AD 68-19-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61D | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61E | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61R | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61V | Airworthiness Directives; Sikorsky Model S-61 Series helicopters |
Unsafe Condition
Failure of the main rotor blade spindle due to being salvaged or having accumulated 3000 or more hours' time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove and replace main rotor blade spindles with specified part numbers if salvaged or exceeding 3000 hours' time in service. Replace non-salvaged spindles before accumulating 3000 hours' time in service. Remove specific serial numbered spindles before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight or before the accumulation of 3000 hours' time in service as applicable.
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Affected Aircraft
Sikorsky Model S-61A, S-61D, S-61E, S-61L, S-61N, S-61NM, S-61R, S-61V helicopters with main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Rotor Blade Spindles
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-19-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-19-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-61 Series helicopters Subject: Rotor Blade Spindles Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/23/1975 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61D | S-61E | S-61L | S-61N | S-61NM | S-61R | S-61V 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: 68-19-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2450 AD NUMBER: 68-19-07 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-61 Series helicopters ACTION: SUMMARY: DATES: Effective December 23, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-19-07 SIKORSKY: Amendment 39-657 as amended by Amendment 39-2450. Applies to S-61 Series helicopters. Compliance required as indicated. To preclude the possibility of failure of the main rotor blade spindle, accomplish the following: (a) Before further flight, remove main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1 that either have been "salvaged" in accordance with procedures set forth in paragraph entitled "Salvage of Spindle" contained in Sikorsky Aircraft Overhaul Manual for the pertinent helicopter model, or have accumulated 3000 or more hours' time in service on the effective date of this AD, and replace with blade spindles of the same part number that have not been "salvaged" and that have less than 3000 hours' time in service. (b) Replace main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1, that have not been "salvaged" and have less than 3000 hours' time in service on the effective date of this AD, before the accumulation of 3000 hours' time in service with main rotor blades spindles of the same part number that have not been "salvaged" and have less than 3000 hours' time in service. (c) Before further flight, remove from service main rotor blade spindles P/N's S6110-23325-1, S6110-2325-2, and S6112-23025-1, serial numbers AX51, AX54, F2148, F2444, F2485, F2207, F1406, F1416, F1415, F1399, B-35, and F2451. Amendment 39-657 was effective September 27, 1968. This amendment 39-2450 becomes effective December 23, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_68-19-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-19-07 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-61 Series helicopters Subject: Rotor Blade Spindles Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/23/1975 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61D | S-61E | S-61L | S-61N | S-61NM | S-61R | S-61V 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: 68-19-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2450 AD NUMBER: 68-19-07 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-61 Series helicopters ACTION: SUMMARY: DATES: Effective December 23, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-19-07 SIKORSKY: Amendment 39-657 as amended by Amendment 39-2450. Applies to S-61 Series helicopters. Compliance required as indicated. To preclude the possibility of failure of the main rotor blade spindle, accomplish the following: (a) Before further flight, remove main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1 that either have been "salvaged" in accordance with procedures set forth in paragraph entitled "Salvage of Spindle" contained in Sikorsky Aircraft Overhaul Manual for the pertinent helicopter model, or have accumulated 3000 or more hours' time in service on the effective date of this AD, and replace with blade spindles of the same part number that have not been "salvaged" and that have less than 3000 hours' time in service. (b) Replace main rotor blade spindles P/Ns S6110-23325-1, S6110-23325-2, and S6112-23025-1, that have not been "salvaged" and have less than 3000 hours' time in service on the effective date of this AD, before the accumulation of 3000 hours' time in service with main rotor blades spindles of the same part number that have not been "salvaged" and have less than 3000 hours' time in service. (c) Before further flight, remove from service main rotor blade spindles P/N's S6110-23325-1, S6110-2325-2, and S6112-23025-1, serial numbers AX51, AX54, F2148, F2444, F2485, F2207, F1406, F1416, F1415, F1399, B-35, and F2451. Amendment 39-657 was effective September 27, 1968. This amendment 39-2450 becomes effective December 23, 1975. FOOTER:
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Retrieved: Apr 8, 2026
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