AD 91-20-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 737-300 Series | Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes |
| aircraft | The Boeing Company | 737-400 Series | Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes |
| aircraft | The Boeing Company | 737-500 Series | Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes |
Unsafe Condition
Uncommanded stabilizer movement in the static position due to potential failure of the stabilizer trim jackscrew actuator and auxiliary brake assembly.
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Required Actions
Remove the existing stabilizer trim jackscrew actuator and replace it with a modified stabilizer trim assembly having a redesigned auxiliary brake assembly per Boeing Service Bulletin 737-27-1161. An alternative method of compliance may be used if approved by the FAA Manager, Seattle Aircraft Certification Office.
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Compliance Time
within 36 months after the effective date of this AD
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Affected Aircraft
Boeing Model 737-300, -400, and -500 series airplanes listed in Boeing Service Bulletin 737-27-1161, dated November 1, 1990.
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Federal Register Abstract
Stabilizer Trim Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-20-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-20-04 Document Type: AD Final Rules Docket Number: 91-NM-38-AD Subject Heading: Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes Subject: Stabilizer Trim Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/07/1991 Make: The Boeing Company Model: 737-300 Series | 737-400 Series | 737-500 Series Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 91-20-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-38-AD AMENDMENT: 39-8038 AD NUMBER: 91-20-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes ACTION: SUMMARY: DATES: Effective November 7, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 1-20-04 BOEING: Amendment 39-8038. Docket No. 91-NM-38-AD. Applicability: Boeing Model 737-300, -400, and -500 series airplanes, as listed in Boeing Service Bulletin 737-27-1161, dated November 1, 1990, certificated in any category. Compliance: Required within 36 months after the effective date of this AD, unless previously accomplished. To prevent uncommanded stabilizer movement in the static position, accomplish the following: (a) Remove the existing stabilizer trim jackscrew actuator and replace it with a stabilizer trim assembly that has been modified with the redesigned auxiliary brake assembly in accordance with Boeing Service Bulletin 737-27-1161, dated November 1, 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. (d) The replacement requirements shall be done in accordance with Boeing Service Bulletin 737-27-1161, dated November 1, 1990. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, D.C. This amendment (39-8038, AD 91-20-04) becomes effective on November 7, 1991. FOOTER:
Document Text
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AD Final Rules - DRS_91-20-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-20-04 Document Type: AD Final Rules Docket Number: 91-NM-38-AD Subject Heading: Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes Subject: Stabilizer Trim Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/07/1991 Make: The Boeing Company Model: 737-300 Series | 737-400 Series | 737-500 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: 91-20-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-38-AD AMENDMENT: 39-8038 AD NUMBER: 91-20-04 SUBJECT HEADING: Airworthiness Directives; BOEING Model 737-300, -400, and -500 Series Airplanes ACTION: SUMMARY: DATES: Effective November 7, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 1-20-04 BOEING: Amendment 39-8038. Docket No. 91-NM-38-AD. Applicability: Boeing Model 737-300, -400, and -500 series airplanes, as listed in Boeing Service Bulletin 737-27-1161, dated November 1, 1990, certificated in any category. Compliance: Required within 36 months after the effective date of this AD, unless previously accomplished. To prevent uncommanded stabilizer movement in the static position, accomplish the following: (a) Remove the existing stabilizer trim jackscrew actuator and replace it with a stabilizer trim assembly that has been modified with the redesigned auxiliary brake assembly in accordance with Boeing Service Bulletin 737-27-1161, dated November 1, 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. (d) The replacement requirements shall be done in accordance with Boeing Service Bulletin 737-27-1161, dated November 1, 1990. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, D.C. This amendment (39-8038, AD 91-20-04) becomes effective on November 7, 1991. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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