AD 76-05-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Hamilton Sundstrand | 54H | HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers |
| propeller | Hamilton Sundstrand | 54H | HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers |
Unsafe Condition
Wear of pitchlock regulator extension sleeve threads resulting in looseness and possible separation of the extension sleeve from the pitchlock regulator.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Check torque required to turn the extension sleeve P/N 541850, Rev. C or later in a clockwise direction per Hamilton Standard Service Bulletin HS Code 54H60 No. A 73, Rev. 1 or equivalent. If running torque is less than 100 ft. lbs., remove and inspect threads for wear; remove worn sleeves. Return regulator to service if torque does not reach 130 ft. lbs.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 200 hours time in service after the effective date of this AD, unless already accomplished within the last 1800 hours time in service, and thereafter at intervals not to exceed 2000 hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Hamilton Standard Models 54H60-63, -81, -91, -111, -117 and -125 Propellers.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Pitchlock Regulator Extension Sleeve Threads
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_76-05-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-05-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers Subject: Pitchlock Regulator Extension Sleeve Threads Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/17/1976 Make: Hamilton Sundstrand Model: 54H Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 76-05-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2537 AD NUMBER: 76-05-06 SUBJECT HEADING: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers ACTION: SUMMARY: DATES: Effective March 17, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-05-06 HAMILTON STANDARD: Amendment 39-2537. Applies to propeller Models 54H60-63, -81, -91, -111, -117 and -125. Compliance required within the next 200 hours time in service after the effective date of this AD, unless already accomplished within the last 1800 hours time in service, and thereafter at intervals not to exceed 2000 hours. To prevent wear of pitchlock regulator extension sleeve threads resulting in looseness and possible separation of the extension sleeve from the pitchlock regulator accomplish the following: Check the torque required to turn the extension sleeve, P/N 541850, Rev. C or later revision, in a clockwise (tightening direction), in accordance with Hamilton Standard Service Bulletin HS Code 54H60 No. A 73, Rev. 1 dated January 2, 1976 or later revision or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. (a) If a running torque is not obtained up to a maximum applied static torque of 130 ft. lb., return pitchlock regulator to service. (b) If the running torque required to turn the extension sleeve is less than 100 ft. lbs., remove extension sleeve and inspect threads for wear. Remove from service extension sleeves with worn threads. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Hamilton Standard, Division of United Technologies Corporation, Windsor Locks, Connecticut 06096. These documents may also be examined at the office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment becomes effective on March 17, 1976. FOOTER:
Document Text
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AD Final Rules - DRS_76-05-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-05-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers Subject: Pitchlock Regulator Extension Sleeve Threads Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/17/1976 Make: Hamilton Sundstrand Model: 54H Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 76-05-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2537 AD NUMBER: 76-05-06 SUBJECT HEADING: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117 and -125 Propellers ACTION: SUMMARY: DATES: Effective March 17, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-05-06 HAMILTON STANDARD: Amendment 39-2537. Applies to propeller Models 54H60-63, -81, -91, -111, -117 and -125. Compliance required within the next 200 hours time in service after the effective date of this AD, unless already accomplished within the last 1800 hours time in service, and thereafter at intervals not to exceed 2000 hours. To prevent wear of pitchlock regulator extension sleeve threads resulting in looseness and possible separation of the extension sleeve from the pitchlock regulator accomplish the following: Check the torque required to turn the extension sleeve, P/N 541850, Rev. C or later revision, in a clockwise (tightening direction), in accordance with Hamilton Standard Service Bulletin HS Code 54H60 No. A 73, Rev. 1 dated January 2, 1976 or later revision or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. (a) If a running torque is not obtained up to a maximum applied static torque of 130 ft. lb., return pitchlock regulator to service. (b) If the running torque required to turn the extension sleeve is less than 100 ft. lbs., remove extension sleeve and inspect threads for wear. Remove from service extension sleeves with worn threads. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Hamilton Standard, Division of United Technologies Corporation, Windsor Locks, Connecticut 06096. These documents may also be examined at the office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment becomes effective on March 17, 1976. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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