Results
97-22-16: This amendment adopts a new airworthiness directive (AD) that applies to certain Raytheon Aircraft Company (Raytheon) Models 1900, 1900C, and 1900D airplanes (formerly referred to as Beech Models 1900, 1900C, and 1900D airplanes). This AD requires fabricating and installing a placard that restricts the use of the forward and aft vent blower assemblies to only the "OFF" or "HIGH" position. This AD also requires incorporating a modification that would replace the bearings on the vent blower assemblies with improved design bearings, and provide thermal protection for the vent blowers, as applicable. Incorporating the modification will eliminate the need for the placard. The AD results from reports of vent blower assembly bearings seizing and locking the blower motor on several of the affected airplanes. The actions specified by this AD are intended to prevent the vent blower assembly bearings from seizing, which could result in smoke emanating from the insulating material covering the electrical wiring and entering the airplane cabin.
2012-06-17: We are adopting a new airworthiness directive (AD) for certain [[Page 16918]] Rolls-Royce Deutschland (RRD) Models Tay 611-8 and Tay 611-8C turbofan engines. This AD requires replacement of the high-pressure (HP) turbine spanner retaining nut. This AD was prompted by the discovery that certain HP turbine spanner retaining nuts were improperly heat treated after application of silver plating. We are issuing this AD to prevent failure of the HP turbine stage 2 disc, uncontained engine failure, and damage to the airplane.
2012-06-05: We are adopting a new airworthiness directive (AD) for certain Bombardier, Inc. Model DHC-8-400 series airplanes. This AD was prompted by a report of the inability to open the airstair door while on the ground, because the airstair door seal did not deflate, which prevented the airstair door from opening. This AD requires changing the wiring that controls the pneumatic shut-off valve. We are issuing this AD to prevent the airstair door seal from not deflating, which could result in the airstair door not opening and could impede evacuation in the event of an emergency.
92-18-11: 92-18-11 BEECH: Amendment 39-8356. Docket No. 92-CE-28-AD. Applicability: Model A36 airplanes (serial numbers E-1946, E-2104, and E-2111 through E-2682), and Model B36TC airplanes (serial numbers EA-320, and EA-389 through EA-524), certificated in any category. Compliance: Required within the next 50 hours time-in-service after the effective date of this AD, unless already accomplished. To prevent failure of the landing gear circuit, which could result in the inability to extend the landing gear, accomplish the following: (a) Seal the upper door upper hinge cavity in accordance with the ACCOMPLISHMENT INSTRUCTIONS section of Beech Service Bulletin No. 2437, dated April 1992. (b) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (c) An alternative method of compliance or adjustment of the compliance time that provides an equivalentlevel of safety may be approved by the Manager, Wichita Aircraft Certification Office, FAA, 1801 Airport Road, Mid-Continent Airport, Wichita, Kansas 67209. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita Aircraft Certification Office. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita Aircraft Certification Office. (d) The modification required by this AD shall be done in accordance with Beech Service Bulletin No. 2437, dated April 1992. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from the Beech Aircraft Corporation, Commercial Service, Department 52, P.O. Box 85, Wichita, Kansas 67201-0085. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC. (e) This amendment becomes effective on October 18, 1992.
97-22-14: This amendment adopts a new airworthiness directive (AD) that is applicable to General Electric Company (GE) CF6-50 and -80C2 series turbofan engines. This action requires removal from service of defective high pressure compressor rotor (HPCR) stage 3-9 spools, and replacement with serviceable parts. This amendment is prompted by a report of an uncontained failure of an HPCR stage 3-9 spool installed on a GE model CF6-80C2 turbofan engine. The actions specified in this AD are intended to prevent failure of the HPCR stage 3-9 spool, which can result in an uncontained engine failure and damage to the aircraft.
97-22-09: This amendment adopts a new airworthiness directive (AD) that applies to all Dornier Luftfahrt GMBH (Dornier) Models 228-100, 228-101, 228-200, 228-201, 228-202, and 228-212 airplanes. This AD requires amending the Limitations Section of the Dornier 228 Pilot's Operating Handbook (POH) to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight. This POH amendment will include a statement of consequences if the limitation is not followed. This AD results from numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight. The actions specified by this AD are intended to prevent loss of airplane control or engine overspeed with consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight. EFFECTIVE DATE: December 5, 1997.
87-03-09: 87-03-09 WYTWORNIA SPRZETU KOMUNIKACYJNEGO, PZL-MIELEC: Amendment 39-5522. Applies to Model M18 Dromader (Serial Number 1Z001-01 through 1Z014-30, and 1Z015-01 through 1Z016-03) airplanes certificated in any category. Compliance: Required as indicated after the effective date of this AD, unless already accomplished. To prevent loosening of the engine mount shock absorber nuts, accomplish the following: (a) Within the next 100 hours time-in-service (TIS), replace all 0.8mm safety wire on the M6400- 105 nuts with 1.0 to 1.2mm (0.039 inch to 0.047 inch) wire as described in paragraph III.1, PZL-Mielec M18 Mandatory Service Bulletin (MSB) No. E/02.082/85 dated September 6, 1985. (b) Within the next 100 hours TIS and at each 100 hours TIS thereafter, visually inspect the Part Number M6400-105 nuts for security. If loose, prior to further flight, tighten and secure as described in paragraph III.2 of the subject MSB. (c) Within the next 600 hours TIS or the nexttime the engine frame is removed, whichever occurs first, perform the engine frame modification described in paragraph III.3 of the subject MSB. (d) The actions in paragraph (b) of this AD may be discontinued after accomplishment of the modification described in paragraph (c) of this AD. (e) Aircraft may be flown in accordance with Federal Aviation Regulation 21.197 to a location where this AD can be accomplished. (f) The intervals between the repetitive inspections required by this AD may be adjusted up to 10 percent of the specified interval to allow accomplishment of these inspections concurrent with other scheduled maintenance on the airplane. (g) An equivalent means of compliance with this AD, if used, must be approved by the Manager, Aircraft Certification Staff, AEU-100, Europe, Africa and Middle East Office, FAA, c/o American Embassy, B- 1000 Brussels, Belgium. All persons affected by this directive may obtain copies of the documents referred to hereinupon request to Wytwornia Sprzetu Komunikacyjnego; or FAA, Office of the Regional Counsel, Room 1558, 601 East 12th Street, Kansas City, Missouri 64106. This amendment becomes effective on March 1, 1987.
2012-06-07: We are superseding an existing airworthiness directive (AD) for certain Model A330-200 and -300 series airplanes, and Model A340- 200, -300, -500, and -600 series airplanes. This AD was prompted by reports of loose pneumatic quick-disconnect unions on Goodrich pitot probes that might be the result of mis-torque of the affected unions at equipment manufacturing level. This AD adds airplanes to the AD applicability. We are issuing this AD to detect and correct loose unions on the pitot probes, which could lead to an air leak, resulting in incorrect total pressure measurement and consequent erroneous calibrated airspeed (CAS)/MACH parameters delivered to the flightcrew by the air data computer.
97-22-08: This amendment adopts a new airworthiness directive (AD) that applies to certain Pilatus Aircraft LTD (Pilatus) Models PC-6/B1-H2, PC-6/B2-H2, PC-6/B2-H4 airplanes and all Pilatus Model PC-12 airplanes. This AD requires amending the Limitations Section of either the airplane flight manual (AFM) or the pilot's operating handbook (POH) to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight. This AFM amendment will include a statement of consequences if the limitation is not followed. This AD results from numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight. The actions specified by this AD are intended to prevent loss of airplane control or engine overspeed with consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.
72-16-03: 72-16-03 GENERAL ELECTRIC: Amendment 39-1495. Applies to Models CF6-6D and CF6-6D1 turbofan engines. Compliance required as indicated. To prevent cracking and possible failure of stage 2 high pressure turbine discs, unless already accomplished, remove from service stage 2 high pressure turbine discs Part No. 9687M40P03, P04, P05, or P06 prior to reaching a life limit of 2100 cycles. For the purposes of this AD, the definition of cycles is that appearing in the CF6 Shop Manual GEK 9266 Section 72-00-00 Inspection page 301. (General Electric Alert Service Bulletin CF6 72-320 pertains to this subject.) This amendment is effective August 8, 1972.
93-05-18: 93-05-18 FOKKER: Amendment 39-8522. Docket 92-NM-180-AD. Applicability: Model F28 Mark 0100 airplanes, serial numbers 11244 through 11356, inclusive; certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent jamming of the servo and to ensure that the stabilizer can be repositioned after an uncommanded trim movement, accomplish the following: (a) Within 400 hours time-in-service after the effective date of this AD, unless accomplished previously within the last 1,600 hours time-in-service, inspect the end-cap of the horizontal stabilizer dual actuator servo valve manifold to detect moisture in accordance with Fokker Service Bulletin SBF100-27- 029, dated January 29, 1991. Prior to further flight, remove any moisture found in accordance with the service bulletin. (b) Within 2,000 hours time-in-service or one year after the effective date of this AD, whichever occurs first, modify the end-cap of the servo valve of the horizontal stabilizer hydraulic actuator in accordance with Fokker Service Bulletin SBF100-27-032, dated September 20, 1991, as revised by Fokker Service Bulletin Change Notification SBF100-27-032/01, dated October 19, 1992. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The inspection shall be done in accordance with Fokker Service Bulletin SBF100-27-029, dated January 29, 1991. The modification shall be done in accordance with Fokker Service Bulletin SBF100-27-032, dated September 20, 1991; and Fokker Service Bulletin Change Notification SBF100-27- 032/01, dated October 19, 1991 (for Fokker Service Bulletin SBF100-27-032, dated September 20, 1991). This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Fokker Aircraft USA, Inc., 1199 North Fairfax Street, Alexandria, Virginia 22314. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (f) This amendment becomes effective on May 14, 1993.
2012-05-08: We are adopting a new airworthiness directive (AD) for all Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model ERJ 170 airplanes. This AD requires repetitive inspections for fuel leakage and cracks on the wing spar II, close to the rib 10 area, and repair if necessary. This AD was prompted by reports of fuel seepage at the left- hand wing, close to the rib 10 area in two airplanes. We are issuing this AD to detect and correct cracking on the wing spar II, which could result in a fuel leak, consequent reduced structural integrity of the airplane, and possible fire.
47-20-05: 47-20-05 ERCO: (Was Mandatory Note 13 of AD-718-6.) Applies to 415-C, -CD and -D Aircraft Serial Numbers 800 Through 2037. Compliance required prior to October 1, 1947. Cracks have occurred in the belly skin at the rearmost rivet attaching the center section belly skin outer stiffeners (Erco P/N 415-13056 L/R) to the belly skin. To prevent similar failures where cracks have not yet developed, install 0.064-inch 24ST alclad angles 1/2-inch wide with legs of 1 3/32 inches and 1/2 inch (Erco P/N 415-13068). Attach the 1 3/32-inch leg to the outboard side of the aft end of each belly skin outer stiffener with two AN 470AD3-4 rivets (3/32-inch diameter, universal head, A17ST, 1/4-inch long) and to the center section rear beam with one AN 470AD3-5 rivet. (AN 430 type round head rivets may be used.) If cracks are found in the belly skin, drill relief holes at the ends of the cracks and install triangular shaped patch plates as follows in addition to the angle stiffeners described above. Prepare the patch plates of 0.032-inch 24ST alclad material of such a shape that it will pick up the last two rivets which attach the aft end of the belly skin outer stiffener to the belly skin and the three rivets attaching the rear beam to the belly skin which are in line with and to either side of the stiffener. Remove the above-mentioned existing rivets and attach the patch plates through these holes using AN 470AD3-3 and -4 rivets. Attach the patch plate to the belly skin with six additional AN 470AD3-3 rivets, three through each side of each plate. (Erco's Ercoupe Service Department Bulletin No. 18 dated January 9, 1947, covers this same subject.)
97-22-11: This amendment adopts a new airworthiness directive (AD) that applies to all Industrie Aeronautiche e Meccaniche Rinaldo Piaggio S.p.A. (Piaggio) Model P-180 airplanes. This AD requires amending the Limitations Section of the airplane flight manual (AFM) to prohibit the positioning of the power levers below the flight idle stop while the airplane is in flight. This AFM amendment will include a statement of consequences if the limitation is not followed. This AD results from numerous incidents and five documented accidents involving airplanes equipped with turboprop engines where the propeller beta was improperly utilized during flight. The actions specified by this AD are intended to prevent loss of airplane control or engine overspeed with consequent loss of engine power caused by the power levers being positioned below the flight idle stop while the airplane is in flight.
59-01-01: 59-01-01 CONVAIR: Applies to All 240 and 340 Aircraft and to 440, Serial Nos. 312 Through 502. Compliance required as follows: 440 aircraft not later than December 31, 1958; 340 and 240 aircraft not later than April 30, 1960. Inflight fire experience and fire tests on the Convair engine nacelle have shown the need for further improvement in detecting fires originating in zones one and two. Additional continuous type detector coverage was provided in production 440 aircraft for the zone one bellmouth and zone two chimney areas. Because of false warnings the original system was rendered inoperative by Convair Service Air Gram No. 173, and an improvement program was initiated. This program has now been completed and a revised system developed with functional reliability proven by test under laboratory and service conditions. To improve and reactivate the continuous type fire detector system installation on 440 aircraft and to provide equivalent coverage for 240 and 340aircraft, the following must be accomplished: (1) On 440 aircraft, the existing continuous type fire detector system must be modified to incorporate improved detector elements and assemblies, including connectors, control box cannon plugs and mounting provisions. Upon accomplishment, the continuous type system must be made operative. On aircraft of Serial Nos. 503 and subsequent which incorporate these changes, the system must be maintained operative. (Convair Service Bulletin No. 440-41 covers an acceptable method of accomplishing these changes.) (2) On 240 and 340 aircraft, either modification (a) or modifications (b) and (c) must be accomplished: (a) Install additional fire detector coverage consisting of a continuous type system installed in each augmenter bellmouth and each vent chimney, similar to that now installed on 440 aircraft. The airplane flight manual must be revised to include a description of the system operation and the required emergency procedures. (Convair Service Bulletin No. 340-222 covers an acceptable method of accomplishment of this installation on 340 aircraft. Service bulletins applicable to 240 aircraft will be published at a later date, if there is a request for such information from operators desiring to accomplish this in preference to the modifications described in items (b) and (c) following.) (b) Install at least three unit-type detectors at each augmenter tube bellmouth or on brackets mounted on the shroud or engine cowling and located in close proximity to the bellmouths, such as to be in the path of flames which would enter the bellmouth in the event of fire. Existing detectors at the upper cowl flaps and those mounted on the upper side shroud panels may be counted among the three units specified, provided they are installed in accordance with Convair Bulletins No. 240-419 and No. 240-419A or conform to original Model 340 production configuration. The third bellmouth detector location must conformwith figure 6 of Technical Development Center Report No. 250. Revised detector installations must be ground and flight tested in accordance with Thomas A. Edison Installation Manual, Publication No. 1058, dated July 15, 1950, to assure correct circuit adjustment. (c) To minimize flame stratification and improve effectiveness of present fire detection, a reduction in airflow rate in zone two must be effected by modifications in accordance with Convair Service Bulletin 340-176 or equivalent for the 340 aircraft, and in accordance with Convair Service Bulletin 240-473 or equivalent for the 240 aircraft. This supersedes AD 58-10-01.
2006-13-06: The FAA is adopting a new airworthiness directive (AD) for Rolls-Royce Corporation 250-B and 250-C series turboprop and turboshaft engines with certain part numbers (P/Ns) of gas producer rotor assembly tie bolts manufactured by EXTEX Ltd., Pacific Sky Supply Inc., Rolls- Royce Corporation (RRC), and Superior Air Parts Inc. This AD requires operators to remove from service affected gas producer rotor assembly tie bolts, and install serviceable tie bolts. This AD results from eleven reports of RRC tie bolt failure due to high cycle fatigue. We are issuing this AD to prevent tie bolt failure that could cause loss of engine power, resulting in a first stage turbine wheel overspeed and an uncontained engine failure.
76-02-01: 76-02-01 CONSOLIDATED AERONAUTICS: Amendment 39-2494. Applies to all Model LA-4 and Model LA-4-200 airplanes equipped with STC SA876EA auxiliary fuel tanks. Compliance required, as indicated, by the effective date of this Amendment. To prevent engine power interruption resulting from water contamination of the fuel system due to water entering the auxiliary fuel tank sumps, accomplish the following: Install the following placard adjacent to the auxiliary tank fuel transfer switches: "WARNING" "Auxiliary tank fuel transfer prohibited unless auxiliary tank sumps are drained free of water after each water operation." This amendment becomes effective January 30, 1976.
98-02-05: This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-02-05, which was sent previously to all known U.S. owners and operators of Cessna Aircraft Company (Cessna) Model 172R airplanes. This AD requires de-activating the cabin heating system until the engine exhaust muffler can be replaced, and fabricating and installing a placard within the pilot s clear view, using 1/8-inch letters with the following words: "CABIN HEATER INOPERATIVE." Inadequate or failed weldments that are leaking exhaust gas (including carbon monoxide) from the muffler into the airplane s cabin and cockpit area prompted this action. The actions specified by this AD are intended to prevent carbon monoxide gas from entering the airplane s cabin heating system and cabin, which, if not corrected, could result in passenger and pilot injury with consequent loss of control of the airplane.
2012-02-01: We are adopting a new airworthiness directive (AD) for Pratt & Whitney (PW) PW2037, PW2037(M), and PW2040 turbofan engines with certain fan blades with a cutback leading edge, installed. This AD was prompted by reports from PW that fan blade leading edge erosion can result in a fan thrust deterioration mode (FTDM) condition, a condition that cannot be detected by the crew, and that reduces the engine's capability of producing required thrust. This AD requires initial and repetitive maintenance to the leading edge of cutback fan blades or applying performance decrements as specified in the Airplane Flight Manual. [[Page 16140]] We are issuing this AD to correct undetectable fan thrust deterioration on these PW products.
2012-05-04: The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 767 airplanes. This AD requires an inspection of the number 2 windows to \n\n((Page 16148)) \n\ndetermine whether the link arms are in the over-center position, and modifying the link arms of the number 2 windows in the flight compartment if necessary. This AD also requires the inspection, and modification if necessary, for airplanes that replace a modified assembly with an unmodified assembly. This AD results from reports of the number 2 windows opening during takeoff roll, which has resulted in aborted takeoffs. We are issuing this AD to prevent the opening of the number 2 windows during takeoff roll, which could adversely affect the flightcrew's ability to perform critical takeoff communication and result in an aborted takeoff or an unscheduled landing.
97-22-07: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 737 series airplanes, that currently requires repetitive inspections to detect cracking of the lower skin at the lower row of fasteners in the lap joints of the fuselage, and repair of any cracking detected. This amendment requires that the inspections be accomplished at more frequent intervals. This amendment also adds a requirement for modification of the fuselage lap joints at certain locations, which constitutes terminating action for repetitive inspections of modified areas. This amendment is prompted by reports of numerous fatigue cracks in the lower skin of the fuselage lap joints at the lower row of fasteners. The actions specified in this AD are intended to prevent such fatigue cracking, which could result in sudden decompression of the airplane.
97-22-05: This amendment adopts a new airworthiness directive applicable to certain McDonnell Douglas Model DC-9 series airplanes and C-9 (military) series airplanes, that requires modification of the emergency internal release system of the tailcone and the accessory compartment. This amendment is prompted by a report that, due to failure of the tailcone release system, the tailcone did not deploy on an airplane during an emergency evacuation. The actions specified by this AD are intended to ensure that the emergency internal release system of the tailcone performs its intended function in the event of an emergency evacuation. The actions also are intended to prevent people on board the airplane from striking their heads on exposed metal frames in the tailcone area, which could cause injury and delay or impede their evacuation during an emergency.
2012-04-15: We are superseding an existing airworthiness directive (AD) for all Pratt & Whitney (PW) JT9D series turbofan engines. That AD currently requires revisions to the Airworthiness Limitations Section (ALS) of the manufacturer's Instructions for Continued Airworthiness (ICA) to include required enhanced inspection of selected critical life-limited parts at each piece-part opportunity. This new AD requires additional revisions to the JT9D series engines ALS sections of the manufacturer's ICA. This AD was prompted by the need to require enhanced inspection of selected critical life-limited parts of JT9D series engines. We are issuing this AD to prevent critical life-limited rotating engine part failure, which could result in an uncontained engine failure and damage to the airplane.
91-22-51: 91-22-51 BOEING: Amendment 39-8129. Docket 91-NM-214-AD. Final Rule of Telegraphic AD T91-22-51. \n\n\tApplicability: Model 757 series airplanes, line numbers 140 through 335, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent the separation of the trailing edge wedges from the airplane, accomplish the following: \n\n\t(a)\tPerform a close detailed visual inspection of the trailing edge wedges of slats 1 through 4 and 7 through 10, for delamination and physical damage in accordance with Boeing Alert Service Bulletin 757-57A0045, dated October 16, 1991, at the times specified below: \n\n\t\t(1)\tFor airplanes that have accumulated 5,000 or more flight hours as of the effective date of this AD: Within the next 10 calendar days after the effective date of this AD, and thereafter at intervals not to exceed 300 flight hours. \n\n\t\t(2)\tFor airplanes that have accumulated less than 5,000 flight hours as of the effective date of this AD: Within the next 300 flight hours after the effective date of this AD, and thereafter at intervals not to exceed 300 flight hours. \n\n\t(b)\tWithin the next 300 flight hours after the effective date of this AD, perform a "coin-tap" inspection of the trailing edge wedges of slats 1 through 4 and 7 through 10 for delamination and physical damage, in accordance with Boeing Alert Service Bulletin 757- 57A0045, dated October 16, 1991, Repeat this inspection at intervals not to exceed 1,500 flight hours. \n\n\t(c)\tIf delamination and/or physical damage are found as a result of the inspections required by paragraph (a) or (b) of this AD, prior to further flight, repair in accordance with an FAA-approved procedure or replace with new parts. If a repair is accomplished or if new parts are installed, the inspections required by paragraphs (a) and (b) of this AD must be continued. \n\n\t(d)\tAn 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\tNOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO. \n\n\t(e)\tSpecial 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. \n\n\t(f)\tThe inspections required by this AD shall be done in accordance with Boeing Alert Service Bulletin 757-57A0045, dated October 16, 1991. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. \n\n\t(g)\tThis amendment (39-8129, AD 91-22-51) becomes effective on January 24, 1992, to all persons except those persons to whom it was made immediately effective by telegraphic AD T91-22-51, issued October 17, 1991, which contained the requirements of this amendment.
97-22-02: This amendment adopts a new airworthiness directive (AD) that applies to Pilatus Britten-Norman Ltd. (PBN) BN-2, BN-2A, BN-2B, and BN-2T series airplanes. This action requires modifying the upper engine mounting brackets on the wing front spar as terminating action for the repetitive inspections that were required in AD 84-23-06. AD 84-23-06 is being revised in a separate action, deleting the Pilatus BN-2, BN-2A, BN-2B, and BN-2T series airplanes from its applicability. This AD is prompted by several reports of cracks in the upper engine mounting brackets and a new terminating action to eliminate the repetitive inspections for Pilatus BN-2, BN-2A, BN-2B, and BN-2T series airplanes. The actions specified by this AD are intended to prevent the failure of the upper engine mounting brackets on the wing mounted engines, which could possibly cause structural failure of the airplane.