AD 89-07-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61D | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61E | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61NM | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61R | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61V | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters |
Unsafe Condition
Failure of the main rotor gearbox helical gear Part Number S6135-20620-003 with specified serial numbers could occur.
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Required Actions
Inspect the main rotor gearbox to identify the helical gear serial number. Replace the gear if its serial number is listed in this AD with an airworthy one having a different serial number. Ferrying is allowed under FAR Sections 21.197 and 21.199.
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Compliance Time
within the next 100 hours' time in service
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Affected Aircraft
Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, S-61L, S-61N, S-61NM, S-61R, S-61V helicopters equipped with main rotor gearbox helical gear Part Number S6135-20620-003, serial numbers 1086, 1087, 1089, 1090-1099, 1101, 1103-1113, 1116, 1117, 1130, 1132.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Gearbox
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_89-07-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-07-09 Document Type: AD Final Rules Docket Number: 89-ASW-4 Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters Subject: Main Rotor Gearbox Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/20/1989 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: 89-07-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-ASW-4 AMENDMENT: 39-6172 AD NUMBER: 89-07-09 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters ACTION: SUMMARY: DATES: Effective April 20, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-07-09 SIKORSKY AIRCRAFT: Amendment 39-6172. Applicability: All Model S-61 series helicopters, certificated in any category, equipped with main rotor gearbox helical gear Part Number S6135-20620-003, Serial Numbers 1086, 1087, 1089, and 1090 through and including 1099, 1101, 1103, through and including 1113, 1116, 1117, 1130, 1132. (Docket No. 89-ASW-4). Compliance: Required within the next 100 hours' time in service, unless already accomplished. To prevent possible failure of the helical gear, accomplish the following: (a) Inspect the main rotor gearbox to identify the serial number of the helical gear installed. If the helical gear is identified with a serial number listed in this AD, replace it with an airworthy helical gear which has a serial number other than listed in this AD. NOTE: Sikorsky Aircraft message CBT-TS-89-002 dated January 23, 1989, applies to this AD. (b) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the provisions of the AD can be accomplished. (c) An alternate means of compliance or an adjustment of the initial compliance time which provides an equivalent level of safety may be used if approved by the Manager, Boston Aircraft Certification Office, Federal Aviation Administration, 12 New England Executive Park, Burlington, MA 01803. The noted service information may be obtained from Sikorsky Aircraft, 6900 Main Street, Mail Stop S409A, Stratford, CT 06601-1381. This amendment (39-6172, AD 89-07-09) becomes effective on April 20, 1989. FOOTER:
Document Text
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AD Final Rules - DRS_89-07-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-07-09 Document Type: AD Final Rules Docket Number: 89-ASW-4 Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters Subject: Main Rotor Gearbox Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/20/1989 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: 89-07-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-ASW-4 AMENDMENT: 39-6172 AD NUMBER: 89-07-09 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Helicopters ACTION: SUMMARY: DATES: Effective April 20, 1989. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-07-09 SIKORSKY AIRCRAFT: Amendment 39-6172. Applicability: All Model S-61 series helicopters, certificated in any category, equipped with main rotor gearbox helical gear Part Number S6135-20620-003, Serial Numbers 1086, 1087, 1089, and 1090 through and including 1099, 1101, 1103, through and including 1113, 1116, 1117, 1130, 1132. (Docket No. 89-ASW-4). Compliance: Required within the next 100 hours' time in service, unless already accomplished. To prevent possible failure of the helical gear, accomplish the following: (a) Inspect the main rotor gearbox to identify the serial number of the helical gear installed. If the helical gear is identified with a serial number listed in this AD, replace it with an airworthy helical gear which has a serial number other than listed in this AD. NOTE: Sikorsky Aircraft message CBT-TS-89-002 dated January 23, 1989, applies to this AD. (b) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the provisions of the AD can be accomplished. (c) An alternate means of compliance or an adjustment of the initial compliance time which provides an equivalent level of safety may be used if approved by the Manager, Boston Aircraft Certification Office, Federal Aviation Administration, 12 New England Executive Park, Burlington, MA 01803. The noted service information may be obtained from Sikorsky Aircraft, 6900 Main Street, Mail Stop S409A, Stratford, CT 06601-1381. This amendment (39-6172, AD 89-07-09) becomes effective on April 20, 1989. FOOTER:
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