AD 91-10-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 767-200 Series | Airworthiness Directives; BOEING Model 767 Series Airplanes |
| aircraft | The Boeing Company | 767-300 Series | Airworthiness Directives; BOEING Model 767 Series Airplanes |
| aircraft | The Boeing Company | 767-300F Series | Airworthiness Directives; BOEING Model 767 Series Airplanes |
Unsafe Condition
Structural failure of the vertical stabilizer from overpressurization in the event of a rupture of the fuselage under the dorsal fin.
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Required Actions
Install a cover plate and a panel assembly over the lightening and access holes in the vertical stabilizer forward closure rib in accordance with Boeing Alert Service Bulletin 767-55A0007 or Revision 1. An alternative method of compliance may be used if approved by the Manager, Seattle Aircraft Certification Office.
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Compliance Time
Within the next 18 months after the effective date of this amendment
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Affected Aircraft
BOEING Model 767 series airplanes, line number 300 through 307, certificated in any category.
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Federal Register Abstract
Vertical Stabilizer
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-10-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-10-09 Document Type: AD Final Rules Docket Number: 90-NM-238-AD Subject Heading: Airworthiness Directives; BOEING Model 767 Series Airplanes Subject: Vertical Stabilizer Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/17/1991 Make: The Boeing Company Model: 767-200 Series | 767-300 Series | 767-300F Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-10-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-238-AD AMENDMENT: 39-6993 AD NUMBER: 91-10-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 767 Series Airplanes ACTION: SUMMARY: DATES: Effective June 17, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-10-09 BOEING: Amendment 39-6993. Docket No. 90-NM-238-AD. Applicability: Model 767 series airplanes, line number 300 through 307, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent structural failure of the vertical stabilizer from overpressurization in the event of a rupture of the fuselage under the dorsal fin, accomplish the following: A. Within the next 18 months after the effective date of this amendment, install a cover plate and a panel assembly over the lightening and access holes in the vertical stabilizer forward closure rib, in accordance with Boeing Alert Service Bulletin 767-55A0007, dated June 22, 1989, or Revision 1, dated May 24, 1990. B. 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, Seattle Aircraft Certification Office (ACO), 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, Seattle ACO. C. 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. All 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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6993, AD 91-10-09) becomes effective on June 17, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-10-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-10-09 Document Type: AD Final Rules Docket Number: 90-NM-238-AD Subject Heading: Airworthiness Directives; BOEING Model 767 Series Airplanes Subject: Vertical Stabilizer Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/17/1991 Make: The Boeing Company Model: 767-200 Series | 767-300 Series | 767-300F 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: 91-10-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-238-AD AMENDMENT: 39-6993 AD NUMBER: 91-10-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 767 Series Airplanes ACTION: SUMMARY: DATES: Effective June 17, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-10-09 BOEING: Amendment 39-6993. Docket No. 90-NM-238-AD. Applicability: Model 767 series airplanes, line number 300 through 307, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent structural failure of the vertical stabilizer from overpressurization in the event of a rupture of the fuselage under the dorsal fin, accomplish the following: A. Within the next 18 months after the effective date of this amendment, install a cover plate and a panel assembly over the lightening and access holes in the vertical stabilizer forward closure rib, in accordance with Boeing Alert Service Bulletin 767-55A0007, dated June 22, 1989, or Revision 1, dated May 24, 1990. B. 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, Seattle Aircraft Certification Office (ACO), 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, Seattle ACO. C. 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. All 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 Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. This amendment (39-6993, AD 91-10-09) becomes effective on June 17, 1991. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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