AD 91-06-03
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
Cracking of the Section 42 fuselage frame web at the stringer cutout from body station 540 to BS 920, Stringer 8L to S-8R could result in sudden cabin pressure loss.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform a detailed visual inspection for cracks of the Section 42 fuselage frame web within the next 500 flight cycles after the effective date or prior to 12,000 total flight cycles, whichever is later. Repeat inspections at intervals not exceeding 3,000 flight cycles. If cracking is found, repair the frame web per Boeing SRM Section 53-10-04, Figures 4 or 35, or an approved method before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 500 flight cycles after the effective date of this AD, or prior to the accumulation of 12,000 total flight cycles, whichever occurs later
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Boeing Model 747 series airplanes, line numbers 001 through 045, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Fuselage Frame Web
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-06-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-06-03 Document Type: AD Final Rules Docket Number: 90-NM-152-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Fuselage Frame Web Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/08/1991 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: 91-06-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-152-AD AMENDMENT: 39-6923 AD NUMBER: 91-06-03 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective April 8, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-06-03 BOEING: Amendment 39-6923. Docket No. 90-NM-152-AD. Applicability: Model 747 series airplanes, line numbers 001 through 045, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent sudden cabin pressure loss, accomplish the following: A. Within the next 500 flight cycles after the effective date of this AD, or prior to the accumulation of 12,000 total flight cycles, whichever occurs later, perform a detailed visual inspection for cracks of the Section 42 fuselage frame web at the stringer cutout from body station (BS) 540 to BS 920, Stringer (S) 8L to S-8R. Repeat this inspection thereafter at intervals not to exceed 3,000 flight cycles. B. If cracking is found as the result of the inspections required by paragraph A. of this AD, prior to further flight, repair the fuselage frame web in accordance with the Boeing 747 Structural Repair Manual (SRM), Section 53-10-04, Figure 4 or Figure 35; or in a manner approved by the Manager, Seattle Aircraft Certification Office, FAA, Transport Airplane Directorate. C. 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 (ACO), Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Seattle ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Seattle ACO. D. 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 SW., Renton, Washington. This amendment (39-6923, AD 91-06-03) becomes effective on April 8, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-06-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-06-03 Document Type: AD Final Rules Docket Number: 90-NM-152-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Fuselage Frame Web Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/08/1991 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: 91-06-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-152-AD AMENDMENT: 39-6923 AD NUMBER: 91-06-03 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective April 8, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-06-03 BOEING: Amendment 39-6923. Docket No. 90-NM-152-AD. Applicability: Model 747 series airplanes, line numbers 001 through 045, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent sudden cabin pressure loss, accomplish the following: A. Within the next 500 flight cycles after the effective date of this AD, or prior to the accumulation of 12,000 total flight cycles, whichever occurs later, perform a detailed visual inspection for cracks of the Section 42 fuselage frame web at the stringer cutout from body station (BS) 540 to BS 920, Stringer (S) 8L to S-8R. Repeat this inspection thereafter at intervals not to exceed 3,000 flight cycles. B. If cracking is found as the result of the inspections required by paragraph A. of this AD, prior to further flight, repair the fuselage frame web in accordance with the Boeing 747 Structural Repair Manual (SRM), Section 53-10-04, Figure 4 or Figure 35; or in a manner approved by the Manager, Seattle Aircraft Certification Office, FAA, Transport Airplane Directorate. C. 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 (ACO), Transport Airplane Directorate. NOTE: The request should be submitted directly to the Manager, Seattle ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Seattle ACO. D. 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 SW., Renton, Washington. This amendment (39-6923, AD 91-06-03) becomes effective on April 8, 1991. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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