AD 90-26-04
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
Loss of airplane primary flight controls due to loss of hydraulic fluid from all four hydraulic systems.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the hydraulic lines in the elevator control system in accordance with Section III of the Accomplishment Instructions, Steps G through H, of Boeing Alert Service Bulletin 747-29A2063, Revision 5, dated June 7, 1990. An alternate means of compliance or adjustment of compliance time may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 4,500 hours time-in-service after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Model 747 series airplanes, line numbers 1 through 39, certificated in any category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Elevator Control System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-26-04 Document Type: AD Final Rules Docket Number: 90-NM-135-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/15/1991 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: 90-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-135-AD AMENDMENT: 39-6830 AD NUMBER: 90-26-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective January 15, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-26-04 BOEING: Amendment 39-6830. Docket No. 90-NM-135-AD. Applicability: Model 747 series airplanes, line numbers 1 through 39, certificated in any category. Compliance: Required within the next 4,500 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the loss of the airplane primary flight controls due to loss of hydraulic fluid from all four hydraulic systems, accomplish the following: A. Modify the hydraulic lines in the elevator control system in accordance with Section III of the Accomplishment Instructions, Steps G through H, of Boeing Alert Service Bulletin 747-29A2063, Revision 5, dated June 7, 1990. B. 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), FAA, 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. 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 (39-6830, AD 90-26-04) becomes effective on January 15, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_90-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-26-04 Document Type: AD Final Rules Docket Number: 90-NM-135-AD Subject Heading: Airworthiness Directives; BOEING Model 747 Series Airplanes Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/15/1991 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: 90-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-135-AD AMENDMENT: 39-6830 AD NUMBER: 90-26-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 747 Series Airplanes ACTION: SUMMARY: DATES: Effective January 15, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-26-04 BOEING: Amendment 39-6830. Docket No. 90-NM-135-AD. Applicability: Model 747 series airplanes, line numbers 1 through 39, certificated in any category. Compliance: Required within the next 4,500 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the loss of the airplane primary flight controls due to loss of hydraulic fluid from all four hydraulic systems, accomplish the following: A. Modify the hydraulic lines in the elevator control system in accordance with Section III of the Accomplishment Instructions, Steps G through H, of Boeing Alert Service Bulletin 747-29A2063, Revision 5, dated June 7, 1990. B. 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), FAA, 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. 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 (39-6830, AD 90-26-04) becomes effective on January 15, 1991. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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