 airplanes equipped with certain crew seat bucket assemblies with and without a backrest recline system. This AD requires you to replace the backrest tubes on these crew seat bucket assemblies at a specified time and adds a life limit for these backrest tubes. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to prevent cracks in the backrest tubes of certain crew seat bucket assemblies, which could result in failure of the seat system. This failure could lead to the pilot and co-pilot's reduced ability to control the airplane. This failure could also affect the proper function of the seat restrain system in the case of an emergency landing.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to inspect the left and right main landing gear (MLG) assemblies for any part number (P/N) 532.10.12.077 or FAA- approved equivalent part number bolts that do not have white primed and painted heads; and replace any bolt found with new P/N 532.10.12.077F or FAA-approved equivalent part number bolts in all MLG assemblies. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and correct any P/N 532.10.12.077 or FAA- approved equivalent part number bolts that do not have white primed and painted heads, which could result in corrosion of the bolt and consequent failure of the bolt. This failure could lead to MLG collapse during airplane landing and take-off operations with consequent loss of airplane control.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to determine (maintenance records check and/or inspection) whether certain nose landing gear (NLG), main landing gear (MLG), and MLG shock absorber assemblies with a serial number beginning with "AM" are installed, and, if installed, would require you to replace them with ones without the "AM." This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and correct the NLG, MLG, and MLG shock absorber assemblies that are affected by hydrogen embrittlement, which could result in failure of the landing gear. This failure could lead to nose or main landing gear collapse during operation with consequent loss of airplane control.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to insert a temporary revision into the Limitations Section of the Pilot Operating Handbook (POH). This AD also requires you to replace the pitch actuator with an improved design pitch actuator and make the necessary wiring and circuit breaker changes, as applicable. Installing the improved design pitch actuator terminates the need for the temporary revision in the POH. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to prevent an out-of-trim condition from occurring when the flaps are at a 40-degree flight phase and the pilot disconnects the autopilot. This condition could lead to reduced ability to control the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 airplanes. This AD requires you to do a one-time inspection of the windshield de-ice wiring system for heat damage and incorrect wire sizes and to replace any wires that are damaged or the incorrect size. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and replace windshield de-ice wiring of the incorrect size, which could result in heat damage of the windshield de-ice wiring. This failure could lead to possible fire in the overhead panel of the flight compartment.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to check the airplane logbook to determine whether any main landing gear (MLG) actuator (part number (P/N) 960.30.01.103) with serial numbers (SNs) 830E through 881E is installed. If any MLG actuator with one of these SNs is installed, you are required to replace the MLG actuator with a P/N 960.30.01.103 actuator that has a SN other than 830E through 881E. The pilot is allowed to do the logbook check. If the pilot can positively determine that no MLG actuator with one of these SNs is installed, then no further action is required. This AD results from mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to prevent failure of the MLG actuator caused by an incorrect heat treating process, which could result in loss of hydraulic extension/retraction of the MLG. This failure could lead to loss of control during ground operations.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to check the airplane logbook to determine whether certain inboard and outboard flap flexshafts have been replaced with parts of improved design. If the parts of improved design are not installed, you are required to replace certain inboard and/or outboard flap flexshafts with the parts of improved design. The pilot is allowed to do the logbook check. If the pilot can positively determine that the parts of improved design are installed, no further action is required. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to prevent rupture of the flap flexshafts due to corrosion, which could cause the flap system to become inoperable.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) for all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to determine whether certain main landing gear shock absorber attachment bolts have been replaced and, if not replaced, would require you to replace shock absorber attachment bolts on main landing gear assemblies that have a serial number beginning with AM001 through AM053. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and correct hydrogen embrittlement in the main landing gear shock absorber attachment bolts, which could result in failure of the main landing gear. This failure could lead to main landing gear collapse during operation with consequent loss of airplane control.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-7, PC-12, and PC-12/45 Airplanes

The FAA adopts a new airworthiness directive (AD) that supersedes AD 2002-01-09, which applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-7, PC-12, and PC-12/45 airplanes that incorporate a certain engine-driven pump. AD 2002-01-09 currently requires you to inspect the joints between the engine-driven pump housing, the relief valve housing, and the relief valve cover for signs of fuel leakage and extruding gasket material; replace any engine-driven pump with any of the above problems; and ensure that the relief valve attachment screws are adequately torqued and re-torque as necessary. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. This AD retains the actions from AD 2002-01- 09, adds certain engine-driven pumps to the applicability, and requires eventual replacement of the pump with an improved design pump to assure that the unsafe condition does not recur. We are issuing this AD to detect and correct gasket material extruding from the engine-driven pump housing and detect and correct relief valve attachment screws with inadequate torque. These conditions could lead to fuel leakage and result in a fire in the engine compartment.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires you to inspect for certain installed fuel booster pumps and replace that fuel booster pump, inspect other certain fuel booster pumps for defects, and either install lead protection spiral wrap or replace the defective fuel booster pumps, depending on whether defects are found. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. We are issuing this AD to detect and correct any defective fuel booster pump, which could result in electrical arcing from the leads in an air/fuel mixture. Such failure could lead to a fire or explosion of a fuel tank.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/ 45 airplanes. This AD requires you to repetitively replace the nose landing gear (NLG) drag link right-hand part every 4,000 landings until an improved design NLG drag link right-hand part is installed. This AD also requires you to install an improved design NLG drag link right- hand part as terminating action for the repetitive replacements. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent structural failure of the nose landing gear (NLG) caused by fatigue damage to the NLG drag link right-hand part that develops over time. Such failure could result in either an unintended NLG extension during flight or the NLG not properly locking upon extension, which could lead to loss of airplane control during landing operations.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires you to inspect the front and rear surfaces of the pressure dome for damage and cracks, and, if necessary, accomplish repairs. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to detect and correct damage and cracks to the pressure dome, which could lead to rapid decompression.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires you to inspect the pedestal leg assembly on aft facing passenger seats for correct configuration. If incorrectly configured, this AD requires you to modify to the correct configuration. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to detect and correct pedestal leg assemblies on aft facing passenger seats that are in nonconformance with manufacturing standards. Nonconforming passenger seats could result in passenger injury in an emergency situation.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires you to replace certain push switch caps on the electrical power management overhead panel with parts of improved design. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the inability to operate the switch, which could result in failure to activate the related operational system. Such failure could adversely affect the operation and control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/ 45 airplanes. This AD requires you to inspect the left and right main landing gear (MLG) assemblies for bolts with a serial number (S/N) beginning with the letters "AT" and numbers 299 or lower and replace each bolt with a bolt that does not have a S/N with both the letters "AT" and a number of 299 or lower. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to detect and replace defective MLG assembly bolts that have an improper cadmium plating, which could cause hydrogen embrittlement and bolt failure. Such failure could lead to MLG collapse during landing.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires you to replace the metered connector and oxygen tubing and related components in the rear seat bench. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to correct the potential for insufficient oxygen quantity that is available to occupants of the rear seat bench in some emergency conditions. This condition could result in reduced occupant safety at the rear bench seat location.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that supersedes Airworthiness Directive (AD) 99-19-32, which applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. AD 99-19-32 currently requires you to inspect the flap actuator internal gear system for correct end-play and backlash measurements and accomplish any corrective adjustments, as necessary. Pilatus has identified modifications for the flap system and designed and manufactured a new flap control and warning unit (FCWU) that permits the flap power drive-unit circuit breaker to close during flight. This AD requires you to modify the flap control wiring and install a flap power drive-unit field control panel. The actions specified by this AD are intended to allow the flap power drive-unit circuit breaker to close during flight and prevent current surges in the flap control system. If the pilot cannot close the circuit breaker during flight, the flight control and warning unit (FCWU) would not sense a worn actuator. Current surges in the flap control system could decrease the electrical life of the flap power drive-unit motor contactor. Both conditions have the potential for flap system failure with consequent reduced or loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/ 45 airplanes. This AD requires you to inspect the cargo doors to identify front and rear end frames with plain lightening holes and install reinforcing plates on any frame with plain lightening holes. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent cracking at the edges of the unflanged lightening holes, which could result in major structural damage to the airplane. Such damage could result in possible loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft LTD Models PC-12 and PC-12/45 Airplanes

This amendment supersedes Airworthiness Directive (AD) 99-17- 08, which currently requires modifying the generator 2 excitation by removing certain diodes and installing a new 5-amp circuit breaker and suppression filter on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD is the result of the Federal Aviation Administration's determination that the A250 voltage spike suppression filter in the modification kit can cause the circuit breaker 235 to trip because of overload. In extreme circumstances, this can lead to overheating of wiring. This AD requires you to modify the generator 2 excitation by removing certain diodes and installing a new 5-amp circuit breaker and suppression filter of improved design in accordance with revised procedures. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent damage to electrical components if generator 2 is not switched off before engine shutdown and it overheats. This could result in loss of electrical power to certain critical airplane components.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes that are equipped with a certain windshield configuration. This AD requires you to incorporate pilot's operating handbook (POH) information that prohibits the operation of the windshield heating system in the "LIGHT" mode, and requires you to modify the windshield deicing system wiring and circuit breakers. You can remove the POH information after accomplishing the modification. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent loss of electrical power to the windshield deicing system due to operation in the "LIGHT" mode, which could result in icing of the windshield and loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires you to perform a one-time inspection for abrasion damage, distortion, and proper clearance of the torque oil-pressure tubes and py pressure pipe, and if necessary, adjust and replace these components. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to correct abrasive damage from rubbing pipes and consequent loss of engine oil.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This document adopts a new airworthiness directive (AD) that applies to all Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/ 45 airplanes that are equipped with pneumatic deicing boots. This AD requires you to revise the Airplane Flight Manual (AFM) to include requirements for activation of the airframe pneumatic deicing boots. This AD is the result of reports of in-flight incidents and an accident (on airplanes other than the affected Pilatus airplanes) that occurred in icing conditions where the airframe pneumatic deicing boots were not activated. The Pilatus Models PC-12 and PC-12/45 airplanes have a similar type design (as it relates to airframe pneumatic ice boots) to the incident and accident airplanes. The actions specified by this AD are intended to assure that flightcrews activate the pneumatic wing and tail deicing boots at the first signs of ice accumulation. This action will prevent reduced controllability of the aircraft due to adverse aerodynamic effects of ice adhering to the airplane prior to the first deicing cycle.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires replacing the stick pusher capstan and the stick pusher servo with parts of improved design. The AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent improper operation of the stick pusher system caused by the existing design configuration, which could result in loss of control of the airplane during a stall.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires modifying the flap inboard attachment fittings through the installation of a reinforcement angle bracket on the inside of the center web of both flap inner attachment fittings. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the potential of the inboard flap attachment fittings buckling while operating at full flaps with full power into a head-on wind gust, which could result in loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires modifying the generator 2 excitation by removing certain diodes and installing a new 5-amp circuit breaker and suppression filter. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent damage to electrical components if the generator 2 is not switched off prior to engine shutdown and it overheats, which could result in loss of electrical power to certain critical airplane components.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires replacing all flap drive shafts with flap drive shafts of improved design, installing additional gaskets on the power drive unit, and modifying the attachment and supporting hardware. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the flap drive shafts from corroding to the point where the flexible shafts in the flap drive system rupture, which could result in the inability to utilize the flap system with reduced airplane control.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This action confirms the effective date of Airworthiness Directive (AD) 99-06-17, which applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. AD 99-06-17 requires installing a support bracket and a cut-out relay for the second generator control unit. AD 99-06-17 also requires making all the wiring additions and adjustments necessary for the above-referenced installations. This AD was the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to prevent damage to electrical components because incorrectly connected cables or broken or damaged wires cause excessive voltages to the second generator, which could result in loss of electrical power during any phase of flight.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires installing a support bracket and a cut-out relay for the second generator control unit. This AD also requires making all the wiring additions and adjustments necessary for the above-referenced installations. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to prevent damage to electrical components because incorrectly connected cables or broken or damaged wires cause excessive voltages to the second generator, which could result in loss of electrical power during any phase of flight.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires removing the ``Alternate Flap System'' from the airplane flight controls and inserting a temporary revision that specifies this change in SECTION 2--LIMITATIONS of the PC-12 Pilot's Operating Handbook. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to preclude improper use of the ``Alternate Flap System'', which could result in flap asymmetry with consequent reduced or loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes that are equipped with the ``corporate commuter cabin layout.'' This layout is a Pilatus designation only and the affected airplanes are not certificated for commuter operation. This AD requires modifying the passenger seats and seat rail covers. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent passenger injuries because the passenger seat configuration has been found to not fully meet current head injury criteria regulations.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 airplanes. This AD requires revising the FAA-approved Airplane Flight Manual (AFM) to specify procedures that would prohibit flight in severe icing conditions (as determined by certain visual cues), limit or prohibit the use of various flight control devices while in severe icing conditions, and provide the flight crew with recognition cues for, and procedures for exiting from, severe icing conditions. This AD is prompted by the results of a review of the requirements for certification of these airplanes in icing conditions, new information on the icing environment, and icing data provided currently to the flight crew. The actions specified by this AD are intended to minimize the potential hazards associated with operating these airplanes in severe icing conditions by providing more clearly defined procedures and limitations associated with such conditions.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment revises Airworthiness Directive (AD) 98-11-01, which currently requires replacing the fuel tank vent valves and drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. AD 98-11-01 also requires inserting a temporary revision in the Pilot's Operating Handbook (POH) that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects. This AD maintains the requirements of AD 98-11-01, and adds the option of modifying the fuel tank vent valves instead of the drilling and POH requirements carried over from AD 98-11-01. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to continue to prevent moisture from entering the fuel tank inward vent valve and then freezing after a cold soak at altitude, which could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-12 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12 airplanes. This AD requires replacing and re-routing the power return cables on the starter generator and generator 2, inserting a temporary revision to the pilot operating handbook (POH), and installing a placard near the standby magnetic compass. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent directional deviation on the standby magnetic compass caused by an overload of electrical current in the airplane structure, which could result in flight-path deviation during critical phases of flight in icing conditions and instrument meteorologic conditions (IMC).

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes that incorporate an executive cabin layout. This AD requires modifying the lavatory wall and passenger seat configuration. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent head injuries during an airplane crash because the lavatory wall and passenger seat configuration do not meet current head injury criteria regulations.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment supersedes Airworthiness Directive (AD) 97-23- 04, which currently requires replacing the fuel tank vent valves with modified fuel tank vent valves on certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD retains the fuel tank vent valves replacement required by AD 97-23-04, and requires drilling a 4.8 millimeter (0.1875 inch) hole in each fuel filler cap. This AD also requires inserting a temporary revision in the Pilot's Operating Handbook (POH) that specifies checking to assure that the fuel filler cap hole is clear of ice and foreign objects. This AD is the result of mandatory continued airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the fuel tank inward vent valve from freezing, which, if followed by a cold soak at altitude, could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-12 Airplanes

This action confirms the effective date of Airworthiness Directive (AD) 98-05-06, which applies to Pilatus Aircraft Ltd. (Pilatus) Model PC-12 airplanes. AD 98-05-06 requires inspecting the elevator for incorrect rivet lengths and installing new rivets if incorrect rivet lengths are found. This AD also requires inspecting the elevator to assure that an excessive gap (more than .004 inches or .1 millimeters (mm)) does not exist in the rivet shanks, and installing a shim between the rib and skin to fill any excessive gap. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to prevent fatigue damage to the elevator, which could result in structural failure and eventual loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires installing aluminum bonding bushings over certain screws in certain fuel tank underwing access panels. Several reports from the field revealing fuel tank access panels insufficiently electrically bonded to the airframe prompted this action. The actions specified by this AD are intended to prevent electrical arcing in the fuel tanks and detonation of the fuel-air mixture, which can be created by poor electrical bonding of fuel tank underwing access panels, and could result in a fire on the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires replacing certain propeller de-icing controllers with ones that are not susceptible to electromagnetic interference (EMI). This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent improper operation of the propeller de-icing controller caused by EMI, which could result in ice build-up on the propeller with possible airplane controllability problems.

Airworthiness Directives; Pilatus Aircraft Ltd. Model PC-12 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Model PC-12 airplanes. This AD requires inspecting the elevator for incorrect rivet lengths and installing new rivets if incorrect rivet lengths are found. This AD also requires inspecting the elevator to assure that an excessive gap (more than .004 inches or .1 millimeters (mm)) does not exist in the rivet shanks, and installing a shim between the rib and skin to fill any excessive gap. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified in this AD are intended to prevent fatigue damage to the elevator, which could result in structural failure and eventual loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC- 12/45 airplanes. This AD requires inspecting the aileron tie-rod jam nuts for looseness, tightening any loose jam nuts, and installing a locking sleeve on both ends of the aileron tie-rod in the chain-drive of the aileron system. The AD results from an incident where the aileron tie-rod jam nuts on the chain-drive of the aileron system became loose. This caused a differential of aileron control between the pilot's control wheel and the co-pilot's control wheel. The actions specified by this AD are intended to prevent such aileron control differential caused by the aileron tie-rod jam nuts becoming loose, which could result in loss of aileron control and consequent loss of control of the airplane.

Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to Pilatus Aircraft Ltd. (Pilatus) Models PC-12 and PC-12/45 airplanes. This AD requires replacing the fuel tank vent valves with modified fuel tank vent valves. This AD is the result of mandatory continued airworthiness information (MCAI) issued by the airworthiness authority for Switzerland. The actions specified by this AD are intended to prevent the fuel tank inward vent valve from freezing, which, if followed by a cold soak at altitude, could result in wing airfoil distortion and structural damage with consequent degradation of the airplane's handling qualities.

Airworthiness Directives; Pilatus Aircraft LTD Models PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4, and PC-12 Airplanes

This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft LTD (Pilatus) Models PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4 airplanes and all Pilatus Model PC-12 airplanes. This AD requires amending the Limitations Section of either the airplane flight manual (AFM) or the pilot's operating handbook (POH) to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight. This AFM amendment will include a statement of consequences if the limitation is not followed. This AD results from numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight. The actions specified by this AD are intended to prevent loss of airplane control or engine overspeed with consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.

Airworthiness Directives; LITEF GmbH Attitude Heading System (AHRS) Unit Model LCR-92, LCR-92S, and LCR-92H

This amendment adopts a new airworthiness directive (AD) that is applicable to LITEF GmbH Attitude and Heading Reference System (AHRS) Unit Model LCR-92, LCR-92S, and LCR-92H installed on but not limited to Sikorsky Aircraft Model S-76 helicopters, McDonnell Douglas Helicopter Systems Model MD-900 helicopters, Bell Helicopter Textron, Inc. Model 412 helicopters, and Pilatus Model PC-12 airplanes. This action requires either installing a placard adjacent to each primary attitude indicator which states that flight is limited to Visual Flight Rules (VFR) operations only, or modifying and inspecting the AHRS wiring cables, requiring a repetitive inspection of the cable shielding, and inserting a statement into the aircraft flight manual. This amendment is prompted by a field report and verified by laboratory tests that shows there is an unusual AHRS reaction to certain radio frequency signals. The actions specified by this AD are intended to prevent reliance on or to correct the cause of misleading roll and pitch information produced by the AHRS when encountering certain radio frequency signals.