AD 75-26-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters |
Unsafe Condition
The unsafe condition involves the potential failure of S-61 helicopter components due to insufficient replacement schedules, as identified through an engineering evaluation program and additional substantiating data.
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Required Actions
Replace S-61 components in accordance with the schedule of Section 2C of Sikorsky Service Bulletin No. 61B General-1F dated October 20, 1975, or later FAA approved revisions.
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Compliance Time
After the effective date of this AD
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Affected Aircraft
Sikorsky Models S-61L, S-61N, and S-61NM helicopters certificated in all categories.
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Federal Register Abstract
Component Replacement
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-26-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-26-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters Subject: Component Replacement Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/02/1976 Make: Sikorsky Aircraft Corporation Model: S-61L | S-61N | S-61NM Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-26-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2461 AD NUMBER: 75-26-10 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters ACTION: SUMMARY: DATES: Effective January 2, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-26-10 SIKORSKY AIRCRAFT: Amendment 39-2461. Applies to S-61L, S-61N, and S-61NM helicopters certificated in all categories. Compliance required as indicated. As a result of the completion of a recent engineering evaluation program and the development of additional substantiating data, a new schedule of replacement times has been established for the components of S-61 helicopters. (a) After the effective date of this AD, the replacement of S-61 components must be accomplished in accordance with the schedule of Section 2C of Sikorsky Service Bulletin No. 61B General-1F dated October 20, 1975, or later FAA approved revisions. (b) 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 Sikorsky Aircraft, Stratford, Connecticut 06602. These documents may also be examined at FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its Headquarters in Washington, D.C., and at the FAA, New England Region, Burlington, Massachusetts. This supersedes Amendment 39-1167 (36 F.R. 4689), AD 71-06-02 as amended by Amendment 39-1271 (36 F.R. 16186), Amendment 39-1948 (39 F. R. 31626), and Amendment 39-1978 (39 F.R. 34649). This amendment becomes effective January 2, 1976. FOOTER:
Document Text
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AD Final Rules - DRS_75-26-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-26-10 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters Subject: Component Replacement Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/02/1976 Make: Sikorsky Aircraft Corporation Model: S-61L | S-61N | S-61NM Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 75-26-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2461 AD NUMBER: 75-26-10 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61L, S-61N, and S-61NM Helicopters ACTION: SUMMARY: DATES: Effective January 2, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-26-10 SIKORSKY AIRCRAFT: Amendment 39-2461. Applies to S-61L, S-61N, and S-61NM helicopters certificated in all categories. Compliance required as indicated. As a result of the completion of a recent engineering evaluation program and the development of additional substantiating data, a new schedule of replacement times has been established for the components of S-61 helicopters. (a) After the effective date of this AD, the replacement of S-61 components must be accomplished in accordance with the schedule of Section 2C of Sikorsky Service Bulletin No. 61B General-1F dated October 20, 1975, or later FAA approved revisions. (b) 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 Sikorsky Aircraft, Stratford, Connecticut 06602. These documents may also be examined at FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its Headquarters in Washington, D.C., and at the FAA, New England Region, Burlington, Massachusetts. This supersedes Amendment 39-1167 (36 F.R. 4689), AD 71-06-02 as amended by Amendment 39-1271 (36 F.R. 16186), Amendment 39-1948 (39 F. R. 31626), and Amendment 39-1978 (39 F.R. 34649). This amendment becomes effective January 2, 1976. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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