AD 88-04-09
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
Failure of the pneumatic system 8th stage check valve could cause engine or pneumatic system damage.
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Required Actions
Inspect the pneumatic system 8th stage check valves on both engines within 6 months after the effective date. If valves are identified by serial number as requiring further inspection, remove them, inspect the valve retention collar, and modify as necessary prior to further flight. Valves not installed must be inspected and modified prior to installation.
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Compliance Time
within the next 6 months after the effective date of this AD
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Affected Aircraft
Boeing Model 767 series airplanes listed in Boeing Service Bulletin 767-36-0021, dated September 17, 1987, certificated in any category.
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Federal Register Abstract
Pneumatic System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_88-04-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 88-04-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BOEING Model 767 Series Airplanes Subject: Pneumatic System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/05/1988 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767-200 Series | 767-300 Series | 767-300F Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 88-04-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5854 AD NUMBER: 88-04-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 767 Series Airplanes ACTION: SUMMARY: DATES: Effective April 5, 1988. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 88-04-09 BOEING: Amendment 39-5854. Applies to Model 767 series airplanes, as listed in Boeing Service Bulletin 767-36-0021, dated September 17, 1987, certificated in any category. Compliance required within the next six months after the effective date of this AD, unless already accomplished. To preclude engine or pneumatic system damage caused by failure of the pneumatic system 8th stage check valve, accomplish the following: A. Within the next 6 months after the effective date of this AD, inspect the pneumatic system 8th stage check valves on both engines, in accordance with Boeing Service Bulletin 767-36-0021, dated September 17, 1987, or later FAA-approved revision, to determine if the serial numbers are among those listed in Hamilton Standard Service Bulletin 36-2056, dated June 29, 1987, or later FAA-approved revision, as requiring further inspection. B. If any valve is identified by serial number as requiring further inspection, prior to further flight, remove the valve from the airplane, inspect the valve retention collar and, if necessary, modify the valve in accordance with the above mentioned service bulletins. C. Valves not installed on an airplane must be inspected, and modified if necessary, in accordance with the above-mentioned service bulletins, prior to their installation on airplanes. D. An alternate means of compliance or adjustment of the compliance time, which provide an acceptable level of safety, and which has the concurrence of an FAA Principal Maintenance Inspector, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the rework required by 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 the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124-2207. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective April 5, 1988. FOOTER:
Document Text
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AD Final Rules - DRS_88-04-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 88-04-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BOEING Model 767 Series Airplanes Subject: Pneumatic System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/05/1988 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: 88-04-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5854 AD NUMBER: 88-04-09 SUBJECT HEADING: Airworthiness Directives; BOEING Model 767 Series Airplanes ACTION: SUMMARY: DATES: Effective April 5, 1988. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 88-04-09 BOEING: Amendment 39-5854. Applies to Model 767 series airplanes, as listed in Boeing Service Bulletin 767-36-0021, dated September 17, 1987, certificated in any category. Compliance required within the next six months after the effective date of this AD, unless already accomplished. To preclude engine or pneumatic system damage caused by failure of the pneumatic system 8th stage check valve, accomplish the following: A. Within the next 6 months after the effective date of this AD, inspect the pneumatic system 8th stage check valves on both engines, in accordance with Boeing Service Bulletin 767-36-0021, dated September 17, 1987, or later FAA-approved revision, to determine if the serial numbers are among those listed in Hamilton Standard Service Bulletin 36-2056, dated June 29, 1987, or later FAA-approved revision, as requiring further inspection. B. If any valve is identified by serial number as requiring further inspection, prior to further flight, remove the valve from the airplane, inspect the valve retention collar and, if necessary, modify the valve in accordance with the above mentioned service bulletins. C. Valves not installed on an airplane must be inspected, and modified if necessary, in accordance with the above-mentioned service bulletins, prior to their installation on airplanes. D. An alternate means of compliance or adjustment of the compliance time, which provide an acceptable level of safety, and which has the concurrence of an FAA Principal Maintenance Inspector, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the rework required by 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 the Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124-2207. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective April 5, 1988. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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