AD 75-03-05
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
Inflight separation of the extension sleeve, P/N 541850, Change B or earlier revision, from the pitch lock regulator assembly resulting in propeller pitchlocking.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the fluid transfer housing extension sleeve with P/N 541850C or later revision, or modify per Hamilton Standard Service Bulletin HS Code 54H60, No. 59, Revision No. 1, or later FAA approved revision. Replace surge valve housing P/N 543734B or earlier with P/N 543734C or later, or replace P/N 535299E or earlier with P/N 535299F or later.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 100 hours time in service for propellers with 2500 or more hours as of effective date or unknown time, prior to 2600 hours total time in service for those with less than 2500 hours.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Hamilton Sundstrand 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
Pitch Lock Regulatory Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-03-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-03-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117, and -125 Propellers Subject: Pitch Lock Regulatory Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/05/1975 Make: Hamilton Sundstrand Model: 54H Product Type: Propeller Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-03-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2025 AD NUMBER: 75-03-05 SUBJECT HEADING: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117, and -125 Propellers ACTION: SUMMARY: DATES: Effective February 5, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-03-05 HAMILTON STANDARD: Amendment 39-2025. Applies to propeller Models 54H60-63, -81, -91, -111, -117, and -125. Compliance required as indicated, unless already accomplished. To prevent inflight separation of the extension sleeve, P/N 541850, Change B or earlier revision, from the pitch lock regulator assembly resulting in propeller pitchlocking, accomplish the following: A. Propellers with a total of 2500 or more hours in service as of the effective date of this AD or whose total time in service is unknown, accomplish the requirements of Paragraph (C) below within the next 100 hours time in service. B. Propellers with less than 2500 hours total time in service as of the effective date of this AD, accomplish the requirements of Paragraph (C) below prior to the accumulation of 2600 hours total time in service. C. 1. Replace the fluid transfer housing extension sleeve, P/N 541850B or earlier revision, with an extension sleeve, P/N 541850C or later revision, or with a modified extension sleeve in accordance with Hamilton Standard Service Bulletin HS Code 54H60, No. 59, Revision No. 1, dated August 1, 1972, or later FAA approved revision, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. 2. Replace the surge valve housing, P/N 543734B or earlier revision, with housing P/N 543734C or later revision, or replace surge valve housing, P/N 535299E or earlier revision with housing P/N 535299F or later revision. 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 Aircraft 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 February 5, 1975. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_75-03-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-03-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117, and -125 Propellers Subject: Pitch Lock Regulatory Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/05/1975 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: 75-03-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2025 AD NUMBER: 75-03-05 SUBJECT HEADING: HAMILTON STANDARD Models 54H60-63, -81, -91, -111, -117, and -125 Propellers ACTION: SUMMARY: DATES: Effective February 5, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-03-05 HAMILTON STANDARD: Amendment 39-2025. Applies to propeller Models 54H60-63, -81, -91, -111, -117, and -125. Compliance required as indicated, unless already accomplished. To prevent inflight separation of the extension sleeve, P/N 541850, Change B or earlier revision, from the pitch lock regulator assembly resulting in propeller pitchlocking, accomplish the following: A. Propellers with a total of 2500 or more hours in service as of the effective date of this AD or whose total time in service is unknown, accomplish the requirements of Paragraph (C) below within the next 100 hours time in service. B. Propellers with less than 2500 hours total time in service as of the effective date of this AD, accomplish the requirements of Paragraph (C) below prior to the accumulation of 2600 hours total time in service. C. 1. Replace the fluid transfer housing extension sleeve, P/N 541850B or earlier revision, with an extension sleeve, P/N 541850C or later revision, or with a modified extension sleeve in accordance with Hamilton Standard Service Bulletin HS Code 54H60, No. 59, Revision No. 1, dated August 1, 1972, or later FAA approved revision, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. 2. Replace the surge valve housing, P/N 543734B or earlier revision, with housing P/N 543734C or later revision, or replace surge valve housing, P/N 535299E or earlier revision with housing P/N 535299F or later revision. 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 Aircraft 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 February 5, 1975. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
2022-08-10 Recurring
final ruleAirworthiness Directives; Hamilton Sundstrand Corporation Propellers
Unsafe Condition: The separation of a 54H60 model propeller blade installed on a USMCR KC-130T airplane during a flight in July 2017, resulting in the loss of the airplane and 17 fatalities, revealed that 54H60 mode...
98-24-34
final ruleAirworthiness Directives; Hamilton Standard 54H60 Series Propellers
Unsafe Condition: Propeller blade cracks due to incomplete cold rolling during manufacture in the beveled radius area of the blade flange, which can result in blade separation and damage to the aircraft.
97-13-07
final ruleHamilton Standard 54H60 Series Propellers
Unsafe Condition: Propeller blade fracture due to a manufacturing defect in the beveled radius of the blade root, which could result in blade separation and loss of control of the aircraft.
86-01-07
final ruleHAMILTON STANDARD Models 54H60-77, -81, -123, -125, -131, and -133 Propellers
Unsafe Condition: Loss of aircraft control and possible loss of aircraft due to slippage of the valve housing cover input gear when less than 36 pounds of load is applied.