AD 86-23-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-100 Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-100B Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-100B SUD Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200B Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200C Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-200F Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-300 Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400 Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400D Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747-400F Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747SP Series | BOEING Model 747 Series Airplanes |
| aircraft | The Boeing Company | 747SR Series | BOEING Model 747 Series Airplanes |
Unsafe Condition
Separation of an engine due to failed H-11 bolts in the outboard attach fitting nacelle struts.
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Required Actions
Perform visual inspections of outboard and inboard attach fitting H-11 bolts for structural integrity per Boeing Service Bulletin 747-57A2235, replace failed bolts before further flight, and replace all remaining H-11 bolts with Inconel bolts within specified timeframes.
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Compliance Time
Prior to accumulation of 10,000 flight hours or within 100 landings after the effective date (12/01/1986), whichever occurs later for outboard inspections; prior to 10,000 flight hours or within 600 landings after effective date, whichever occurs later for inboard inspections. Outboard bolt replacement within 24 months after effective date; inboard within 48 months.
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Affected Aircraft
Boeing Model 747 series airplanes, line numbers 1 through 644.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Outboard Attach Fitting H-11 Bolts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-23-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-23-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 747 Series Airplanes Subject: Outboard Attach Fitting H-11 Bolts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/01/1986 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: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 86-23-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5450 AD NUMBER: 86-23-01 SUBJECT HEADING: BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective December 1, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-23-01 BOEING: Amendment 39-5450. Applies to all Model 747 series airplanes, certificated in any category, line numbers 1 through 644. To prevent separation of an engine due to failed H-11 bolts, accomplish the following, unless already accomplished: A. Prior to accumulation of 10,000 flight hours, or within 100 landings after the effective date of this AD, whichever occurs later, perform a visual inspection of the outboard attach fitting H-11 bolts of all nacelle struts for structural integrity to determine if any H-11 bolts have failed, in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. Repeat the inspections thereafter at intervals not to exceed 7-1/2 months. B. Prior to accumulation of 10,000 flight hours, or within 600 landings after the effective date of this AD, whichever occurs later, perform a visual inspection of the inboard attach fitting joints of all nacelle struts for structural integrity to determine if any H-11 bolts have failed, in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. Repeat the inspections thereafter at intervals not to exceed 15 months. C. Failed bolts must be replaced prior to further flight. D. Installation of the Inconel replacement bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions constitutes terminating action for the repetitive inspections required by paragraph A. and B., above. E. Within 24 months after the effective date of this AD, replace all remaining H-11 bolts on the outboard attach fitting of all nacelle struts with Inconel bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. F. Within 48 months after the effective date of this AD, replace all remaining H-11 bolts on the inboard attach fitting of all nacelle struts with Inconel bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. G. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. H. Special 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. I. For the H-11 bolts that utilized the BACN10HR162 nuts, the accomplishment of the inspection requirements of AD 86-05-11 (Amendment 39-5255) is considered an acceptable alternate means of compliance for the initial inspection requirements of paragraph A. and B. of this AD. NOTE: Inspections performed in accordance with Boeing Service Letter Number 747- SL-57-47, dated April 24, 1986, are considered equivalent to those performed in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986. All persons affected by this directive who have not already received the appropriate service document from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124-2207. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective December 1, 1986. FOOTER:
Document Text
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AD Final Rules - DRS_86-23-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-23-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: BOEING Model 747 Series Airplanes Subject: Outboard Attach Fitting H-11 Bolts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/01/1986 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: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 86-23-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5450 AD NUMBER: 86-23-01 SUBJECT HEADING: BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective December 1, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-23-01 BOEING: Amendment 39-5450. Applies to all Model 747 series airplanes, certificated in any category, line numbers 1 through 644. To prevent separation of an engine due to failed H-11 bolts, accomplish the following, unless already accomplished: A. Prior to accumulation of 10,000 flight hours, or within 100 landings after the effective date of this AD, whichever occurs later, perform a visual inspection of the outboard attach fitting H-11 bolts of all nacelle struts for structural integrity to determine if any H-11 bolts have failed, in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. Repeat the inspections thereafter at intervals not to exceed 7-1/2 months. B. Prior to accumulation of 10,000 flight hours, or within 600 landings after the effective date of this AD, whichever occurs later, perform a visual inspection of the inboard attach fitting joints of all nacelle struts for structural integrity to determine if any H-11 bolts have failed, in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. Repeat the inspections thereafter at intervals not to exceed 15 months. C. Failed bolts must be replaced prior to further flight. D. Installation of the Inconel replacement bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions constitutes terminating action for the repetitive inspections required by paragraph A. and B., above. E. Within 24 months after the effective date of this AD, replace all remaining H-11 bolts on the outboard attach fitting of all nacelle struts with Inconel bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. F. Within 48 months after the effective date of this AD, replace all remaining H-11 bolts on the inboard attach fitting of all nacelle struts with Inconel bolts in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986, or later FAA-approved revisions. G. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. H. Special 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. I. For the H-11 bolts that utilized the BACN10HR162 nuts, the accomplishment of the inspection requirements of AD 86-05-11 (Amendment 39-5255) is considered an acceptable alternate means of compliance for the initial inspection requirements of paragraph A. and B. of this AD. NOTE: Inspections performed in accordance with Boeing Service Letter Number 747- SL-57-47, dated April 24, 1986, are considered equivalent to those performed in accordance with Boeing Service Bulletin 747-57A2235, dated June 27, 1986. All persons affected by this directive who have not already received the appropriate service document from the manufacturer may obtain copies upon request to the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124-2207. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective December 1, 1986. FOOTER:
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Retrieved: Apr 8, 2026
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