AD 99-20-09
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-100 Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-100B Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-100B SUD Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200B Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200C Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200F Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-300 Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400 Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400D Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400F Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747SP Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747SR Series | Airworthiness Directives; BOEING Model 747 Series Airplanes |
Unsafe Condition
Separation of the engine from the airplane due to migration of the tangential link upper bolt.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the tangential link upper bolt nut orientation and torque value per Boeing Service Bulletin. Correct improper orientation or torque by removing and reinstalling parts or replacing with serviceable parts. Repeat inspections every 18 months. Replace bolt, nut, or safety links if missing or damaged as per the bulletin.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 90 days after February 16, 1996, or prior to further flight if discrepancies are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 747 series airplanes listed in Boeing Alert Service Bulletin 747-71A2277 or Service Bulletin 747-71A2277 Revisions 1 or 2.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tangential Link Upper Bolt Nut
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_99-20-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 99-20-09 Document Type: AD Final Rules Docket Number: 98-NM-277-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Tangential Link Upper Bolt Nut Status: Current Citation: (Federal Register: October 04, 1999 (Volume 64, Number 191)) Citation Publish Date: 10/04/1999 Effective Date: 02/16/1996 Make: The Boeing Company Model: 747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...Show more Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: 96-03-01 R1 Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 (64 FR 53621 No. 191 10/04/99) Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 99-20-09 CITATION: [Federal Register: October 04, 1999 (Volume 64, Number 191)] PAGE NUMBER: [Page 53621] DOCKET NUMBER: 98-NM-277-AD AMENDMENT: 39-11339 AD NUMBER: 99-20-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: Final rule SUMMARY: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes, that currently requires inspections of the lower engine mount to determine if the tangential link upper bolt and nut are oriented properly, and if the tangential link upper bolt nut is torqued within certain limits. Additionally, that amendment requires replacement of the bolt and nut with serviceable parts, if necessary, and requires certain follow-on actions for airplanes on which the upper bolt is missing. This amendment requires accomplishment of a previously optional terminating action or a new alternative terminating action for the repetitive inspections. This amendment is prompted by development of a new terminating action by the manufacturer. The actions specified by this AD are intended to prevent separation of the engine from the airplane due to migration of the tangential link upper bolt. DATES: Effective November 8, 1999. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of November 8, 1999. The incorporation by reference of Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, listed in the regulations, was approved previously by the Director of the Federal Register as of February 16, 1996 (61 FR 10270, March 13, 1996). ADDRESSES: The service information referenced in this AD may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. FOR FURTHER INFORMATION CONTACT: Tamara L. Anderson, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2771; fax (425) 227-1181. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 96-03-01 R1, amendment 39-9538 (61 FR 10270, March 13, 1996), which is applicable to certain Boeing Model 747 series airplanes, was published in the Federal Register on July 16, 1999 (64 FR 38379). The action proposed to continue to require inspections of the lower engine mount to determine if the tangential link upper bolt and nut are oriented properly, and if the tangential link upper bolt nut is torqued within certain limits. Additionally, that action also proposed to continue to require replacement of the bolt and nut with serviceable parts, if necessary, and requires certain follow-on actions for airplanes on which the upper bolt is missing. That action also proposed to require accomplishment of either a previously optional terminating action or a new, alternative terminating action for the repetitive inspections. Comments Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. The commenter supports the proposed rule. Conclusion After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. Cost Impact There are approximately 421 airplanes of the affected design in the worldwide fleet. The FAA estimates that 185 airplanes of U.S. registry will be affected by this AD. The inspections that are currently required by AD 96-03-01 R1 take approximately 16 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $177,600, or $960 per airplane, per inspection cycle. The replacement of the safety link that is required as one option for compliance with this AD action will take approximately 18 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $30,228 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $31,308 per airplane. In lieu of replacement of the safety link, this AD provides for replacement of the tangential link upper bolt on the aft engine mount with a reworked bolt and a new nut retainer. Such replacement, which is provided as an additional option for compliance with this AD action, will take approximately 20 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $1,888 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $3,088 per airplane. The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. Regulatory Impact The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39 - AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. Section 39.13 is amended by removing amendment 39-9538 (61 FR 10270, March 13, 1996), and by adding a new airworthiness directive (AD), amendment 39-11339, to read as follows: REGULATORY TEXT: 99-20-09 BOEING: Amendment 39-11339. Docket 98-NM-277-AD. Supersedes AD 96-03-01 R1, amendment 39-9538. Applicability: Model 747 series airplanes, as listed in Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995; or Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999; certificated in any category. NOTE 1: This AD applies to each airplane 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 airplanes 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 (c)(1) 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 separation of the engine from the airplane, accomplish the following: RESTATEMENT OF REQUIREMENTS OF AD 96-03-01 R1, AMENDMENT 39-9538: Inspections and Corrective Actions (a) Within 90 days after February 16, 1996 (the effective date of AD 96-03-01 R1, amendment 39-9538), accomplish the requirements of paragraphs (a)(1) and (a)(2) of this AD in accordance with Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, or Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999. (1) Perform a visual inspection to ensure that installation of the tangential link upper bolt nut is on the forward side of the engine mount fitting. (i) If the tangential link upper bolt nut is installed on the forward side of the engine mount fitting, repeat the visual inspection at intervals not to exceed 18 months. (ii) If the tangential link upper bolt nut is not installed on the forward side of the engine mount fitting, prior to further flight, remove the nut, bolt, and washers, and reinstall the nut, bolt, and washers in accordance with the service bulletin. Thereafter, repeat the visual inspection at intervals not to exceed 18 months. (iii) If the tangential link upper bolt is missing from the engine mount fitting, prior to further flight, perform the various follow-on actions in accordance with the service bulletin. (The follow-on actions include visual inspections, magnetic particle inspections, replacement of the lower engine mount fitting with a serviceable part, if necessary; installation of new safety links, bolts, and nuts; and installation of a new tangential link upper bolt.) Thereafter, repeat the visual inspection at intervals not to exceed 18 months. (2) Perform an inspection to verify that the torque value of the tangential link upper bolt (on both sides of the mount) is within the limits specified in the service bulletin. (i) If the torque value of the tangential link upper bolt nut is within the limits specified in the service bulletin, repeat the inspection (verification) at intervals not to exceed 18 months. (ii) If the torque value of the tangential link upper bolt nut is outside the limits specified in the service bulletin, prior to further flight, perform a visual inspection of the tangential link upper bolt and washer for any damage or discrepancy, in accordance with the service bulletin. (A) If no damage or discrepancy of the tangential link upper bolt and washers is found, prior to further flight, replace the bolt nut with a new or serviceable part in accordance with the service bulletin. Thereafter, repeat the inspection (verification) specified in paragraph (a)(2) of this AD at intervals not to exceed 18 months. (B) If any damage or discrepancy of the tangential link upper bolt and washers is found, prior to further flight, replace the damaged or discrepant part with a new or serviceable part, and replace the bolt nut with a new or serviceable part, in accordance with the service bulletin. Thereafter, repeat the inspection (verification) specified in paragraph (a)(2) of this AD at intervals not to exceed 18 months. NEW REQUIREMENTS OF THIS AD: Replacement (b) Within 18 months after the effective date of this AD, accomplish the requirements of either paragraph (b)(1) or (b)(2) of this AD. Accomplishment of either paragraph (b)(1) or (b)(2) of this AD constitutes terminating action for the repetitive inspection requirements of this AD. (1) Replace the safety links on the aft engine mount with modified safety links in accordance with Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988. (2) Replace the tangential link upper bolt on the aft engine mount with a reworked bolt and a new nut retainer, in accordance with Parts 2 and 3 of Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999. Alternative Methods of Compliance (c) (1) 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, Seattle Aircraft Certification Office (ACO), 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, Seattle ACO. (2) Alternative methods of compliance, approved previously in accordance with AD 96-03-01 R1, amendment 39-9538, are approved as alternative methods of compliance with this AD. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (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. Incorporation by Reference (e) The actions shall be done in accordance with Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995; Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998; Boeing Service Bulletin 747-71A2277, Revision 2, dated January 14, 1999; Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988; as applicable. (1) The incorporation by reference of Boeing Service Bulletin 747-71A2277, Revision 2, dated January 14, 1999; Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988; as applicable is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, contains the following list of effective pages: Page Number Revision Level Shown on Page Date Shown on Page 1-5, 9, 10, 12 1 November 12, 1987 6-8, 11, 13-18 Original April 16, 1987 (2) The incorporation by reference of Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, was approved previously by the Director of the Federal Register as of February 16, 1996 (61 FR 10270, March 13, 1996). (3) 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, 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 November 8, 1999. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_99-20-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 99-20-09 Document Type: AD Final Rules Docket Number: 98-NM-277-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Tangential Link Upper Bolt Nut Status: Current Citation: (Federal Register: October 04, 1999 (Volume 64, Number 191)) Citation Publish Date: 10/04/1999 Effective Date: 02/16/1996 Make: The Boeing Company Model: 747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...Show more Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: 96-03-01 R1 Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 (64 FR 53621 No. 191 10/04/99) Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 99-20-09 CITATION: [Federal Register: October 04, 1999 (Volume 64, Number 191)] PAGE NUMBER: [Page 53621] DOCKET NUMBER: 98-NM-277-AD AMENDMENT: 39-11339 AD NUMBER: 99-20-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: Final rule SUMMARY: This amendment supersedes an existing airworthiness directive (AD), applicable to certain Boeing Model 747 series airplanes, that currently requires inspections of the lower engine mount to determine if the tangential link upper bolt and nut are oriented properly, and if the tangential link upper bolt nut is torqued within certain limits. Additionally, that amendment requires replacement of the bolt and nut with serviceable parts, if necessary, and requires certain follow-on actions for airplanes on which the upper bolt is missing. This amendment requires accomplishment of a previously optional terminating action or a new alternative terminating action for the repetitive inspections. This amendment is prompted by development of a new terminating action by the manufacturer. The actions specified by this AD are intended to prevent separation of the engine from the airplane due to migration of the tangential link upper bolt. DATES: Effective November 8, 1999. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of November 8, 1999. The incorporation by reference of Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, listed in the regulations, was approved previously by the Director of the Federal Register as of February 16, 1996 (61 FR 10270, March 13, 1996). ADDRESSES: The service information referenced in this AD may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. This information may be examined at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. FOR FURTHER INFORMATION CONTACT: Tamara L. Anderson, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Transport Airplane Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2771; fax (425) 227-1181. SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 96-03-01 R1, amendment 39-9538 (61 FR 10270, March 13, 1996), which is applicable to certain Boeing Model 747 series airplanes, was published in the Federal Register on July 16, 1999 (64 FR 38379). The action proposed to continue to require inspections of the lower engine mount to determine if the tangential link upper bolt and nut are oriented properly, and if the tangential link upper bolt nut is torqued within certain limits. Additionally, that action also proposed to continue to require replacement of the bolt and nut with serviceable parts, if necessary, and requires certain follow-on actions for airplanes on which the upper bolt is missing. That action also proposed to require accomplishment of either a previously optional terminating action or a new, alternative terminating action for the repetitive inspections. Comments Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received. The commenter supports the proposed rule. Conclusion After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed. Cost Impact There are approximately 421 airplanes of the affected design in the worldwide fleet. The FAA estimates that 185 airplanes of U.S. registry will be affected by this AD. The inspections that are currently required by AD 96-03-01 R1 take approximately 16 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $177,600, or $960 per airplane, per inspection cycle. The replacement of the safety link that is required as one option for compliance with this AD action will take approximately 18 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $30,228 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $31,308 per airplane. In lieu of replacement of the safety link, this AD provides for replacement of the tangential link upper bolt on the aft engine mount with a reworked bolt and a new nut retainer. Such replacement, which is provided as an additional option for compliance with this AD action, will take approximately 20 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts will cost approximately $1,888 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $3,088 per airplane. The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. Regulatory Impact The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES." List of Subjects in 14 CFR Part 39 Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. Adoption of the Amendment Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows: PART 39 - AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. Section 39.13 is amended by removing amendment 39-9538 (61 FR 10270, March 13, 1996), and by adding a new airworthiness directive (AD), amendment 39-11339, to read as follows: REGULATORY TEXT: 99-20-09 BOEING: Amendment 39-11339. Docket 98-NM-277-AD. Supersedes AD 96-03-01 R1, amendment 39-9538. Applicability: Model 747 series airplanes, as listed in Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995; or Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999; certificated in any category. NOTE 1: This AD applies to each airplane 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 airplanes 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 (c)(1) 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 separation of the engine from the airplane, accomplish the following: RESTATEMENT OF REQUIREMENTS OF AD 96-03-01 R1, AMENDMENT 39-9538: Inspections and Corrective Actions (a) Within 90 days after February 16, 1996 (the effective date of AD 96-03-01 R1, amendment 39-9538), accomplish the requirements of paragraphs (a)(1) and (a)(2) of this AD in accordance with Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, or Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999. (1) Perform a visual inspection to ensure that installation of the tangential link upper bolt nut is on the forward side of the engine mount fitting. (i) If the tangential link upper bolt nut is installed on the forward side of the engine mount fitting, repeat the visual inspection at intervals not to exceed 18 months. (ii) If the tangential link upper bolt nut is not installed on the forward side of the engine mount fitting, prior to further flight, remove the nut, bolt, and washers, and reinstall the nut, bolt, and washers in accordance with the service bulletin. Thereafter, repeat the visual inspection at intervals not to exceed 18 months. (iii) If the tangential link upper bolt is missing from the engine mount fitting, prior to further flight, perform the various follow-on actions in accordance with the service bulletin. (The follow-on actions include visual inspections, magnetic particle inspections, replacement of the lower engine mount fitting with a serviceable part, if necessary; installation of new safety links, bolts, and nuts; and installation of a new tangential link upper bolt.) Thereafter, repeat the visual inspection at intervals not to exceed 18 months. (2) Perform an inspection to verify that the torque value of the tangential link upper bolt (on both sides of the mount) is within the limits specified in the service bulletin. (i) If the torque value of the tangential link upper bolt nut is within the limits specified in the service bulletin, repeat the inspection (verification) at intervals not to exceed 18 months. (ii) If the torque value of the tangential link upper bolt nut is outside the limits specified in the service bulletin, prior to further flight, perform a visual inspection of the tangential link upper bolt and washer for any damage or discrepancy, in accordance with the service bulletin. (A) If no damage or discrepancy of the tangential link upper bolt and washers is found, prior to further flight, replace the bolt nut with a new or serviceable part in accordance with the service bulletin. Thereafter, repeat the inspection (verification) specified in paragraph (a)(2) of this AD at intervals not to exceed 18 months. (B) If any damage or discrepancy of the tangential link upper bolt and washers is found, prior to further flight, replace the damaged or discrepant part with a new or serviceable part, and replace the bolt nut with a new or serviceable part, in accordance with the service bulletin. Thereafter, repeat the inspection (verification) specified in paragraph (a)(2) of this AD at intervals not to exceed 18 months. NEW REQUIREMENTS OF THIS AD: Replacement (b) Within 18 months after the effective date of this AD, accomplish the requirements of either paragraph (b)(1) or (b)(2) of this AD. Accomplishment of either paragraph (b)(1) or (b)(2) of this AD constitutes terminating action for the repetitive inspection requirements of this AD. (1) Replace the safety links on the aft engine mount with modified safety links in accordance with Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988. (2) Replace the tangential link upper bolt on the aft engine mount with a reworked bolt and a new nut retainer, in accordance with Parts 2 and 3 of Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998, or Revision 2, dated January 14, 1999. Alternative Methods of Compliance (c) (1) 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, Seattle Aircraft Certification Office (ACO), 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, Seattle ACO. (2) Alternative methods of compliance, approved previously in accordance with AD 96-03-01 R1, amendment 39-9538, are approved as alternative methods of compliance with this AD. NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (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. Incorporation by Reference (e) The actions shall be done in accordance with Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995; Boeing Service Bulletin 747-71A2277, Revision 1, dated May 21, 1998; Boeing Service Bulletin 747-71A2277, Revision 2, dated January 14, 1999; Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988; as applicable. (1) The incorporation by reference of Boeing Service Bulletin 747-71A2277, Revision 2, dated January 14, 1999; Boeing Service Bulletin 747-71-2206, dated April 16, 1987; or Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, as revised by Boeing Notice of Status Change No. 747-71-2206 NSC 1, dated December 4, 1987, and Boeing Notice of Status Change No. 747-71-2206 NSC 2, dated March 17, 1988; as applicable is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Boeing Service Bulletin 747-71-2206, Revision 1, dated November 12, 1987, contains the following list of effective pages: Page Number Revision Level Shown on Page Date Shown on Page 1-5, 9, 10, 12 1 November 12, 1987 6-8, 11, 13-18 Original April 16, 1987 (2) The incorporation by reference of Boeing Alert Service Bulletin 747-71A2277, dated November 29, 1995, was approved previously by the Director of the Federal Register as of February 16, 1996 (61 FR 10270, March 13, 1996). (3) 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, 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 November 8, 1999. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
2025-09-08
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: Outboard elevators without balance weights could result in abnormal vibration, buffeting, flutter, or oscillation that could result in loss of continued safe flight and landing. Additionally, outbo...
2025-02-05
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: improper inner diameter grinding of landing gear outer cylinders, resulting in possible heat damage to the outer cylinder of the nose landing gear (NLG), body landing gear (BLG), and wing landing g...
2024-19-01 Recurring
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: cracks at eight fastener hole locations in the fuselage skin lap splice between stations (STAs) 1450 and 1470 at stringers S-23L and S-23R
2023-23-14
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: latent failures of the lightning protection features for the engine fuel feed system, which could result in the potential for ignition sources inside fuel tanks, leading to a fuel tank explosion an...