AD 91-21-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Airbus SAS | BAC 1-11 200 Series | Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes |
| aircraft | Airbus SAS | BAC 1-11 400 Series | Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes |
Unsafe Condition
Cracks in the left and right machined attachment angles (Part Number AB27-7761/2) and cracks in the top flange of the longitudinal boom of the left and right outboard auxiliary beam could degrade the structural capabilities of the pressure cabin.
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Required Actions
Perform dye penetrant inspections on attachment angles and visual inspections on auxiliary beams per specified service bulletin paragraphs. Replace or repair cracked structure before further flight. Replace attachment angles with new parts prior to 85,000 landings since new. Comply with service bulletin 53-A-PM5991 for all actions.
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Compliance Time
For airplanes operating at 7.5 psi: at or prior to 33,000 landings or within 4,000 landings after 11/19/1991, whichever is later, then every 8,000 landings. For those at 8.2 psi: at or prior to 22,000 landings or within 3,000 landings after 11/19/1991, whichever is later, then every 5,000 landings. Attachment angles must be replaced before 85,000 landings since new and every 85,000 landings thereafter.
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Affected Aircraft
British Aerospace Model BAC 1-11 200 and 400 series airplanes, certificated in any category.
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Federal Register Abstract
Inspect For Cracks
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-21-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-21-04 Document Type: AD Final Rules Docket Number: 91-NM-26-AD Subject Heading: Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes Subject: Inspect For Cracks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1991 Make: Airbus SAS Model: BAC 1-11 200 Series | BAC 1-11 400 Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-21-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-26-AD AMENDMENT: 39-8051 AD NUMBER: 91-21-04 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes ACTION: SUMMARY: DATES: Effective on November 19, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-21-04 BRITISH AEROSPACE: Amendment 39-8051. Docket No. 91-NM-26-AD. Applicability: Model BAC 1-11 200 and 400 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent degradation in the structural capabilities of the pressure cabin on affected airplanes, accomplish the following: A. For airplanes operating at a maximum cabin differential pressure of 7.5 pounds per square inch (psi), as specified in British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990: At or prior to the accumulation of 33,000 landings or within 4,000 landings after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 8,000 landings, accomplish the following: 1. Perform a dye penetrant inspection to detect cracks in the left and right machined attachment angles, Part Number AB27-7761/2, in accordance with paragraph 2.1.3 of the service bulletin. 2. Perform a visual inspection to detect cracks in the top flange of the longitudinal boom of the left and right outboard auxiliary beam, in accordance with paragraph 2.1.4 of the service bulletin. B. For airplanes operating at a cabin pressure in excess of 7.5 psi up to a maximum of 8.2 psi, as specified in British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990: At or prior to the accumulation of 22,000 landings or within 3,000 landings after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 5,000 landings, accomplish the following: 1. Perform a dye penetrant inspection to detect cracks in the left and right machined attachment angles, Part Number AB27-7761/2, in accordance with paragraph 2.2.3 of the service bulletin. 2. Perform a visual inspection to detect cracks in the top flange of the longitudinal boom of the left and right outboard auxiliary beam, in accordance with paragraph 2.2.4 of the service bulletin. C. If defects are found during the inspections required by this AD, prior to further flight, either replace the cracked structure with serviceable parts of the same part number; or repair in accordance with a method approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region. Following repair or replacement, repeat the inspections required by paragraphs A. and B. of this AD at the specified intervals. D. All machined attachment angles having Part Number AB27-7761/2 must be replaced with a new part of the same part number prior to the accumulation of 85,000 landings since new and thereafter at intervals not to exceed 85,000 landings. E. An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. F. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. G. The inspection, repair, and replacement requirements shall be done in accordance with British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990. 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 British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041-0414. 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. This amendment (39-8051, AD 91-21-04) becomes effective on November 19, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-21-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-21-04 Document Type: AD Final Rules Docket Number: 91-NM-26-AD Subject Heading: Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes Subject: Inspect For Cracks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/19/1991 Make: Airbus SAS Model: BAC 1-11 200 Series | BAC 1-11 400 Series 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: 91-21-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-26-AD AMENDMENT: 39-8051 AD NUMBER: 91-21-04 SUBJECT HEADING: Airworthiness Directives; British Aerospace Model BAC 1-11 200 and 400 Series Airplanes ACTION: SUMMARY: DATES: Effective on November 19, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-21-04 BRITISH AEROSPACE: Amendment 39-8051. Docket No. 91-NM-26-AD. Applicability: Model BAC 1-11 200 and 400 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent degradation in the structural capabilities of the pressure cabin on affected airplanes, accomplish the following: A. For airplanes operating at a maximum cabin differential pressure of 7.5 pounds per square inch (psi), as specified in British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990: At or prior to the accumulation of 33,000 landings or within 4,000 landings after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 8,000 landings, accomplish the following: 1. Perform a dye penetrant inspection to detect cracks in the left and right machined attachment angles, Part Number AB27-7761/2, in accordance with paragraph 2.1.3 of the service bulletin. 2. Perform a visual inspection to detect cracks in the top flange of the longitudinal boom of the left and right outboard auxiliary beam, in accordance with paragraph 2.1.4 of the service bulletin. B. For airplanes operating at a cabin pressure in excess of 7.5 psi up to a maximum of 8.2 psi, as specified in British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990: At or prior to the accumulation of 22,000 landings or within 3,000 landings after the effective date of this AD, whichever occurs later, and thereafter at intervals not to exceed 5,000 landings, accomplish the following: 1. Perform a dye penetrant inspection to detect cracks in the left and right machined attachment angles, Part Number AB27-7761/2, in accordance with paragraph 2.2.3 of the service bulletin. 2. Perform a visual inspection to detect cracks in the top flange of the longitudinal boom of the left and right outboard auxiliary beam, in accordance with paragraph 2.2.4 of the service bulletin. C. If defects are found during the inspections required by this AD, prior to further flight, either replace the cracked structure with serviceable parts of the same part number; or repair in accordance with a method approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region. Following repair or replacement, repeat the inspections required by paragraphs A. and B. of this AD at the specified intervals. D. All machined attachment angles having Part Number AB27-7761/2 must be replaced with a new part of the same part number prior to the accumulation of 85,000 landings since new and thereafter at intervals not to exceed 85,000 landings. E. An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113. F. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. G. The inspection, repair, and replacement requirements shall be done in accordance with British Aerospace Alert Service Bulletin 53-A-PM5991, Issue 1, dated September 5, 1990. 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 British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041-0414. 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. This amendment (39-8051, AD 91-21-04) becomes effective on November 19, 1991. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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