Bell 427

Airworthiness Directives; Bell Textron Canada Limited Helicopters

The FAA is adopting a new airworthiness directive (AD) for certain Bell Textron Canada Limited (Bell) Model 427 helicopters. This AD was prompted by a report of a cracked transmission oil check valve (check valve). This AD requires inspecting and measuring certain check valves and, depending on the results, repetitively inspecting and removing the check valve from service if it has leaks or is cracked. This AD also prohibits installing the affected check valves on any helicopter. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Bell Textron Canada Limited Helicopters

The FAA is adopting a new airworthiness directive (AD) for all Bell Textron Canada Limited (BTCL) Model 407 and 427 helicopters. This AD was prompted by a report that certain expandable blade bolts installed on the main rotor blade may not have received the correct heat treatment, which could result in stress corrosion cracking of the expandable blade bolts. This AD requires removing the expandable blade bolts from service and replacing them with a part eligible for installation. This AD also prohibits the installation of an affected expandable blade bolt on any helicopter. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Bell Textron Canada Limited Helicopters

The FAA is adopting a new airworthiness directive (AD) for certain Bell Textron Canada Limited Model 206, 206A, 206A-1 (OH-58A), 206B, 206B-1, 206L, 206L-1, 206L-3, 206L-4, 222, 222B, 222U, 230, 407, 427, 429, and 430 helicopters. This AD was prompted by a report of a shoulder harness seat belt comfort clip (comfort clip) interfering with the seat belt inertia reel. This AD requires removing each comfort clip from service, inspecting the shoulder harness seat belt for any rip and abrasion, and removing any shoulder harness seat belt from service that has a rip or abrasion. The FAA is issuing this AD to address the unsafe condition on these products.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

The FAA is adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada Limited (BHTC) Model 427 helicopters. This AD requires inspecting the inboard skin of the vertical fin around the four tailboom attachment points. This AD was prompted by reports of cracked vertical fin skins that resulted from metal fatigue. The actions of this AD are intended to prevent an unsafe condition on these products.

Airworthiness Directives; Bell Helicopter Textron Canada Limited (Bell) Helicopters

We are adopting a new airworthiness directive (AD) for Bell Model 427 and Model 429 helicopters. This AD requires replacing certain engine and transmission oil check valves. This AD also prohibits installing the affected check valves on any helicopter. This AD is prompted by a report of several cracked or leaking check valves. These actions are intended to detect and prevent a cracked or leaking check valve which could result in loss of lubrication to the engine or transmission, failure of the engine or transmission, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Helicopters

We are superseding Airworthiness Directive (AD) 2001-13-51 for Bell Model 206L-4, 407, and 427 helicopters. AD 2001-13-51 required inspecting certain driveshafts for a crack, a loose bolt or nut, or red powder residue and replacing a driveshaft if there is a crack, a loose bolt or nut, or red powder residue. AD 2001-13-51 also required notifying the FAA within 10 days if a crack is found in the driveshaft. This new AD retains the inspection requirement of AD 2001-13-51, expands the applicability to include the Model 429 helicopter, and removes the reporting requirement. This AD is intended to prevent failure of a driveshaft, loss of drive to the main rotor system, and a subsequent emergency landing.

Airworthiness Directives; Bell Helicopter Textron Canada Limited (Bell) Helicopters

We are adopting a new airworthiness directive (AD) for Bell Model 206A, 206B, 206L, 206L-1, 206L-3, 206L-4, 222, 222B, 222U, 230, 407, 427, and 430 helicopters. This AD requires inspecting each bearing to determine if it has been properly staked and replacing the bearing or assembly if it has not been properly staked. This AD was prompted by bearings not being properly staked and migrating out of their proper position, which may limit the functionality of the affected part. The actions of this AD are intended to prevent failure of a bearing and the assembly in which it is installed and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Helicopters

We are adopting an airworthiness directive (AD) superseding an existing airworthiness directive for Bell Helicopter Textron Canada (Bell) Model 407 and 427 helicopters. The existing AD requires inspecting certain hydraulic servo actuators (servo) to determine whether the shaft turns independently of the nut or the clevis assembly, and additional actions based upon the inspection's outcome. The AD also requires reidentifying the servo. Since we issued that AD, Bell has learned that additional servos may need repair or removal. This AD expands the scope of the current AD to include inspections for all servos, and requires that servos meeting inspection requirements be marked with the letter "V" after the part number on the data plate. The actions are intended to detect any loose or misaligned parts in the servo that could lead to failure of the servo and subsequent loss of helicopter control.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

We are adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada Limited (BHTC) Model 427 helicopters which requires replacing certain tailboom attachment hardware and at certain intervals thereafter, determining the torque of that tailboom attachment hardware. This AD was prompted by a review of the tailboom attachment installation, which revealed that the torque value of the bolts specified in the BHTC Model 427 Maintenance Manual and applied during manufacturing was incorrect and exceeded the torque range recommended for the bolts. The actions are intended to prevent an over- torque of the tailboom attachment bolt (bolt), bolt failure, loss of the tailboom, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Model 407 and 427 Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2011-15-51, which was sent previously to all known U.S. owners and operators of the specified Bell Model 407 and 427 helicopters by individual letters. This AD requires inspecting certain hydraulic servo actuators to determine whether the shaft turns independently of the nut or the clevis assembly. If the shaft turns independently, this AD requires replacing the servo with an airworthy servo. If the shaft does not turn independently, the AD requires inspecting to determine the condition of the lock washers. Based on the condition of the lock washers, the AD requires either replacing the servo with an airworthy servo, or if any tab of the lock washer is not flush against a flat surface of the nut or clevis assembly, bending it flush against a flat surface. The AD also requires reidentifying the servo by metal-impression stamping or by vibro- etching "67.01" onto the modification plate. Also, the AD requires before installing a servo with a part number or serial number identified in this AD, not identified by "67-01" on the modification plate, inspecting it by following the requirements of this AD. This AD is prompted by a report that a quality escape by a supplier has occurred and certain servos may have a loose nut, shaft, and clevis assembly due to improper lock-washer installation. An investigation after an accident revealed the clevis nut on the servo was loose. The actions specified by this AD are intended to prevent a malfunction of a servo in the flight control system and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Limited (BHTC) Model 206A, 206B, 206L, 206L-1, 206L-3, 206L-4, 222, 222B, 222U, 230, 407, 427, and 430 Helicopters

This document publishes in the Federal Register an amendment adopting Emergency Airworthiness Directive (AD) 2010-26-51, which was sent previously to all known U.S. owners and operators of the specified model helicopters by individual letters. This AD also supersedes existing AD 2009-08-03. This AD is prompted by another incident in which the tail rotor blade (blade) tip weight separated from a blade during flight causing vibration. This unsafe condition led to the determination that additional blades could be affected and should be added to the applicability. The actions specified by this AD are intended to prevent loss of the blade tip weight, loss of a blade, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Model 427 Helicopters

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; Bell Helicopter Textron Canada (BHTC) Model 407 and Model 427 Helicopters

We are adopting a new airworthiness directive (AD) for the BHTC Model 407 and Model 427 helicopters. This AD results from mandatory continuing airworthiness information (MCAI) ADs issued by the aviation authority of Canada. The MCAI ADs state that some hydraulic pump driveshaft assemblies may have been delivered with a missing internal plug or fastening rivet. This condition, if not corrected, could result in a loss of hydraulic pressure and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Model 407 and 427 Helicopters

We are adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada (Bell) Model 407 and 427 helicopters. This AD results from a mandatory continuing airworthiness information (MCAI) AD issued by the aviation authority of Canada. The MCAI AD states that, during a preflight check, it was observed that the swashplate link assembly bearing had moved in the lever race, making contact with the swashplate support. The MCAI also states that further investigation revealed that the bearing had not been staked correctly during manufacture. That condition, if not detected, could result in failure of a bearing, failure of the swashplate link assembly, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Model 427 Helicopters

We are adopting a new airworthiness directive (AD) for Bell Helicopter Textron Canada (BHTC) Model 427 helicopters. This AD results from mandatory continuing airworthiness information (MCAI) originated by the aviation authority of Canada to identify and correct an unsafe condition on an aviation product. Transport Canada, the aviation authority of Canada, with which we have a bilateral agreement, states that it has been determined that the existing hardware connecting the vertical fin to the tail rotor gearbox needs to be upgraded to prevent the vertical fin from becoming loose. BHTC has received reports of loose vertical fins discovered during inspections. Investigation revealed that the current vertical fin attachment hardware may not provide adequate clamp-up. If not corrected, the vertical fin could become loose and cause vibration, which could lead to subsequent loss of control of the helicopter. This AD requires actions that are intended to address this unsafe condition.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Model 206A Series, 206B Series, 206L Series, 407, and 427 Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2009-07-52 and supersedes Emergency AD 2009-07-51, issued March 17, 2009, which was sent previously to all known U.S. owners and operators of Bell Helicopter Textron Canada Limited (Bell) Model 206A series, 206B series, 206L series, 407, and 427 helicopters by individual letters. This AD requires, before further flight, inspecting each cyclic control lever assembly (lever assembly) that has less than 50 hours time-in-service (TIS) to determine if it is correctly installed and properly staked in the lever assembly. This amendment is prompted by a Transport Canada AD report of a bearing incorrectly installed in the copilot lever assembly. The actions specified by this AD are intended to prevent failure of a bearing, failure of the lever assembly, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Model 206A, 206B, 206L, 206L-1, 206L-3, 206L-4, 222, 222B, 222U, 230, 407, 427, and 430 Helicopters

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2007-19-52, which was sent previously to all known U.S. owners and operators of the specified Bell Helicopter Textron Canada Limited (BHTC) model helicopters by individual letters. This AD requires replacing each affected tail rotor blade (blade) with an airworthy blade with a serial number not listed in the Rotor Blades, Inc. (RBI), attachment to the BHTC Alert Service Bulletin (ASB), listed in the applicability section of this AD. This amendment is prompted by three incidents in which blade tip weights were slung from blades during flight causing significant vibration. The actions specified are intended to prevent loss of a blade tip weight, loss of a blade, and subsequent loss of control of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada (Bell) Model 427 Helicopters

This amendment adopts a new airworthiness directive (AD) for the specified Bell model helicopters that requires replacing the hydraulic solenoid tee fitting (tee fitting) and tubes. This amendment is prompted by the manufacturer's discovery that tee fittings may be installed improperly and restrict hydraulic fluid flow. The actions specified by this AD are intended to prevent restricted flow of hydraulic fluid to the flight control hydraulic actuators resulting in loss of hydraulic control, excessive stiffness in the flight controls, and a subsequent forced landing of the helicopter.

Airworthiness Directives; Bell Helicopter Textron Canada Limited Model 427 Helicopters

This amendment adopts a new airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (Bell) model helicopters that requires modifying the auxiliary fin assemblies and revising the Limitations section of the Rotorcraft Flight Manual (RFM) to reduce the never-exceed speed (Vne) for a tail rotor pedal stop failure. This amendment is prompted by several incidents of main rotor blades contacting the top of the fin that have resulted in an upper tuning weight (weight) becoming loose. The actions specified by this AD are intended to prevent a main rotor blade from striking an auxiliary fin, loss of a tuning weight, impact with a tail or main rotor blade, and subsequent loss of control of the helicopter.