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94-01-11: This amendment adopts a new airworthiness directive (AD), applicable to Airbus Model A320 series airplanes, that requires visual inspections and end-float checks of the ram air turbine (RAT), and replacement of the RAT, if necessary. This amendment is prompted by a report that, during an on-ground functional test of the RAT, the RAT broke away from its support leg. The actions specified by this AD are intended to prevent the RAT from breaking away from its support leg, which could damage the airplane structure and systems, and could injure ground personnel.
96-01-52: 96-01-52 AIRBUS: Amendment 39-9491. Docket 96-NM-03-AD. Applicability: Model A310 and A300-600 series airplanes; equipped with a trimmable horizontal stabilizer (THS) actuator having part number (P/N) 47142-201 or P/N 47142-203; certificated in any category. NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (c) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD. Compliance: Required as indicated, unless accomplished previously. To prevent runaway of the horizontal stabilizer to its full up or down position, subsequent reduced maneuvering capability, and a potential pitch upset, accomplish the following: (a) Within 12 days after the effective date of this AD, perform an inspection to ensure correct synchronization of the hydraulic control valves of the trimmable horizontal stabilizer (THS) actuator, in accordance with paragraph 4.2.2.1 of Airbus All Operators Telex (AOT) 27-21, Revision 1, dated January 5, 1996. (1) If the actuator is synchronized correctly, prior to further flight, perform a functional test of the THS in accordance with paragraph 4.2.2.1 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of thisAD at intervals not to exceed 500 hours time-in- service. (2) If the actuator is desynchronized slightly, as specified in the AOT, prior to further flight, adjust the synchronization, and perform a functional test of the THS, in accordance with paragraph 4.2.2.2 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service. (3) If the actuator is desynchronized significantly, as specified in the AOT, prior to further flight, accomplish either paragraph (a)(3)(i) or (a)(3)(ii) of this AD. Prior to further flight following the accomplishment of either of those paragraphs, adjust the synchronization, and perform a functional test of the THS, in accordance with paragraph 4.2.2.3 of the AOT. Thereafter, repeat the inspection required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service. (i) Remove and replace the hydraulic motors of the horizontal stabilizer actuator (HSA) with new or serviceable motors in accordance with procedures specified in the Airplane Maintenance Manual. Or (ii) Remove the hydraulic motors of the HSA and perform the various follow-on actions specified in paragraph 4.2.2.4 of the AOT, in accordance with that paragraph. (The follow-on actions include checking the motors and the cam seats, assembling the motors, and metal stamping the modification plate of the motors.) If any discrepancy is found during the check, prior to further flight, repair in accordance with paragraph 4.2.2.4 of the AOT. (b) For airplanes on which any maintenance action relating to a hydraulic motor or a hydraulic valve block of the HSA has occurred since the airplane was new: Within 12 days after the effective date of this AD, accomplish either paragraph (b)(1) or (b)(2) of this AD. (1) Replace both hydraulic motors of the HSA with new or serviceable motors in accordance with the procedures specified in the Airplane Maintenance Manual. Adjust the synchronization, and perform a functional test of the THS in accordance with paragraph 4.2.2.3 of Airbus AOT 27-21, Revision 1, dated January 5, 1996. Thereafter, perform the repetitive inspections required by paragraph (a) of this AD at intervals not to exceed 500 hours time-in-service. Or (2) Remove the hydraulic motors of the HSA and perform the various follow-on actions specified in paragraph 4.2.2.4 of the AOT, in accordance with that paragraph of the AOT. Adjust the synchronization, and perform a functional test of the THS in accordance with paragraph 4.2.2.3 of the AOT. (The follow-on actions include checking the motors and the cam seats, assembling the motors, and metal stamping the modification plate of the motors.) If any discrepancy is found during the check, prior to further flight, repair in accordance with paragraph 4.2.2.4 of the AOT. Thereafter, perform the repetitive inspections required by paragraph (a) of this AD at intervals not to exceed500 hours time-in-service. (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 2: 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 sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The actions shall be done in accordance with Airbus All Operators Telex (AOT) 27-21, Revision 1, dated January 5, 1996. 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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. 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 February 5, 1996, to all persons except those persons to whom it was made immediately effective by telegraphic AD T96-01-52, issued January 9, 1996, which contained the requirements of this amendment.
79-02-07: 79-02-07 HAWKER SIDDELEY AVIATION, LIMITED (BRITISH AEROSPACE): Amendment 39-3399. Applies to DH-104 "Dove" airplanes, all series, certificated in all categories, except those airplanes modified in accordance with STC SA1747WE. Compliance required as indicated. To prevent possible failure of the wing to fuselage attachment and loss of wing in flight, accomplish the following: (a) Within the next 100 hours time in service after the effective date of this AD, unless already accomplished, remove the port and starboard wing root fairings and inspect the upper three lugs at each end of the center section main spar top boom, P/N 4FS.135 A/1, for cracks using an ultrasonic method of inspection in accordance with Appendix 1 of Hawker Siddeley Aviation, Ltd., Technical News Sheet TNS 237, dated September 9, 1976, (hereinafter referred to as the Technical News Sheet) or an FAA-approved equivalent. NOTE: This inspection can be conducted with the wing installed. (b) If no cracks are found during the inspection required by paragraph (a) of this AD, repeat the inspection at intervals not to exceed 1200 flight hours or 2 calendar years, whichever occurs sooner, until the wings are removed for compliance with AD 72-16-07 at which time the area must be further inspected using the ultrasonic and dye penetrant methods in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent. Thereafter, if no cracking is found, continue to inspect the area as follows: (1) In accordance with the method specified in paragraph (a) of this AD at an interval not to exceed 3 calendar years from each time the area is inspected in conjunction with the wing removal required by AD 72-16-07; and (2) In accordance with the ultrasonic and dye penetrant methods specified in Appendix 2 of the Technical News Sheet or an FAA-approved equivalent at each time the wings are removed for compliance with AD 72-16-07. (c) If any cracks are found during any inspection required by this AD to be performed in accordance with the method specified in paragraph (a) of this AD, further inspect by ultrasonic and dye penetrant methods in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent with the wing removed. (d) If, during any inspection required by this AD, cracking of the lugs is found which is confined to only one of the lugs per side of the aircraft and exists only from the bolt hole towards the outboard end of the lug, the center section carry through boom may remain on the aircraft and continued flight is permitted provided the wing is removed at intervals not to exceed 300 flight hours or 3 months, whichever is sooner, and the cracked lug is inspected for crack propagation and the remaining two lugs are inspected for cracking, all in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent, until the boom is replaced with a new boom of the same part number or a used boom of the same part number determined after inspection in accordance with Appendix 2 of the Technical News Sheet to be crack-free. (e) If, during any inspection required by this AD, cracking is found in more one lug per side of the aircraft or the cracking of any one lug extends to both sides (inboard and outboard) of the bolt hole or runs from the bolt hole in an inboard direction only, before further flight, replace the carry through boom with a new boom of the same part number or a used boom of the same part number determined after inspection in accordance with Appendix 2 of the Technical News Sheet to be crack-free. Replacement booms must continue to be inspected in accordance with the following schedule: (1) For used replacement booms, within 3 years from replacement, inspect the lug area in accordance with Appendix 1 of the Technical News Sheet or an FAA-approved equivalent except if any wing removal is required by AD 72-16-07 during that period, inspect in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent concurrently with that wing removal. Thereafter inspect in accordance with the schedule and inspection methods specified in paragraphs (b)(1) and (b)(2) of this AD. (2) For new replacement booms, inspect the lug area in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent with the wing removed prior to accumulating 6 years in service and thereafter in accordance with the schedule and inspection methods specified in paragraphs (b)(1) and (b)(2) of this AD. However, if the first inspection required after replacement is not performed in conjunction with a wing removal required by AD 72-16-07, within the next 3 years after that inspection, inspect in accordance with Appendix 1 of the Technical News Sheet or an FAA-approved equivalent except if any wing removal is required by AD 72-16-07 during that period inspect in accordance with Appendix 2 of the Technical News Sheet or an FAA-approved equivalent concurrently with that wing removal and thereafter inspect in accordance with the schedule and inspection methods specified in paragraphs (b)(1) and (b)(2) of this AD. This amendment becomes effective February 19, 1979.
89-03-10: 89-03-10 BOEING: Amendment 39-6137.\n\tApplicability: Model 757 series airplanes, as listed in Boeing Service Bulletin 757-27-0076, dated May 19, 1988, certificated in any category.\n\n\tCompliance: Required within the next 24 months after the effective date of this AD, unless previously accomplished.\n\n\tTo prevent uncommanded extension of three flight spoilers on one wing, due to failure of a spoiler wheel command unit, accomplish the following:\n\n\tA.\tReplace both spoiler wheel command units, in accordance with Boeing Service Bulletin 757-27-0076, dated May 19, 1988.\n\n\tB.\tAn 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, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.\n\n\tNOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and then send it to the Manager, Seattle Aircraft Certification Office.\n\n\tC.\tSpecial flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the inspections required by this AD.\n\n\tAll persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington.\n\n\tThis amendment (39-6137, AD 89-03-10) becomes effective March 15, 1989.
82-20-01: 82-20-01 BENDIX: Amendment 39-4658. Applies to Bendix Engine Products Division magnetos with type designations listed below: \n\n\tCompliance required within the next 10 hours of engine operation unless already accomplished for all affected impulse couplings having less than 300 operating hours. (Compliance with this AD is not required for magneto impulse couplings having more than 300 operating hours.) \n\n\n\nS4LN-21/S4RN-21\nExcept Bendix Red Label magnetos above \nS6LN-21/S6RN-21\nSerial Nos. B-001171 or A297043\nS6LN-23/S6RN-23\n\n\n\nS4LN-1225/S4RN-1225\t\nExcept Bendix Red Label magnetos above\nS4LN-1225/S4RN-1227\nSerial Nos. B-001162 or A297043\nS6LN-1225/S6RN-1225\n\nS6LN-1227/S6RN\n\n1227 \n\n\n\nS4LN-200 P/N 10-163005-7\nExcept Bendix Red Label magnetos above \nSerial Nos. B-001732 or A297043. \n\n\nD4LN-2021/D4RN-2021\nExcept Bendix Red Label magnetos above\nD4LN-2031/D4RN-2031\nSerial Nos. 35550\nD4LN-2031/D4RN-2021 \n\nD6LN-2021/D6RN-2021\n\nD4LN-2031/D4RN-2031 \n\nD6LN-2031/D6RN-2031\n\n\n\nD4LN-3000/D6RN-3000\nExcept Bendix Red Label magnetos above \nSerial Nos. B-000249 or 5806. \n\n\nAll Blue Label impulse \t\ncoupled magnetos of the \nabove types. \nExcept Serial Nos. 8236001 and above. \n\n\tTo prevent failure of impulse coupling due to improperly heat treated (soft) flyweights resulting in engine damage or failure, accomplish the following: (Ref. Bendix Service Bulletin No. 623 dated September 1982.) \n\n\tNOTE: The magneto should be removed from the engine only to the extent necessary to perform the inspection described herein. Depending on the engine application, it may not be necessary to remove the harness from the magneto for the inspection procedure. \n\n\tNOTE: All magnetos with the impulse coupling recessed into the magneto flange must have the impulse coupling removed from the magneto to perform the inspection. This is a bench operation and will required the magneto to be completely removed from the engine and the harness removed from the magneto. \n\n\tNOTE: Whenever an impulse coupling is removed from a magneto, it must be removed following the manufacturer's published procedures, paying strict attention to notes and conditions. Upon reassembly, the castellated nut securing the impulse coupling to the drive shaft must be torqued to 15-25 ft. lb. (Emergency AD 82-20-01 issued September 7, 1982, specified 18-28 ft. lb. torque. If compliance has already been accomplished based on AD 82-20-01, it is not necessary to retorque to 15-25 ft. lb.) The cotter pin, Bendix P/N 10-90751-18 removed during disassembly, must be discarded and replaced. \n\n\t1.\tRemove the magneto from the engine in accordance with the engine/aircraft manufacturer's published instructions. \n\n\t2.\tPlace the magneto in a suitable work stand with the impulse coupling facing up. \n\n\t3.\tUse finger pressure to push inward on the toe (see Figure 1) of each flyweight so that the flyweight heel protrudes outward. \n\n\t4.\tUsing a fine #1, double cut,1/2-inch wide file at least 3/32-inch thick, pass the file across the heel of the flyweight attempting to remove material (see Figure 1). If the flyweight has been properly heat treated, the file will "glide" smoothly over the heel of the flyweight, removing no material. If the flyweight is not properly heat treated (soft), the file will not "glide" easily across the surface of the flyweight heel, and material will be removed. \n\n\t5.\tIf an improperly heat treated (soft) flyweight is found, immediately remove and replace the cam assembly and/or the impulse coupling assembly with an assembly meeting the requirements of this AD, following procedures in the magneto overhaul instructions, and paying strict attention to notes and cautions. \n\n\t6.\tInspect the impulse coupling stop pins for wear and replace as necessary. \n\n\t7.\tAfter flyweights have been identified, stop pins inspected, and the impulse coupling reinstalled on the magneto (if removed), identify the magneto by stamping a 1/16-inch letter "F" in the upper right corner of the identification plate to indicate that this AD and Bendix Service Bulletin No. 623 have been complied with. \n\n\t8.\tReinstall the magneto on the engine following the manufacturer's published procedures. \n\n\t9.\tMake an appropriate engine logbook entry, recording magneto serial number to indicate that this AD and Bendix Service Bulletin No. 623 have been complied with. \n\n\t10.\tInspect all spare impulse coupling assemblies, cam assemblies, and magnetos following the same procedures described in Steps 3 and 4 of this AD. If both flyweights are found acceptable, identify the cam assembly by applying yellow dyken or yellow lacquer to the heel of each flyweight. Stamp "F" on data plate as described in Step 7. \n\n\t11.\tAn equivalent method of compliance with this AD may be used if approved by the Manager, New York Aircraft Certification Office, Federal Aviation Administration, 181 South Franklin Avenue, Room 202, Valley Stream, New York 11581. \n\n\tThis amendment becomes effective June 14, 1983, as to all persons except those to whom it was made immediately effective by priority mail, issued September 19, 1982.
2020-12-06: The FAA is adopting a new airworthiness directive (AD) for all Gulfstream Aerospace Corporation (Gulfstream) Model G-IV airplanes. This AD was prompted by reports of un-commanded nose wheel steering turns. This AD requires replacing the nose wheel steering servo valve manifold, incorporating revised operating procedures into the airplane flight manual (AFM), doing a records inspection for any incidents of un-commanded nose wheel steering turns, and reporting the results to the FAA. The FAA is issuing this AD to address the unsafe condition on these products.
94-02-03: This amendment adopts a new airworthiness directive (AD), applicable to certain Fokker Model F28 Mark 0100 series airplanes that requires replacement of the existing attachment bolts on the horizontal stabilizer with new, improved bolts having a longer fatigue life. This amendment is prompted by a report that certain attachment bolts on the horizontal stabilizer were not properly treated on the surface during production, resulting in reduced fatigue life. The actions specified by this AD are intended to prevent corrosion and subsequent fatigue-related cracking of the attachment bolts on the horizontal stabilizer, which could lead to loss of stabilizer control.
99-09-17: 99-09-17 TELEDYNE CONTINENTAL MOTORS: Priority Letter issued on April 22, 1999. Docket No. 99-NE-28-AD. Applicability: Teledyne Continental Motors (TCM) O-470, IO-470, TSIO-470, IO-520, TSIO-520, LTSIO-520, IO-550, TSIO-550 and TSIOL-550 series new and rebuilt reciprocating engines, manufactured between January 1, 1998, and December 31, 1998, inclusive, listed by serial number (S/N) in TCM Critical Service Bulletin (CSB) 99-3, dated April 19, 1999, and any other engine from the above series that has had a new crankshaft installed that was manufactured between January 1, 1998, and December 31, 1998, inclusive. Note 1: Engine S/Ns can be found in log books or other maintenance records. For those engines that were overhauled in the field with factory new crankshafts, crankshaft S/Ns should be shown in work orders, log books, or other maintenance records. Note 2: This Priority Letter Airworthiness Directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (e) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it. Compliance: Required as indicated, unless accomplished previously. To prevent crankshaft failure due to No. 2 and No. 5 cheek cracks, which could result in total engine power loss, in-flight engine failure, and possible forced landing, accomplish the following: (a) For those engines listed by S/N on pages 3 through 12 of TCM CSB99-3 dated April 19, 1999, with 300 hours or less time-in-service (TIS) upon receipt of this priority letter AD, perform the crankshaft visual and ultrasonic (UT) inspections within 10 hours TIS after receipt of this priority letter AD, in accordance with sections A and B of TCM CSB 99-3, dated April 19, 1999. These inspections must be performed by TCM representatives. (1) If a crack is found, replace the crankshaft with a serviceable crankshaft of the same part number (P/N) prior to further flight. (2) If no crack is found, reassemble the engine and return it to service. (b) For those engines listed by S/N on pages 3 through 12 of TCM CSB 99-3, dated April 19, 1999, with more than 300 hours TIS upon receipt of this priority letter AD, perform the crankshaft visual and UT inspections at the next maintenance event, or within 50 hours TIS after receipt of this priority letter AD, whichever occurs first, in accordance with sections A and B of TCM CSB 99-3, dated April 19, 1999. These inspections must be performed by TCM representatives. (1) If a crack is found, replace the crankshaft with a serviceable crankshaft of the same P/N prior to further flight. (2) If no crack is found, reassemble the engine and return it to service. (c) For any other engine with a crankshaft installed that was manufactured between January 1, 1998, and December 31, 1998, with 300 hours or less TIS upon receipt of this priority letter AD, perform the crankshaft visual and UT inspections within 10 hours TIS after receipt of this priority letter AD, in accordance with sections A and B of TCM CSB 99-3, dated April 19, 1999. These inspections must be performed by TCM representatives. (1) If a crack is found, replace the crankshaft with a serviceable crankshaft of the same P/N prior to further flight. (2) If no crack is found, reassemble the engine and return it to service. (d) For any other engine with a crankshaft installed that was manufactured between January 1, 1998, and December 31, 1998, with more than 300 hours TIS upon receipt of this priority letter AD, perform the crankshaft visual and UT inspections at the next maintenance event, or within 50 hours TIS after receipt of this priority letter AD, whichever occurs first, in accordance with sections A and B of TCM CSB 99-3, dated April 19, 1999. These inspections must be performed by TCM representatives. (1) If a crack is found, replace the crankshaft with a serviceable crankshaft of the same P/N prior to further flight. (2) If no crack is found, reassemble the engine and return it to service. Note 3: Engines and crankshafts that are the subject of this priority letter AD were manufactured between January 1, 1998, and December 31, 1998, inclusive. Purchase and delivery dates of engines/crankshafts produced in December 1998 could have been in the January/February 1999 time frame and are therefore affected by this AD. Likewise, engines/crankshafts purchased/delivered in January/February 1998 could have been December 1997 production and are not affected by this AD. Use the S/N of the engine or crankshaft to determine applicability: engine S/Ns are listed in TCM CSB 99-3, dated April 19, 1999, while the crankshafts, not listed by S/N, were manufactured during 1998. See Note 4 for information on identifying crankshafts. Note 4: The following information is provided to avoid confusion in crankshaft S/N interpretation. A typical crankshaft S/N could be C229805N. The first letter is the month of manufacture beginning with A - January and ending with L - December; therefore, C is March. The next two digits are the day of the month; in this example, the 22nd. The next two digits are the year; in this example 1998. The final two digits are the sequential number of the crankshaft for a given day; in the example, this was the 5th crankshaft produced that day. The final letter, "N", identifies this as a crankshaft S/N. Therefore, for this example: we have the 5th crankshaft produced on March 22, 1998. For all practical purposes, you only need look for the year, i.e. 98 (fourth and fifth positions in the S/N sequence) because that will determine AD effectivity. The crankshaft S/N is stamped on the edge of the propeller flange. Note 5: The engine S/Ns listed in TCM CSB 99-3 contain only the numerical portion of the S/N. Rebuilt engines will have the letter "R" at the end of the six digit numerical portion while new engines use only the six digit numerical sequence. (e) 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, Atlanta Aircraft Certification Office. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta Aircraft Certification Office. Note 6: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Atlanta Aircraft Certification Office. (f) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished. (g) Copies of the applicable service information may be obtained from Teledyne Continental Motors, PO Box 90, Mobile, AL 36601; telephone toll free (888) 826-5874. This information may be examined at the FAA, New England Region, Office of the Regional Counsel, 12 New England Executive Park, Burlington, MA. (h) Priority Letter AD 99-09-17, issued April 22, 1999, becomes effective upon receipt.
88-07-04: 88-07-04 BOEING: Amendment 39-5881. Applies to Model 737 series airplanes, as listed in Boeing Service Bulletin 737-32-1202, dated August 27, 1987, certificated in any category. Compliance required within the next six months after the effective date of this AD, unless previously accomplished.\n \n\tTo prevent damage to the hydraulic systems and loss of brakes and nose wheel steering, accomplish the following: \n\n\tA.\tInstall left and right main landing gear brake metering valve tire burst guards in accordance with Boeing Service Bulletin 737-32-1202, dated August 27, 1987, or later FAA- approved revision. \n\n\tB.\tAn alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety and which has the concurrence of an FAA Principal Maintenance Inspector, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. \n\n\tC.\tSpecial flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. \n\n\tAll persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or at the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. \n\n\tThis amendment becomes effective May 1, 1988.
2020-12-07: The FAA is adopting a new airworthiness directive (AD) for certain Hamilton Sundstrand Corporation (Hamilton Sundstrand) 54H60 model propellers. This AD was prompted by the failure of a propeller blade that resulted in the loss of the airplane. This AD requires initial and repetitive eddy current inspections (ECIs) of the affected propeller blades and replacement of the propeller blades that fail the inspection. The FAA is issuing this AD to address the unsafe condition on these products.