AD 74-20-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61R | Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters |
Unsafe Condition
Loose or missing screws or cracks in the outboard end of the main rotor blades, including the tip cap and tip cap bracket, which could lead to blade failure.
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Required Actions
Inspect main rotor blades for loose/missing screws or cracks using specified service bulletin methods. Repair or replace blades with issues before further flight. Inspections must be done at intervals based on blade series and operating weight, with compliance required within specified hours time in service.
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Compliance Time
Compliance required as indicated in the AD, with inspections due within specific timeframes (e.g., 30, 50, 200 hours) after the effective date and at intervals thereafter.
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Affected Aircraft
Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM helicopters equipped with S6115-20501, S6115-20601, S6117-20101, or S6188-15001 series main rotor blades.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Blades
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-20-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-20-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters Subject: Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/25/1977 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61L | S-61N | S-61NM | S-61R 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: 74-20-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2829 AD NUMBER: 74-20-09 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters ACTION: SUMMARY: DATES: Effective February 25, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-20-09 SIKORSKY AIRCRAFT: Amendment 39-1972 as amended by Amendment 39-2034 is further amended by Amendment 39-2829. Applies to all Sikorsky S-61A, S-61L, S- 61N, S-61R and S-61NM helicopters certificated in all categories that are equipped with S6115- 20501 series, S6115-20601 series, S6117-20101 series and S6188-15001 series main rotor blades. Compliance required as indicated. To prevent operation with loose or missing screws, or with cracks in the outboard end of the main rotor blades, including the tip cap and tip cap bracket, accomplish the following: (a) Inspect main rotor blades that do not have tip cap bracket doubler P/N 61070- 15120 installed, and have less than 2,000 hours time in service on the effective date of this AD, for loose or missing screws or for cracks at the outboard end of the main rotor blade spar, tip cap, or tip cap bracket, in accordance with Section 2., paragraphs A and B., of Sikorsky Service Bulletin No. 61B15-9F, dated November 2, 1976 or later FAA approved revisions within the next 30 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 30 hours time in service from the last inspection. If screws are missing or loose, and cannot be secured, or if there is motion in the joint between the tip cap and the blade, or if cracks are found, replace the main rotor blade or repair it in accordance with Section 2., paragraph C., of the above service bulletin prior to further flight. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket, replace or repair the main rotor blade in accordance with Section 2., paragraph B., of the above service bulletin prior to further flight. (b) Inspect main rotor blades that do not have tip cap bracket doubler P/N 61070- 15120 installed, and have 2000 hours or more time in service on the effective date of this AD, for loose or missing screws or for cracks at the outboard end of the main rotor blade spar, tip cap, or tip cap bracket, in accordance with Section 2., paragraphs A and B, of the above Service Bulletin prior to the first flight of each day. If screws are missing or loose, and cannot be secured, or if there is motion in the joint between the tip cap and the blade, or if cracks are found, replace the main rotor blade or repair it in accordance with paragraph 2C of the above bulletin prior to further flight. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket replace or repair the main rotor blade, in accordance with Section 2., paragraph B., of the above service bulletin, prior to further flight. (c) Inspect main rotor blades that have tip cap bracket P/N 61070-15120 installed for cracks at the outboard end of the main rotor blade spar, tip cap, and tip cap bracket, in accordance with Section 2, paragraph B., of the above bulletin, within the next 50 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 50 hours time in service from the last inspection. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket, replace or repair the main rotor blade prior to further flight, in accordance with Section 2., paragraph B., of the above bulletin. (d) For helicopters operating at 19,500 pounds gross weight and below, inspect the outboard end of the main blades, series S6115-20501, series S6115-20601, series S6117-20101, and series S6188-15001, using the dye penetrant method, in accordance with Section 2., paragraph D., of the above Service Bulletin, within the next 200 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 200 hours time in service from the last inspection. If a crack is found, replace the main rotor blade prior to further flight. (e) For helicopters operating above a gross weight of 19,500 pounds, inspect the outboard end of the main rotor blades using the dye penetrant method, in accordance with Section 2., paragraph D., of the above Service Bulletin, within the next 50 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 50 hours time in service from the last inspection. If a crack is found, replace the main rotor blade prior to further flight. (f) Upon request of the operator, equivalent methods of compliance with the inspection and repair requirements of this AD may be approved by the Chief, Engineering and Manufacturing Branch, New England Region. Repetitive inspection intervals specified in this AD may be adjusted, by the Chief, Engineering and Manufacturing Branch, New England Region, to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. Amendment 39-1972 supersedes Amendment 39-1583 (38 F.R. 1501), AD 73-02-02. Amendment 39-1972 became effective October 4, 1974. Amendment 39-2034 became effective December 12, 1974. This Amendment 39-2829 becomes effective February 25, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_74-20-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-20-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters Subject: Main Rotor Blades Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/25/1977 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61L | S-61N | S-61NM | S-61R 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: 74-20-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2829 AD NUMBER: 74-20-09 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61A, S-61L, S-61N, S-61R, and S-61NM Helicopters ACTION: SUMMARY: DATES: Effective February 25, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-20-09 SIKORSKY AIRCRAFT: Amendment 39-1972 as amended by Amendment 39-2034 is further amended by Amendment 39-2829. Applies to all Sikorsky S-61A, S-61L, S- 61N, S-61R and S-61NM helicopters certificated in all categories that are equipped with S6115- 20501 series, S6115-20601 series, S6117-20101 series and S6188-15001 series main rotor blades. Compliance required as indicated. To prevent operation with loose or missing screws, or with cracks in the outboard end of the main rotor blades, including the tip cap and tip cap bracket, accomplish the following: (a) Inspect main rotor blades that do not have tip cap bracket doubler P/N 61070- 15120 installed, and have less than 2,000 hours time in service on the effective date of this AD, for loose or missing screws or for cracks at the outboard end of the main rotor blade spar, tip cap, or tip cap bracket, in accordance with Section 2., paragraphs A and B., of Sikorsky Service Bulletin No. 61B15-9F, dated November 2, 1976 or later FAA approved revisions within the next 30 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 30 hours time in service from the last inspection. If screws are missing or loose, and cannot be secured, or if there is motion in the joint between the tip cap and the blade, or if cracks are found, replace the main rotor blade or repair it in accordance with Section 2., paragraph C., of the above service bulletin prior to further flight. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket, replace or repair the main rotor blade in accordance with Section 2., paragraph B., of the above service bulletin prior to further flight. (b) Inspect main rotor blades that do not have tip cap bracket doubler P/N 61070- 15120 installed, and have 2000 hours or more time in service on the effective date of this AD, for loose or missing screws or for cracks at the outboard end of the main rotor blade spar, tip cap, or tip cap bracket, in accordance with Section 2., paragraphs A and B, of the above Service Bulletin prior to the first flight of each day. If screws are missing or loose, and cannot be secured, or if there is motion in the joint between the tip cap and the blade, or if cracks are found, replace the main rotor blade or repair it in accordance with paragraph 2C of the above bulletin prior to further flight. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket replace or repair the main rotor blade, in accordance with Section 2., paragraph B., of the above service bulletin, prior to further flight. (c) Inspect main rotor blades that have tip cap bracket P/N 61070-15120 installed for cracks at the outboard end of the main rotor blade spar, tip cap, and tip cap bracket, in accordance with Section 2, paragraph B., of the above bulletin, within the next 50 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 50 hours time in service from the last inspection. If a crack is found in the tip cap, tip cap attachment land, or tip cap bracket, replace or repair the main rotor blade prior to further flight, in accordance with Section 2., paragraph B., of the above bulletin. (d) For helicopters operating at 19,500 pounds gross weight and below, inspect the outboard end of the main blades, series S6115-20501, series S6115-20601, series S6117-20101, and series S6188-15001, using the dye penetrant method, in accordance with Section 2., paragraph D., of the above Service Bulletin, within the next 200 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 200 hours time in service from the last inspection. If a crack is found, replace the main rotor blade prior to further flight. (e) For helicopters operating above a gross weight of 19,500 pounds, inspect the outboard end of the main rotor blades using the dye penetrant method, in accordance with Section 2., paragraph D., of the above Service Bulletin, within the next 50 hours time in service after the effective date of this AD, unless already accomplished, and at intervals thereafter within 50 hours time in service from the last inspection. If a crack is found, replace the main rotor blade prior to further flight. (f) Upon request of the operator, equivalent methods of compliance with the inspection and repair requirements of this AD may be approved by the Chief, Engineering and Manufacturing Branch, New England Region. Repetitive inspection intervals specified in this AD may be adjusted, by the Chief, Engineering and Manufacturing Branch, New England Region, to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. Amendment 39-1972 supersedes Amendment 39-1583 (38 F.R. 1501), AD 73-02-02. Amendment 39-1972 became effective October 4, 1974. Amendment 39-2034 became effective December 12, 1974. This Amendment 39-2829 becomes effective February 25, 1977. FOOTER:
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