Results
91-07-12: 91-07-12 BRITISH AEROSPACE: Amendment 39-6950. Docket No. 90-NM-273-AD. Applicability: All Model DH/BH/HS 125 series airplanes, post-modification 255640, certificated in any category. Compliance is required as indicated, unless previously accomplished. To ensure proper operation of the main landing gear (MLG) door, accomplish the following: A. Prior to the accumulation of 6,000 landings on the right and left MLG door aluminum forward hinge fittings, or within the next 400 landings after December 4, 1990 (the effective date of Amendment 39-6786, AD 90-23-01), whichever occurs later, and thereafter at intervals not to exceed 6,000 landings, replace the aluminum forward hinge fittings in accordance with British Aerospace Service Bulletin 32-218, dated July 28, 1988. B. Replacement of an aluminum hinge fitting with a new stainless steel hinge fitting, in accordance with British Aerospace Service Bulletin 32-220-3176A, B, and C, dated September 2, 1988, terminates the requirements for the replacement of the hinge fittings required by paragraph A. of this AD. C. An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service information from the manufacturer may obtain copies upon request to British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041-0414. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. Airworthiness Directive 91-07-12 supersedes AD 90-23-01, Amendment 39-6786. This amendment (39-6950, AD 91-07-12) becomes effective on April 29, 1991.
2004-20-02: This amendment adopts a new airworthiness directive (AD), applicable to all Boeing Model 707 and 720 series airplanes, that requires an inspection of the main landing gear (MLG) lock support fitting and the wing fillet flap support link for damage, and corrective action, if necessary; and replacement of the bolts and bushings at the joint between the MLG lock support fitting and the wing fillet flap support link. This action is necessary to prevent stress corrosion cracking of the bolts and wearing of the joint between the lock support fitting and the support link, which could lead to failure of the joint and could cause the collapse of the MLG. This action is intended to address the identified unsafe condition.
2013-12-05: We are adopting a new airworthiness directive (AD) for Eurocopter Deutschland GmbH (Eurocopter) Model MBB-BK 117 C-2 helicopters. This AD requires determining if a certain serial-numbered bevel gear is installed in the tailrotor intermediate gear box (IGB). If such a bevel gear is installed in the IGB, this AD requires recording the bevel gear's reduced life limit in the Airworthiness Limitations section of the maintenance manual and on the component history card or equivalent IGB record. If the bevel gear's life limit has been reached or exceeded, this AD requires, before further flight, replacing the bevel gear with an airworthy bevel gear. This AD is prompted by the discovery that the tooth foot fillets in certain bevel gears fall below the minimum dimensions required in the design documents to ensure safe functioning of the bevel gear until it reaches its approved life limit. This AD's actions are intended to prevent failure of a bevel gear before it reaches its currentlyapproved life limit, failure of the IGB, and subsequent loss of helicopter control.
96-25-15: This amendment adopts a new airworthiness directive (AD), applicable to certain transport category airplanes equipped with certain Honeywell Standard Windshear Detection System (WSS). It requires a revision to the airplane flight manual to alert the flightcrew of the potential for significant delays in the WSS detecting windshear when the flaps of the airplane are in transition. This amendment also requires replacement of the currently-installed line replaceable unit (LRU) with a modified LRU having new software that eliminates delays in the WSS. This amendment is prompted by a report of an accident during which an airplane encountered severe windshear during a missed approach. The actions specified by this AD are intended to prevent significant delays in the WSS detecting hazardous windshear, which could lead to the loss of flight path control.
2022-18-16: The FAA is adopting a new airworthiness directive (AD) for all General Electric Company (GE) CT7-8A model turboshaft engines. This AD was prompted by the manufacturer revising the airworthiness limitations section (ALS) of the existing engine maintenance manual (EMM) to incorporate reduced life limits for certain stage 1 turbine aft cooling plates, stage 2 turbine forward cooling plates, turbine interstage seals, and stage 4 turbine disks. This AD requires revising the ALS of the existing EMM and the operator's existing approved maintenance or inspection program, as applicable, to incorporate reduced life limits for these parts. The FAA is issuing this AD to address the unsafe condition on these products.
91-06-18: 91-06-18 AIRBUS INDUSTRIE: Amendment 39-6940. Docket No. 90-NM-225-AD. Applicability: All Model A310-200 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To detect cracks in the wing rear spar and prevent reduced structural integrity of the wings, accomplish the following: A. Prior to the accumulation of 12,000 landings, or within 1,000 landings after the effective date of this AD, whichever occurs later, perform a high frequency eddy current (HFEC) rototest inspection of the wing rear spar at certain bolt holes where the main landing gear (MLG) forward pick-up fittings are attached to the rear spar, in accordance with Airbus Industrie Service Bulletin A310-57-2046, dated March 5, 1990. 1. If no cracks are found at the first inspection and no cold working of the holes concerned is carried out, repeat the HFEC rototest inspection at intervals not to exceed 4,500 landings. 2. If no cracksare found at the first inspection and a spar life extension by cold working of the holes concerned is carried out in accordance with the paragraph 2.3.(1)(b) of the Accomplishment Instructions of the above service bulletin or Airbus Industrie Service Bulletin A310-57-2049, dated April 10, 1990; repeat the HFEC rototest inspection within the next 18,000 landings, and thereafter at intervals not to exceed 12,000 landings. B. If cracks are found, repair prior to further flight, in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Repeat the HFEC rototest inspection at an interval approved by the Manager, Standardization Branch, ANM-113. C. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be submitted directly to theManager, Standardization Branch, ANM-113, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, Standardization Branch, ANM-113. D. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Airbus Industrie, Airbus Support Division, Avenue Didier Daurat, 31700 Blagnac, France. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6940, AD 91-06-18) becomes effective on April 22, 1991.
96-21-13: 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.
2004-20-03: This amendment adopts a new airworthiness directive (AD), applicable to all Bombardier Model DHC-8-101, -102, -103, -106, -201, - 202, -301, -311, and -315 airplanes. This amendment requires a detailed inspection of the wing leading edge de-icer boots to determine if they comply with certain patch limits in the critical zone; and corrective action, if necessary. This action is necessary to prevent reduced aerodynamic smoothness of the wing leading edge de-icer boots and possible reduced stall margin, which could result in a significant increase in stall speeds, leading to a possible stall prior to activation of the stall warning. This action is intended to address the identified unsafe condition.
76-12-01: 76-12-01 BELL: Amendment 39-2636. Applies to Bell Models 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, and 47H-1 helicopters certificated in all categories. Compliance required within 300 hours' time in service after the effective date of this AD unless already accomplished. To prevent possible fatigue failure of tail rotor hub bolt, Part Numbers 47-641-052-3 or - 5, accomplish the following: (a) Remove and disassemble the tail rotor hub and blade assembly. (b) Remove the metal grease seal from each tail rotor blade grip and install the seal, Part Number 47-641-042-3, in each blade grip to clear the head of the hub bolt. (c) Remove the hub assembly bolts, Part Numbers 47-641-052-3 or -5, from the tail rotor hub assembly. Install hub bolts, Part Number 47-641-194-1, in the tail rotor hub as specified in paragraph 6-16.e., Section IV, Models 47D-1, 47G, and 47G-2 Maintenance and Overhaul Instruction Manual, as revised August 15, 1961, or as specified by equivalent FAAapproved procedures. (d) Assemble and track and balance the tail rotor hub and blade assembly as specified in the pertinent Model Maintenance and Overhaul Instruction Manual or as specified in FAA approved equivalent procedures. (e) Compliance with Bell Helicopter Company Service Bulletin No. 47-76-1 dated January 5, 1976, or later approved revision fulfills compliance with this AD. This amendment becomes effective July 14, 1976.
2022-17-12: The FAA is adopting a new airworthiness directive (AD) for certain CFM International, S.A. (CFM) LEAP-1A model turbofan engines. This AD was prompted by reports of two in-flight shutdowns (IFSDs) and subsequent investigation by the manufacturer that revealed cracks in the high-pressure turbine (HPT) rotor stage 1 blades. This AD requires initial and repetitive borescope inspections (BSIs) of the HPT rotor stage 1 blades. Depending on the results of the BSIs, this AD requires either additional BSIs at reduced intervals or replacement of the HPT rotor stage 1 blades. This AD also requires sending the inspection results to CFM if any unserviceable finding is found. The FAA is issuing this AD to address the unsafe condition on these products.