AD 85-17-08
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-58A | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58B | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58BT | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58C | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58D | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58DT | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58E | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58ET | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58F | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58FT | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58G | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58H | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58HT | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58J | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-58JT | Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters |
Unsafe Condition
Separation of the stationary star and rotating star in the main rotor head star assembly due to damaged or loose retainer bolts (Part Number MS20074-04-04 or AN74A4).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 10 hours time in service after the AD's effective date, visually inspect the 12 main rotor head star assembly retainer bolts for damage and security. If damaged or loose bolts are found, perform fluorescent magnetic particle inspection for cracks and visually inspect threads for defects. Replace cracked or thread-damaged bolts with new zero-time bolts before further flight. Within 100 hours time in service, replace all 12 bolts with new zero-time bolts if not done in last 1,000 hours; thereafter, replace every 1,100 hours. Crush removed bolts to render unairworthy.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 10 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 25 hours time in service from the last inspection. Additionally, within the next 100 hours time in service after the effective date, unless already accomplished within the last 1,000 hours time in service; thereafter, install new bolts at intervals not to exceed 1,100 hours time in service.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT helicopters in any category and CH-34, HH-34, SH-34, UH-34, VH-34 series helicopters in restricted category.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Head Bolts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_85-17-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 85-17-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT,...Show more Subject: Main Rotor Head Bolts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/13/1986 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: 85-17-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5196 AD NUMBER: 85-17-08 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters ACTION: SUMMARY: DATES: Effective January 13, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 85-17-08 SIKORSKY AIRCRAFT: Amendment 39-5196. Applies to Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT helicopters certificated in any category and CH- 34 series HH-34 series, SH-34 series, UH-34 series, and VH-34 series helicopters certificated in the restricted category. Compliance is required as indicated, unless already accomplished. To prevent the separation of the stationary star and rotating star, accomplish the following: (a) Within the next 10 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 25 hours time in service from the last inspection, visually inspect the 12 main rotor head star assembly retainer bolts, Part Number lP/N) MS20074-04-04 or P/N AN74A4, for damage and for security of fastening in accordance with Section 2, Paragraph A, of Sikorsky Alert Service Bulletin (ASB) No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (b) If damaged or loose bolts are found, fluorescent magnetic particle inspect the bolts for cracks and visually inspect the bolt threads for crossed, stripped, or flattened threads in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (c) If a cracked bolt is found, or if the bolt threads are crossed, stripped, or flattened, replace with a new (zero time) bolt prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (d) Within the next 100 hours time in service after the effective date of this AD, unless already accomplished within the last 1,000 hours time in service, replace the 12 main rotor head star assembly retainer bolts with new (zero time) bolts in accordance with Section 2, Paragraphs A(7)(c), (d), and (e) and Paragraph B, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision; thereafter, install new (zero time) main rotor head star assembly retainer bolts at intervals not to exceed 1,100 hours time in service. (e) Render unairworthy any bolts removed in accordance with the requirements of paragraph (d) of this AD by crushing the threads. (f) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished. (g) An alternate method of compliance or adjustments of the compliance time which provide an equivalent level of safety may be used when approved by the Manager, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone number (617) 273-7118. 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 Division, United Technology Corporation, North Main Street, Stratford, Connecticut 06601. These documents also may be examined at the Rules Docket, Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106. This amendment becomes effective January 13, 1986, as to all persons except those persons to whom it was made immediately effective by priority letter AD No. 85-17-08, issued August 30, 1985, which contained this amendment. FOOTER:
Document Text
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AD Final Rules - DRS_85-17-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 85-17-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT,...Show more Subject: Main Rotor Head Bolts Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/13/1986 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: 85-17-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5196 AD NUMBER: 85-17-08 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, JT, CH- 34, HH-34, SH-34, UH-34, and VH-34 Series Helicopters ACTION: SUMMARY: DATES: Effective January 13, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 85-17-08 SIKORSKY AIRCRAFT: Amendment 39-5196. Applies to Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT helicopters certificated in any category and CH- 34 series HH-34 series, SH-34 series, UH-34 series, and VH-34 series helicopters certificated in the restricted category. Compliance is required as indicated, unless already accomplished. To prevent the separation of the stationary star and rotating star, accomplish the following: (a) Within the next 10 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 25 hours time in service from the last inspection, visually inspect the 12 main rotor head star assembly retainer bolts, Part Number lP/N) MS20074-04-04 or P/N AN74A4, for damage and for security of fastening in accordance with Section 2, Paragraph A, of Sikorsky Alert Service Bulletin (ASB) No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (b) If damaged or loose bolts are found, fluorescent magnetic particle inspect the bolts for cracks and visually inspect the bolt threads for crossed, stripped, or flattened threads in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (c) If a cracked bolt is found, or if the bolt threads are crossed, stripped, or flattened, replace with a new (zero time) bolt prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision. (d) Within the next 100 hours time in service after the effective date of this AD, unless already accomplished within the last 1,000 hours time in service, replace the 12 main rotor head star assembly retainer bolts with new (zero time) bolts in accordance with Section 2, Paragraphs A(7)(c), (d), and (e) and Paragraph B, of Sikorsky ASB No. 58B10-19, dated May 31, 1985, or later FAA-approved revision; thereafter, install new (zero time) main rotor head star assembly retainer bolts at intervals not to exceed 1,100 hours time in service. (e) Render unairworthy any bolts removed in accordance with the requirements of paragraph (d) of this AD by crushing the threads. (f) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished. (g) An alternate method of compliance or adjustments of the compliance time which provide an equivalent level of safety may be used when approved by the Manager, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone number (617) 273-7118. 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 Division, United Technology Corporation, North Main Street, Stratford, Connecticut 06601. These documents also may be examined at the Rules Docket, Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106. This amendment becomes effective January 13, 1986, as to all persons except those persons to whom it was made immediately effective by priority letter AD No. 85-17-08, issued August 30, 1985, which contained this amendment. FOOTER:
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