British Aerospace Jetstream 41

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

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:

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. That AD currently requires operators to determine the number of flight cycles accumulated on each component of the main landing gear (MLG) and the nose landing gear (NLG), and to replace each component that reaches its life limit with a serviceable component. The existing AD also requires operators to revise the Airworthiness Limitations (AWL) section of the Instructions for Continued Airworthiness (ICA) in the aircraft maintenance manual to reflect the new life limits for structurally significant items. This new AD requires a new revision of the AWL section of the ICA to incorporate revised life limits for structurally significant items, operational and functional tests of certain systems, and instructions to retain critical ignition source prevention features during configuration changes. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country. We are issuing this AD to prevent failure of certain structurally significant items, including the MLG and the NLG, which could result in reduced structural integrity of the airplane; and to prevent fuel vapor ignition sources, which could result in fuel tank explosion and consequent loss of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is superseding an existing airworthiness directive (AD) that applies to certain British Aerospace (Jetstream) Model 4100 series airplanes. The existing AD currently requires an eddy current conductivity test to measure the conductivity of the upper splice plate of the wing, and related investigative and corrective actions if necessary. This AD revises the applicability to include additional airplanes. This AD results from reports of exfoliation corrosion of the upper splice plate of the wing. We are issuing this AD to detect and correct such corrosion, which could result in reduced structural integrity of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. That AD currently requires repetitive tests for free movement of the capsule/bearing of the nose landing gear (NLG), and related investigative and corrective actions. This new AD requires a modified test for free movement of the capsule/bearing of the NLG at reduced repeat intervals, and replacement of the NLG assembly with a modified assembly. This AD results from additional reports of the NLG failing to extend fully on an airplane that had been inspected in accordance with AD 2004-14-07. We are issuing this AD to prevent failure of the NLG to extend fully, which could result in reduced controllability of the airplane during landing.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

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:

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

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:

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

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:

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires modifying the wiring of the starter-generator terminal block. This AD results from a report of total electrical failure just as the airplane landed. We are issuing this AD to prevent total electrical failure and consequent reduced controllability of the airplane.

Airworthiness Directives; McCauley Propeller Systems Five-Blade Propeller Assemblies

The FAA is adopting a new airworthiness directive (AD) for certain McCauley Propeller Systems propeller assemblies installed on BAE Systems (Operations) Limited Jetstream model 4100 series airplanes. This AD requires removing certain propeller hubs from service at new reduced life limits and eddy current inspections (ECIs) of the propeller hub. This AD results from three reports of cracked propeller hubs. We are issuing this AD to prevent cracked propeller hubs, which could cause failure of the propeller hub, blade separation, and loss of control of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is superseding an existing airworthiness directive (AD), which applies to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. That AD currently requires operators to determine the number of flight cycles accumulated on each component of the main landing gear (MLG) and the nose landing gear (NLG), and to replace each component that reaches its life limit with a serviceable component. The existing AD also requires operators to revise the Airworthiness Limitations section (ALS) of the Instructions for Continued Airworthiness in the aircraft maintenance manual to reflect the new life limits. This new AD requires revising the ALS to incorporate extended and more restrictive life limits for structurally significant items. This AD is prompted by engineering analysis of fleet operations which resulted in more restrictive life limits. We are issuing this AD to prevent failure of certain structurally significant items, including the MLG and the NLG, which could result in reduced structural integrity of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires repetitive detailed and specialized inspections to detect fatigue damage in the fuselage, replacement of certain bolt assemblies, and corrective actions if necessary. This AD results from a review of primary airframe fatigue test results and a Maintenance Steering Group 3 (MSG-3) analysis. We are issuing this AD to detect and correct fatigue damage of the fuselage, door, engine nacelle, empennage, and wing structures, which could result in reduced structural integrity of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires the overhaul of certain auxiliary components installed on the main landing gear (MLG) and nose landing gear (NLG). This AD is prompted by manufacturer determination that overhaul limits need to be imposed for certain auxiliary components of the MLG and NLG. Components that exceed the established overhaul limits could fail due to fatigue, wear, and age. We are issuing this AD to prevent failure of the MLG or NLG, and consequent damage to the airplane and injury to flightcrew and passengers.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires replacing the aileron trim chain with a new, improved aileron trim chain, and modifying the installation of the aileron trim chain. This AD is prompted by a report that the aileron trim cables were connected incorrectly on a correctly installed aileron trim chain. We are issuing this AD to prevent incorrect connection of the aileron trim cables, which could result in failure of the aileron trim system and consequent reduced controllability of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

The FAA is adopting a new airworthiness directive (AD) for all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires repetitive detailed inspections of the aft fuselage frames for any discrepancies, and any applicable corrective actions. This AD is prompted by reports of corrosion found on the aft fuselage frames due to the ingress of water or liquid. We are issuing this AD to detect and correct corrosion of the aft fuselage frames, which could result in reduced structural integrity of the fuselage.

Airworthiness Directives; McCauley Propeller Systems Five-Blade Propeller Assemblies

The FAA is adopting a new airworthiness directive (AD) for McCauley Propeller Systems propeller assemblies, part numbers (P/Ns) B5JFR36C1101/114GCA-0, C5JFR36C1102/L114GCA-0, B5JFR36C1103/114HCA-0, and C5JFR36C1104/L114HCA-0, installed on BAE Systems (Operations) Limited Jetstream Model 4100 series airplanes. This AD requires a one- time eddy-current inspection of the propeller hub for cracks, and if necessary, replacing the propeller assembly. This AD results from three reports of cracked hubs. We are issuing this AD to detect cracked hubs, which could cause failure of the propeller hub and loss of control of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires various inspections of the fuselage nose structure between stations 4 and 11, and corrective actions if necessary. This action is necessary to detect and correct fatigue cracking in the primary structure of the nose of the airplane at the forward avionics bay (fuselage stations 4 to 11), which could result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires a test for free movement of the capsule/ bearing of the nose landing gear (NLG), and related investigative, significant, and corrective actions. This action is necessary to prevent failure of the NLG to extend fully, which could result in reduced controllability of the airplane during landing. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires a one-time inspection of the ailerons to determine if certain actions were accomplished previously, and related investigative and corrective actions if necessary. This action is necessary to prevent damage to the rear spar rib-to-rib attachment cleats and the aft rib elements of the fixed tabs of the ailerons. Such damage could lead to reduced structural integrity and consequent failure of the ailerons, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires operators to determine the flight cycles accumulated on each component of the main landing gear (MLG) and the nose landing gear (NLG), and to replace each component that reaches its life limit with a serviceable component. This AD also requires operators to revise the Airworthiness Limitations section of the Instructions for Continued Airworthiness in the aircraft maintenance manual to reflect the new life limits. This action is necessary to prevent failure of certain components of the MLG and the NLG, which could result in failure of either or both landing gears, and consequent damage to the airplane and injury to passengers or crewmembers. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires repetitively inspecting the seat rails located in the passenger cabin for evidence of damage and corrosion, repairing any damage or corrosion, and replacing any floor panels found to be "soft" due to ingress of moisture. This action is necessary to detect and correct corrosion on the seat rails for the passenger seats, which could result in the reduced structural integrity of the passenger seats, detachment of the seats from the seat rails, and injury to passengers. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires a review of airplane maintenance records and an inspection of the nose landing gear (NLG) to determine the part number of the steering pinion, and follow-on/corrective actions as applicable. This action is necessary to prevent failure of the steering pinion in the NLG, which could result in loss of steering and possible damage to the airplane during takeoff and landing. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires repetitive inspections for damage of the horizontal and vertical stabilizer attachment fittings, and corrective action if necessary. This action is necessary to detect and correct damage of the horizontal and vertical stabilizer attachment fittings, which could result in reduced structural integrity of the horizontal and vertical stabilizers and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes. This AD requires repetitive inspections for cracking in the casing of the nose landing gear (NLG), and corrective action if necessary. This action is necessary to find and fix cracking of the NLG casing, which could result in failure of the NLG, and consequent reduced controllability of the airplane during takeoff and landing. This action is intended to address the identified unsafe condition.

Airworthiness Directives; McCauley Propeller Systems, Inc. Propeller Hub Models B5JFR36C1101, C5JFR36C1102, B5JFR36C1103, and C5JFR36C1104

The FAA is superseding an existing airworthiness directive (AD) for McCauley Systems, Inc. propellers that are installed on, but not limited to, BAE Systems (Operations) Limited Jetstream Model 4101 airplanes. That AD currently requires a one-time fluorescent penetrant inspection (FPI) of propeller blade retention areas for cracks. This AD requires initial and repetitive FPI or Ultrasonic Inspection (UT) of propeller blade retention areas for cracks, replacement of high time propeller blades, and a one-time inspection of propeller hubs. This AD is prompted by four reports of significant cracks found in propeller blade shanks since the issuance of AD 2003-15-01. We are issuing this AD to prevent propeller blade failure or hub failure due to cracking, which could result in failure of the propeller and loss of control of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires inspection of the drive trunnion pins for the main landing gear (MLG) doors to determine the part number of the pins and corrective action if necessary. The actions specified by this AD are intended to prevent failure of the MLG and consequent reduced controllability of the airplane during takeoff or landing.

Airworthiness Directives; McCauley Propeller Systems, Inc. Propeller Hub Models B5JFR36C1101, C5JFR36C1102, B5JFR36C1103, and C5JFR36C1104

The FAA is adopting a new airworthiness directive (AD) for certain McCauley Systems, Inc. propellers that are installed on BAE Systems (Operations) Limited Jetstream Model 4101 airplanes. This AD requires a fluorescent penetrant inspection (FPI) of the propeller blades for cracks. This AD is prompted by a report of a significant crack in a propeller blade shank and two reports of cracks in the hubs of the same propeller model. We are issuing this AD to detect cracks in the propeller blade shank that could cause a failure of the propeller blade and loss of control of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires a functional test of the shortening mechanism of the nose landing gear for free movement of the capsule in the upper and lower bearings, and corrective action, if necessary. This action is necessary to prevent damage to the capsule, which could result in inability to extend the nose landing gear in normal or emergency situations, and consequent injury to passengers and flight crew. This action is intended to address the identified unsafe condition.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that currently requires repetitive inspections to detect loose or migrated levers of the elevator cable tension regulators, and replacement of the regulator assembly with a new assembly, if necessary. This amendment requires modification of the elevator cable tension regulator lever assembly, terminating the repetitive inspections. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent the elevator cable tension regulator from becoming detached from the splined shaft of the assembly, which could result result in difficulty adjusting the elevators, leading to reduced controllability of the airplane.

Airworthiness Directives; BAE Systems (Operations) Limited (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all BAE Systems (Operations) Limited (Jetstream) Model 4101 airplanes, that requires inspection for cracking of the mounting brackets of the hydraulic hand pump at the frame attachment flanges, replacement of any cracked bracket with a new bracket, replacement of all bolts and nuts with new bolts and nuts, and installation of a particular "D" packer. The actions specified by this AD are intended to prevent failure of these brackets, which could result in inability to extend the landing gear in an emergency situation where the main hydraulic system is lost. This action is intended to address the identified unsafe condition.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires revising the Airworthiness Limitations Section of the Instructions for Continued Airworthiness to incorporate life limits for certain items and inspections to detect fatigue cracking in certain structures. This amendment is prompted by issuance of a revision to the airworthiness limitations of the British Aerospace J41 Aircraft Maintenance Manual. The actions specified by this AD are intended to ensure that fatigue cracking of certain structural elements is detected and corrected; such fatigue cracking could adversely affect the structural integrity of these airplanes.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires a functional check of the rudder pedals to ensure full and free movement at all rudder pedal positions, and modification of the forward rudder pedal boxes. The actions specified by this AD are intended to prevent restricted movement of the rudder pedals due to structural interference, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires inspection of certain components, and corrective action, if necessary. The actions specified by this AD are intended to prevent loosening of the locknut holding the main landing gear (MLG) piston to the ramrod, which could result in detachment of the MLG piston from the ramrod and loss of hydraulic control of the MLG. This action is intended to address the identified unsafe condition.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires manufacture and installation of a placard on the left- hand instrument panel in the cockpit to prohibit push-backs of the airplane while the engines are running. In lieu of accomplishing the placard installation, this amendment requires repetitive installation of a new tow bracket sub-assembly that has the serial number and date of installation vibro etched on it. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent fatigue failure of the towing bracket. Failure of the towing bracket could cause a towing vehicle to collide into the propeller while the airplane engines are running, and consequently, cause damage to the airplane, and injure ground personnel, flight crew, or passengers.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that currently requires repetitive detailed visual inspections to detect cracking or other damage of certain diaphragm support structures of the forward equipment compartment; and repair, if necessary. This amendment continues to require repetitive inspections, but also requires replacement of cracked or damaged diaphragm support structures with improved parts, which terminates the requirement for repetitive inspections. This amendment also adds airplanes to the applicability of the AD. This amendment is prompted by the development of improved diaphragms. The actions specified by this AD are intended to prevent failure of the two diaphragms that support the upper structure of the forward equipment compartment, which could accelerate fatigue damage in adjacent structure and result in reduced structural integrity of the airframe.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires repetitive inspections to detect loose or migrated levers of the elevator cable tension regulators, and replacement of the regulator assembly with a new assembly, if necessary. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to detect and correct loose or migrated regulator levers of the elevator cable tension regulators, which could result in reduced controllability of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires a one-time inspection of the bottom aft roller of the main baggage-bay door structure for cracking or damage to the sub-frame; repetitive operational tests to determine if the counter- balance motor functions properly; and corrective actions, if necessary. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent sub-frame damage, which, if left undetected, could cause rapid decompression of the airplane and consequent injury to passengers and crew.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires a one-time visual inspection of the conduit pipe for distortion or repairs, and replacement of the conduit pipe with a new pipe, if necessary. This amendment also requires replacement of the cable assemblies to the fuel standby pumps with new cable assemblies that have improved sheathing protection. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent electrical arcing due to damaged fuel standby pump cable assemblies and conduit pipes, which could create a possible ignition source, and consequent fire hazard.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that requires modification of the pulley assemblies of the elevator and rudder control cables on the rear pressure bulkhead. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the pulley assemblies of the elevator and rudder control cables in the event of an elevator or rudder control cable jam, which could result in reduced controllability of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 series airplanes, that requires repetitive inspections to detect damage of the structure associated with the engine nacelle fairing attached to the wing flaps, and repair of any damage found; drilling a new drain hole in each engine nacelle fairing; and applying a sealant to the gap between the wing flap and engine nacelle fairing. This amendment also requires correction of discrepancies, and modification of the wing flap structure, which terminates the repetitive inspections. This amendment is prompted by reports of fatigue cracks found in the structure that attaches the engine nacelle fairing to the wing flaps. The actions specified by this AD are intended to prevent such fatigue cracking, which could result in the partial or complete separation of the fairing from the wing flap, and consequent additional structural damage to the airframe and/or reduced controllability of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that currently requires repetitive detailed visual inspections to detect cracks in the shear cleats of the roller guide structural support of the passenger door, and replacement of any cracked shear cleat with a new shear cleat. That AD also provides for an optional terminating modification that constitutes terminating action for the repetitive inspections. This amendment mandates accomplishment of the previously optional terminating modification. This amendment is prompted by reports indicating that fatigue cracking was detected in the roller guide shear cleats of the passenger door. The actions specified by this AD are intended to prevent such fatigue-related cracking, which could result in structural failure or loss of the passenger door, and consequent rapid depressurization of the airplane during flight.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires repetitive detailed visual inspections to detect cracking or other damage of certain diaphragm support structures of the forward equipment compartment; and repair, if necessary. This amendment is prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to detect and correct failure of the two diaphragms that support the upper structure of the forward equipment compartment, which could accelerate fatigue damage in adjacent structure and result in reduced structural integrity of the airframe.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires replacement of the existing load limitation labels located in the main baggage compartment with new reduced load limitation labels. This amendment also provides for optional modification of the internal access door of the main baggage compartment, which, if accomplished, terminates the requirement for reduced load limitations. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent failure of the internal access door latches of the main baggage compartment in the event of an emergency landing, which could delay or impede passenger evacuation due to baggage spilling into the aisle and blocking the emergency exit door.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to all British Aerospace (Jetstream) Model 4101 airplanes, that currently requires repetitive functional testing of the main entrance door, cleaning and lubricating of the ``speed'' lock and ``G'' lock systems, and repair, if necessary. This amendment adds a requirement for replacement of the ``G'' lock rollers with new, improved ``G'' lock rollers. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent inability of the main entrance door to open, which could delay or impede passengers from exiting the airplane, or rescue personnel from entering the airplane during an emergency.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that currently requires an inspection to determine the data on the label of certain hose assemblies, and replacement of all hose assemblies from any discrepant batch with certain new hose assemblies. This amendment requires a one-time inspection for different data on the label of certain hose assemblies, and replacement of all hose assemblies from any discrepant batch with certain new hose assemblies. This action also adds airplanes to the applicability of the existing AD. This amendment is prompted by a report of the failure of a hose assembly in the fire extinguisher system of the engine nacelle due to cracks, caused during manufacture of the hose assemblies, in the swaged ferrule that attaches the hose to the end fitting. The actions specified by this AD are intended to prevent failure of hose assemblies, which could prevent the proper distribution of fire extinguishing agent within the engine nacelle in the event of a fire.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires modification of the attach points of the uplock system of the nose landing gear (NLG). This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent wear of the attach points of the uplock system of the NLG; such wear could result in damage to the adjacent emergency hydraulic system, or jamming of the uplock system and consequent inability to extend and retract the NLG.

Airworthiness Directives; British Aerospace (Jetstream) Model 4100 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4100 series airplanes, that requires an eddy current conductivity test to measure the conductivity of the upper splice plate of the wing, and follow-on actions, if necessary. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to correct corrosion of the upper splice plate of the wing, which could result in reduced structural integrity of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires installation of a warning placard for the fire extinguisher exhaust port located in the rear baggage bay. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent blockage of the fire extinguisher exhaust port, which could result in reduced fire protection in the rear baggage bay and consequent injury to the passengers and crewmembers.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires replacement of certain wheel tie bolts with new bolts; and placing a life limit on these wheel tie bolts. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent metal fatigue failure of the wheel tie bolts, which could result in a tire burst or loss of the main wheel/tire assembly, and consequent reduced controllability of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires a one-time inspection for corrosion of electrical connectors in certain areas on the pressure bulkhead and rear baggage bay areas, and repair, if necessary; and installation of improved sealing. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent the accumulation of moisture inside the electrical connectors, which could result in a short circuit and consequent autopilot disconnect, or a latent failure of the stick pusher system.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires replacement of the stringer joint pieces at the left side of the fuselage with new, improved parts. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent the fuselage structure at the stringer joint at station 130 on the left side of the airplane from cracking, which could result in rapid decompression of the airplane at the forward fuselage area.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment revises an existing airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that currently requires an inspection to determine the thickness of the intercostal that attaches the third crew member seat to the floor structure in the flight compartment, and replacement, if necessary. That action was prompted by a report from the manufacturer indicating that intercostals have been installed that are not of sufficient thickness (and consequent strength) to support the third crew member seat during emergency landing dynamic conditions. The actions specified by that AD are intended to prevent the failure of this intercostal during an emergency landing, which could consequently result in injury to the flight crew. This amendment revises the applicability of the existing AD by removing several airplanes.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain British Aerospace (Jetstream) Model 4101 airplanes, that requires a one-time inspection of the tailplane (horizontal stabilizer) leading edges and surrounding area for discrepancies, and corrective action, if necessary. This amendment is prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent separation of the horizontal stabilizer from the fin, which could lead to reduced controllability of the airplane.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to all British Aerospace (Jetstream) Model 4101 airplanes. This action requires repetitive functional testing of the main entrance door, cleaning and lubricating of the ``speed'' lock and ``G'' lock systems, and repair, if necessary. This amendment is prompted by reports of flight crews and ground crews being unable to open the main entrance door. The actions specified in this AD are intended to prevent inability of the main entrance door to open, which could delay or impede passengers exiting the airplane, or rescue personnel from entering the airplane during an emergency.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain British Aerospace (Jetstream) Model 4101 airplanes. This action requires a visual inspection to detect wear damage of the drag brace of the main landing gear (MLG), and replacement of any worn parts with new or serviceable parts. This action also requires an inspection to determine whether there is movement in the spherical bearing of the lower link of the drag brace, certain measurements of the drag brace, and repetitive inspections, if necessary. This amendment is prompted by reports of loose spherical bearings in the links of the drag brace of the MLG. The actions specified in this AD are intended to prevent reduced structural integrity and potential collapse of the MLG due to loose spherical bearings and subsequent wear damage of the links of the drag brace.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain British Aerospace (Jetstream) Model 4101 airplanes. This action requires repetitive detailed visual inspections to detect cracks of the shear cleats of the roller guide structural support of the passenger door, and replacement of any cracked shear cleat with a new shear cleat. This action also provides for an optional terminating modification that constitutes terminating action for the repetitive inspections. This amendment is prompted by a report indicating that fatigue cracking was found in the roller guide shear cleats of the passenger door. The actions specified in this AD are intended to detect and correct such fatigue-related cracking, which could result in structural failure of the passenger door, and consequent rapid depressurization of the airplane or loss of the passenger door while the airplane is in flight.

Airworthiness Directives; British Aerospace (Jetstream) Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain British Aerospace (Jetstream) Model 4101 airplanes. This action requires an inspection to determine the data on the label of certain hose assemblies, and replacement of all hose assemblies from any discrepant batch with certain new hose assemblies. This amendment is prompted by a report of failure of a hose assembly in the fire extinguisher system of the engine nacelle due to cracks, caused during manfacture of the hose assemblies, in the swaged ferrule that attaches the hose to the end fitting. The actions specified in this AD are intended to ensure that such discrepant hose assemblies are replaced. Discrepant hose assemblies could fail and consequently prevent the proper distribution of fire extinguishing agent within the engine nacelle in the event of a fire.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires an inspection to determine the thickness of the intercostal that attaches the third crew member seat to the floor structure in the flight compartment, and replacement, if necessary. This amendment is prompted by a report from the manufacturer indicating that intercostals have been installed that are not of sufficient thickness (and consequent strength) to support the third crew member seat during emergency landing dynamic conditions. The actions specified by this AD are intended to prevent the failure of this intercostal during an emergency landing, which could consequently result in injury to the flight crew.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires repetitive detailed visual inspections to detect cracks on frame 179 at the attachment bracket for the door restraint cable, and various follow-on actions. This amendment also requires installation of new doublers and stress pads on frame 179, which would terminate the repetitive inspections. This amendment is prompted by reports of cracks in frame 179 of the fuselage at the attachment bracket for the door restraint cable on in-service airplanes due to improper rigging of the door restraint system. The actions specified by this AD are intended to prevent such cracking, which could result in structural failure of the fuselage and consequent rapid decompression of the pressurized section of the fuselage.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires the replacement of weight limitation placards in the aft main baggage bay and in the aft right stowage compartment with new placards indicating lower maximum weight limits. It also requires a revision of the Airplane Flight Manual to delete references to the current higher weight limits for these areas. This amendment is prompted by a report indicating that existing weight limitations could result in failure of the front bulkhead of the aft main baggage bay and doors of the aft right stowage compartment during emergency dynamic landing conditions. The actions specified by this AD are intended to prevent such failure, which consequently could result in injury to passengers and flight crew, and hinder evacuation of the airplane through the exit adjacent to this bulkhead.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires a one-time inspection of the airplane records to determine the modification status of the elevator trim servo, and, if necessary, inspections to determine the serial number of the servo, and repetitive inspections for looseness or movement of the motor housing of the servo. This action also requires replacement of certain elevator trim servos with a serviceable assembly. This amendment is prompted by reports of the motor housing separating from the elevator trim servo and the consequent release of certain component parts, due to inadequate locking of screws that were installed during assembly of the servos. The actions specified in this AD are intended to prevent the motor housing of the elevator trim servo from separating and releasing component parts that could lodge in and jam the elevator controls, and result in reduced pitch control of the airplane.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires a one-time inspection for damage caused by arcing and overheating of the electrical ground posts (``earth posts'') and ground cables for the direct current (DC) power generation and propeller de-icing systems of the left and right engines; and repair and replacement, if necessary. This amendment also requires the eventual replacement of earth posts with new posts. This amendment is prompted by reports indicating that earth posts on some airplanes have failed due to overheating. The actions specified by this AD are intended to prevent potential consequences of overheating, such as failure of the DC power generation and propeller de-icing systems.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires repetitive inspections to detect cracking of the offset lightening hole on the drag brace of the left and right main landing gear (MLG); and replacement of these braces with braces having a centralized lightening hole. This replacement terminates the repetitive inspections This amendment is prompted by a report indicating that fatigue cracking was detected on the upper link of a drag brace. The actions specified by this AD are intended to prevent fatigue cracking of the drag braces of the MLG, which, if not corrected, could cause the MLG to fail and, consequently, result in reduced controllability of the airplane during takeoff, landing, and taxiing.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that currently requires, among other things, replacing certain yaw damper servos in the autopilot system, or rendering the servo inoperative. The actions specified by that AD are intended to prevent overheat failure of the Flight Control Computer (FCC), which could result in smoke in the flight deck that could inhibit the ability of the flightcrew to safely operate and land the airplane. This new amendment requires installation of circuit breakers on the avionics relay panel, which, when accomplished, constitutes terminating action for the previous requirements of the AD.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 series airplanes, that requires a high frequency eddy current inspection to detect cracks of the boundary angle and joint angle of the rear pressure bulkhead, and repair, if necessary. This amendment also requires modification of the rear pressure bulkhead of the fuselage. This amendment is prompted by a report of fatigue cracking in the rear pressure bulkhead of the fuselage. The actions specified by this AD are intended to prevent such fatigue cracking, which could result in reduced structural integrity of the fuselage and, consequently, lead to the rapid decompression of the pressurized area of the airplane.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires a one-time test to verify if the disconnect lock of the aileron disconnect control system functions properly, and follow-on actions, if necessary. This amendment is prompted by a report that a disconnect unit of the aileron control system was found to be jammed and unserviceable. The actions specified in this AD are intended to detect and correct such jamming, which could result in reduced controllability of the airplane.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires a one-time check of the left and right main landing gear leg assemblies to determine whether certain assemblies have been installed; and the replacement of certain discrepant retaining bolts on these assemblies with correctly manufactured bolts. This amendment is prompted by a report indicating that some of these retaining bolts have failed during the assembly and installation of a main landing gear unit, due to an incorrect process that was used during the manufacture of the bolts. The actions specified in this AD are intended to prevent structural damage to the main landing gear due to failure of the retaining bolts which, if not corrected, could result in reduced controllability of the airplane during takeoff, landing, and taxiing.

Airworthiness Directives; Jetstream Model 4100 Series Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4100 series airplanes, that requires replacement of the existing decompression panel on the aft bulkhead of the toilet compartment with a modified decompression panel. This amendment is prompted by a report that a decompression panel that does not meet flammability requirements was installed on these airplanes during manufacture. The actions specified by this AD are intended to prevent injury to the crew and passengers and damage to the airplane structure due to the incapability of the decompression panel to contain a fire.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that currently requires inspection to determine the number of hours time-in- service on the landing gear control unit, and modification of the cable (electrical wiring circuit) of the landing gear control unit. That AD was prompted by a report of failure of a micro-switch in the landing gear control unit. This amendment requires installation of a new landing gear control unit. This amendment also expands the applicability of the existing AD to include additional airplanes. The actions specified by this AD are intended to prevent uncommanded retraction of a landing gear, which could adversely affect airplane controllability.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires a one-time inspection of the airplane records to determine the serial number, the total number of hours time-in-service accumulated, and the date of installation of the yaw damper servo in the autopilot system; and to determine the date of installation of a particular kit, if installed. This action also requires removing and replacing the yaw damper servo, or rendering the yaw damper servo inoperative. This action also provides for optional terminating action for the requirements of this AD. This amendment is prompted by reports of smoke in the flight deck due to overheat failure of the Flight Control Computer (FCC). The actions specified in this AD are intended to prevent such overheat failure, which could result in smoke in the flight deck that could inhibit the ability of the flightcrew to safely operate and land the airplane.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires an inspection to determine the serial number of the leg assemblies of the main landing gear (MLG), and replacement of defective pins with serviceable pins. This amendment is prompted by a report indicating that pins installed on certain leg assemblies of the MLG's were heat treated incorrectly during manufacture. The actions specified in this AD are intended to prevent failure of the pins due to incorrect heat treatment, and subsequent structural failure of the MLG.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to all Jetstream Model 4101 airplanes. This action requires a review of maintenance records to determine the time-in-service (TIS) of the bearings in the starter/ generators of both engines. This action also establishes a new TIS limit for the bearings, and requires replacement of the starter/ generator unit with a serviceable unit, if necessary. This amendment is prompted by reports of controlled in-flight engine shutdowns resulting from failure of the bearings in the starter/generator unit. The actions specified in this AD are intended to prevent such failure of the bearings of the starter/generator, which could cause severe vibrations and resultant in-flight shutdown of one or both engines.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires modification of the existing diaphragms on the surround structure of the Type II emergency exit. This amendment is prompted by a report indicating that, during fatigue tests on a Model 4101 test article, fatigue-related cracking was found in the surround structure of a Type II emergency exit. The actions specified by this AD are intended to prevent such cracking in the surround structure, which could result in reduced structural integrity of the fuselage pressure vessel.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires replacement of the flexible cables of the power and condition controls of the engines with new flexible cables. This amendment also requires installation of protective tape on the outside case of these flexible cables, and reidentification of the cables. This amendment is prompted by reports of stiff operation of the power and condition controls of the engines due to heat damage to and moisture contamination of the flexible cable. The actions specified by this AD are intended to prevent heat damage and moisture contamination to the flexible cable, which could result in stiff operation of the power and condition controls and subsequent reduced engine control.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires inspections of the handrail assembly at the main entrance door to detect loose or missing rivets, abnormal movement between the handrail pivot-tube and the spigot that attaches to the bearing assembly, and cracks on the handrail pivot-tube. It also requires repair or replacement of the assembly, if necessary, and provides for two optional terminating actions. This amendment is prompted by a report indicating that fatigue cracks and loose rivets were found on the handrail assembly of the main passenger entrance door on an in-service airplane. The actions specified by this AD are intended to prevent these conditions, which can lead to the failure of the door handrail assembly; such failure could allow the door to fall free and subsequently cause injury to people on the airplane or on the ground.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to all Jetstream Model 4101 airplanes, that requires revising the Airplane Flight Manual (AFM) to provide the flight crew with recognition cues for, and procedures for exiting from, severe icing conditions, and to limit or prohibit the use of various flight control devices. This amendment is prompted by results of a review of the requirements for certification of the airplane in icing conditions, new information on the icing environment, and icing data provided currently to the flight crews. The actions specified by this AD are intended to prevent or minimize the potential hazards associated with operating the airplane in severe icing conditions by providing more clearly defined procedures and limitations associated with such conditions.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires an inspection to verify the proper position of ``door open'' placards on the inside of the main entrance door, and replacement with new placards appropriately positioned, if necessary. This amendment is prompted by a report that the ``door open'' placards on the inside of the main entrance door, as currently installed, may not be visible to passengers or flightcrew when the door handle is in the open position. The actions specified by this AD are intended to ensure that certain placards on the inside of the main entrance door are clearly visible and perform their intended function in the event of an emergency evacuation.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment revises an existing airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that currently requires repetitive inspections to detect damage to the overwing fairings, and replacement or repair of structurally damaged fairings. That AD was prompted by a report indicating that an overwing fairing detached from an airplane. The actions specified by that AD are intended to prevent reduced controllability of the airplane due to loss of an overwing fairing. This amendment adds an optional terminating action for the currently required inspections, and limits the applicability of the rule.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment supersedes an existing airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that currently requires repetitive purging of the hydraulic system and installation of a spoiler actuator that has been previously certified. That AD was prompted by a report of damage to the locking mechanisms on some pistons of the spoiler actuators. The actions specified by the AD are intended to prevent uncommanded extension of the lift spoiler in the event of loss of hydraulic pressure in the spoiler actuator. This amendment establishes an increased life limit for certain spoiler actuators, and provides an optional terminating action for the requirements of that AD. This amendment also limits the applicability of the rule to fewer airplanes.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Jetstream Model 4101 airplanes. This action requires a visual inspection of the passenger seat belt assemblies to determine if certain seat belt shackles are installed, and replacement of those shackles with improved ones. This amendment is prompted by reports indicating that certain passenger seat belt shackles have failed. The actions specified in this AD are intended to prevent reduced effectiveness of the passenger safety restraint system during take-off and landing or in an emergency situation, due to failure of the passenger seat belt shackles.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires an inspection to determine if a travel stop (screw) is installed at the flight control assembly, and various follow-on actions. This amendment is prompted by a report of failure of the travel stop, which allowed the elevator and aileron disconnect handles to rotate within the housing due to migration of the travel stop from its position. The actions specified by this AD are intended to prevent such migration, which could result in the elevator and aileron disconnect system resetting without the use of the reset button; this condition could lead to jamming of the disconnect handles.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment revises an existing airworthiness directive (AD), applicable to all Jetstream Model 4101 airplanes, that currently requires modification of the mounting structure of the elevator controls on the rear pressure bulkhead. That AD was prompted by results of a structural analysis which indicate that certain structure in the elevator control system may be subject to deformation when maximum load is exerted by the pilot(s) in the event of a jam in the elevator control cables. The actions specified in that AD are intended to prevent reduced controllability of the airplane due to structural deformation in the elevator control system. This amendment limits the applicability of the rule.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires replacement of a certain pressure switch with a certain new pressure switch in the fuel system for the engines. This amendment is prompted by a report indicating that the current design of a certain pressure switch in the fuel system for the engines does not meet current fire resistant properties, which could result in the failure of the pressure switch during a fire in the engine compartment. The actions specified by this AD are intended to prevent failure of the existing pressure switch in the fuel system for the engines, which, during an engine fire, could result in fuel leakage that could add fuel to the fire.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 95-09-03, that was sent previously to all known U.S. owners and operators of Jetstream Model 4101 airplanes by individual letters. This AD requires inspection to determine the number of hours time-in-service on the landing gear control unit, and modification of the cable (electrical wiring circuit) of the landing gear control unit. This amendment is prompted by a report of failure of a micro-switch in the landing gear control unit. The actions specified by this AD are intended to prevent uncommanded retraction of a landing gear, which could adversely affect airplane controllability.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires installation of new case drain pipes and an additional fairlead support for the hydraulics case drain line in the rear spar area of the engine/ nacelle. This amendment is prompted by reports of fatigue failure of the case drain line in the hydraulics system. The actions specified by the proposed AD are intended to prevent the loss of main system hydraulics as a result of lack of support against vibration and subsequent fatigue failure of the case drain line for the hydraulics system.

Airworthiness Directives; Jetstream Model 4101 Airplanes

This amendment adopts a new airworthiness directive (AD), applicable to certain Jetstream Model 4101 airplanes, that requires modification of the spoiler system. This amendment is prompted by reports of fatigue failures of the tee fittings of the spoiler bleed nipples. The actions specified by this AD are intended to ensure that the tee fittings do not fail, and subsequently lead to loss of the main system hydraulics.