AD 66-19-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-58A | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58B | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58BT | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58C | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58D | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58DT | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58E | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58ET | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58F | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58FT | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58G | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58H | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58HT | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58J | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58JT | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61D | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61E | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61R | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61V | Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters |
Unsafe Condition
Tail rotor blades with flex shank area of the spar having less than minimum hardness requirements.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect S 1615-30100, S 6115-30001, and S 6117-30001 series tail rotor blades as per Sikorsky Service Bulletin 58B15-6A or 61B15-5A. Remove from service blades not meeting minimum hardness requirements before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 50 hours' time in service after the effective date of this AD unless already accomplished
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Models S-58 and S-61 Series Helicopters equipped with tail rotor blades with serial numbers listed in Sikorsky Service Bulletin 58B15-6A or 61B15-5A.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-19-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-19-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters Subject: Tail Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/14/1966 Make: Sikorsky Aircraft Corporation Model: S-58A | S-58B | S-58BT | S-58C | S-58D | S-58DT | S-58E | S-58ET | S-58F | S-58FT | S-58G | S-58H | ...Show more 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: 66-19-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-269 AD NUMBER: 66-19-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters ACTION: SUMMARY: DATES: Effective August 14, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-19-04 SIKORSKY: Amdt. 39-269 Part 39 Federal Register August 4, 1966. Applies to Models S-58 and S-61 Series Helicopters Equipped With Tail Rotor Blades With Serial Numbers Listed in the Appendix of Sikorsky Service Bulletin 58B15-6A, Dated May 18, 1966, or 61B15-5A, Dated May 18, 1966, As Applicable. Compliance required within the next 50 hours' time in service after the effective date of this AD unless already accomplished. To prevent operation with tail rotor blades of less than minimum hardness in the flex shank area of the spar, accomplish the following: (a) Inspect S 1615-30100, S 6115-30001, and S 6117-30001 Series tail rotor blades in the manner set forth in Sikorsky Service Bulletin 58B15-6A or 61B15-5A as applicable. (b) Before further flight, remove from service blades that do not meet the minimum hardness requirements for the flex shank area of the spar specified in the applicable Service Bulletin. This directive effective August 14, 1966. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_66-19-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-19-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters Subject: Tail Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/14/1966 Make: Sikorsky Aircraft Corporation Model: S-58A | S-58B | S-58BT | S-58C | S-58D | S-58DT | S-58E | S-58ET | S-58F | S-58FT | S-58G | S-58H | ...Show more 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: 66-19-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-269 AD NUMBER: 66-19-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-58 and S-61 Series Helicopters ACTION: SUMMARY: DATES: Effective August 14, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-19-04 SIKORSKY: Amdt. 39-269 Part 39 Federal Register August 4, 1966. Applies to Models S-58 and S-61 Series Helicopters Equipped With Tail Rotor Blades With Serial Numbers Listed in the Appendix of Sikorsky Service Bulletin 58B15-6A, Dated May 18, 1966, or 61B15-5A, Dated May 18, 1966, As Applicable. Compliance required within the next 50 hours' time in service after the effective date of this AD unless already accomplished. To prevent operation with tail rotor blades of less than minimum hardness in the flex shank area of the spar, accomplish the following: (a) Inspect S 1615-30100, S 6115-30001, and S 6117-30001 Series tail rotor blades in the manner set forth in Sikorsky Service Bulletin 58B15-6A or 61B15-5A as applicable. (b) Before further flight, remove from service blades that do not meet the minimum hardness requirements for the flex shank area of the spar specified in the applicable Service Bulletin. This directive effective August 14, 1966. FOOTER:
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Retrieved: Apr 8, 2026
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