AD 89-23-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 757-200 Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 757-200CB Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 757-200PF Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 757-300 Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 767-200 Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 767-300 Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
| aircraft | The Boeing Company | 767-300F Series | Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes |
Unsafe Condition
Possible complete loss of hydraulic power due to potential failure of the Ram Air Turbine (RAT) hydraulic pump when the RAT Ground Checkout Module (GCM) is not properly reworked or replaced.
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Required Actions
Remove and rework or replace the RAT Ground Checkout Module (GCM) per applicable Boeing Service Bulletins. Inspect the downstream filter screen of the removed GCM before returning to service. If the screen is damaged, missing, or previously not inspected, test or replace the RAT hydraulic pump prior to further flight. Replace the pump if it is damaged during testing.
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Compliance Time
within the next 6,000 hours time-in-service after the effective date of this AD
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Affected Aircraft
Boeing Model 757 and 767 series airplanes listed in Boeing Alert Service Bulletins 757-29A0037, Revision 1, and 767-29A0035, Revision 1, both dated November 23, 1988.
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Federal Register Abstract
Ram Air Turbine
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_89-23-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-23-02 Document Type: AD Final Rules Docket Number: 89-NM-100-AD Subject Heading: Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes Subject: Ram Air Turbine Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/01/1989 Make: The Boeing Company Model: 757-200 Series | 757-200CB Series | 757-200PF Series | 757-300 Series | 767-200 Series | 767-300 Ser...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: 89-23-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-100-AD AMENDMENT: 39-6373 AD NUMBER: 89-23-02 SUBJECT HEADING: Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes ACTION: SUMMARY: DATES: Effective December 1, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-23-02 BOEING: Amendment 39-6373. Docket No. 89-NM-100-AD. Applicability: Model 757 and 767 series airplanes, as listed in Boeing Alert Service Bulletins 757-29A0037, Revision 1, and 767-29A0035, Revision 1, both dated November 23, 1988, certificated in any category. Compliance: Required within the next 6,000 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the possible complete loss of hydraulic power, accomplish the following: A. Remove and rework or replace the Ram Air Turbine (RAT) Ground Checkout Module (GCM) in accordance with Boeing Service Bulletin 757-29A0037, Revision 1, dated November 23, 1988, or Revision 2, dated August 3, 1989 (for Model 757 airplanes); or Boeing Service Bulletin 767-29A0035, Revision 1, dated November 23, 1989, or Revision 2, dated August 3, 1989 (for Model 767 airplanes); as appropriate. Prior to returning the airplane to service: 1. If the RAT has been operated or tested since the airplane delivery, prior to returning the airplane to service, inspect the downstream filter screen of the removed GCM. 2. If the screen is damaged or missing, or if GCM has been removed previously without inspecting the screen, prior to further flight, either test the RAT hydraulic pump or replace it in accordance with the applicable service bulletins. 3. If the RAT hydraulic pump is tested and found to be damaged, prior to further flight, replace it with a serviceable pump in accordance with the applicable service bulletin. 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, FAA, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment, and then send it to the Manager, Seattle Aircraft Certification Office. 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 Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment (39-6373, AD 89-23-02) becomes effective on December 1, 1989. FOOTER:
Document Text
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AD Final Rules - DRS_89-23-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-23-02 Document Type: AD Final Rules Docket Number: 89-NM-100-AD Subject Heading: Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes Subject: Ram Air Turbine Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/01/1989 Make: The Boeing Company Model: 757-200 Series | 757-200CB Series | 757-200PF Series | 757-300 Series | 767-200 Series | 767-300 Ser...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: 89-23-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-100-AD AMENDMENT: 39-6373 AD NUMBER: 89-23-02 SUBJECT HEADING: Airworthiness Directives; BOEING Model 757 and 767 Series Airplanes ACTION: SUMMARY: DATES: Effective December 1, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-23-02 BOEING: Amendment 39-6373. Docket No. 89-NM-100-AD. Applicability: Model 757 and 767 series airplanes, as listed in Boeing Alert Service Bulletins 757-29A0037, Revision 1, and 767-29A0035, Revision 1, both dated November 23, 1988, certificated in any category. Compliance: Required within the next 6,000 hours time-in-service after the effective date of this AD, unless previously accomplished. To prevent the possible complete loss of hydraulic power, accomplish the following: A. Remove and rework or replace the Ram Air Turbine (RAT) Ground Checkout Module (GCM) in accordance with Boeing Service Bulletin 757-29A0037, Revision 1, dated November 23, 1988, or Revision 2, dated August 3, 1989 (for Model 757 airplanes); or Boeing Service Bulletin 767-29A0035, Revision 1, dated November 23, 1989, or Revision 2, dated August 3, 1989 (for Model 767 airplanes); as appropriate. Prior to returning the airplane to service: 1. If the RAT has been operated or tested since the airplane delivery, prior to returning the airplane to service, inspect the downstream filter screen of the removed GCM. 2. If the screen is damaged or missing, or if GCM has been removed previously without inspecting the screen, prior to further flight, either test the RAT hydraulic pump or replace it in accordance with the applicable service bulletins. 3. If the RAT hydraulic pump is tested and found to be damaged, prior to further flight, replace it with a serviceable pump in accordance with the applicable service bulletin. 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, FAA, Northwest Mountain Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment, and then send it to the Manager, Seattle Aircraft Certification Office. 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 Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment (39-6373, AD 89-23-02) becomes effective on December 1, 1989. FOOTER:
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