AD 75-07-08
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-58A | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58B | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58BT | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58C | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58D | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58DT | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58E | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58ET | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58F | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58FT | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58G | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58H | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58HT | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58J | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
| aircraft | Sikorsky Aircraft Corporation | S-58JT | Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D |
Unsafe Condition
Excessive stresses and possible structural failures in the tail rotor blades, tail rotor gear box assembly, and tail pylon area from tail rotor unbalance.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Lubricate and inspect the rotary assembly (P/N S1610-31100 series) and counterweight assembly (P/N S1610-34200 series) within 10 hours time in service after the effective date. Thereafter, repeat inspections every 50 hours or earlier if unbalance is suspected. If balance remains unchanged after two consecutive inspections, extend intervals to 100 hours. Unbalanced assemblies must be rebalanced or removed before further flight.
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
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Affected Aircraft
Sikorsky Models S-58 and S-58T series helicopters including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D equipped with S1610-31100 series rotary rudder assemblies and S1610-34200 series counterweight assembly.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_75-07-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type ...Show more Subject: Tail Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/08/1975 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: 75-07-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2138 AD NUMBER: 75-07-08 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D ACTION: SUMMARY: DATES: Effective April 8, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-08 SIKORSKY AIRCRAFT: Amendment 39-2138. Applies to Models S-58 and S-58T series helicopters certificted in all categories, including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH- 34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, VH- 34D, equipped with S1610-31100 series rotary rudder assemblies and S1610-34200 series counterweight assembly. Compliance required as indicated. To prevent excessive stresses and possible structural failures in the tail rotor blades, tail rotor gear box assembly, and tail pylon area, from tail rotor unbalance, accomplish the following: a. Within the next 10 hours time in service after the effective date of this AD unless already accomplished, lubricate and inspect the rotary assembly, P/N S1610-31100 series and counterweight assembly, P/N S1610-34200 series, for balance in accordance with Section 2, Paragraph A of Sikorsky Service Bulletin No. 58B15-14A, dated December 19, 1974, or later FAA approved revision. b. Thereafter, lubricate and inspect at intervals not to exceed 50 hours time in service from the last inspection, or earlier if unbalance is suspected, in accordance with Section 2, Paragraph B of Sikorsky Service Bulletin No. 58B15-14A or later FAA approved revision. c. If after two consecutive 50 hour repetitive inspections as specified in Paragraph b., the rotor balance remains unchanged, and within limits, these inspections can be extended to a 100 hour interval. These 100 hour intervals can be maintained if all subsequent 100 hour inspections show that rotor balance remains unchanged. d. Rotary rudder assemblies, P/N S1610-31100 series and counterweight assembly P/N S1610-34200 series which are not balanced as specified in Paragraphs a., b., and c must be either rebalanced or removed for corrective action in accordance with Section 2, Paragraphs A and B of Sikorsky Service Bulletin No. 58B15-14A or later FAA approved revision, before further flight. e. 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 of United Aircraft Corporation, Stratford, Connecticut 06602. These documents may also be examined at the Office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment becomes effective April 8, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_75-07-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 75-07-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type ...Show more Subject: Tail Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 04/08/1975 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: 75-07-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2138 AD NUMBER: 75-07-08 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-58 and S-58T Series Helicopters Including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH-34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, and VH-34D ACTION: SUMMARY: DATES: Effective April 8, 1975. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 75-07-08 SIKORSKY AIRCRAFT: Amendment 39-2138. Applies to Models S-58 and S-58T series helicopters certificted in all categories, including Military Type HSS-1, HSS-1F, HSS-1N, HUS-1, HUS-1A, HUS-1AN, HUS-1G, HUS-1Z, H-34A, H-34C, H-34J, CH-34A, CH- 34C, HH-34F, SH-34G, SH-34H, SH-34J, UH-34D, UH-34E, UH-34G, UH-34J, VH-34C, VH- 34D, equipped with S1610-31100 series rotary rudder assemblies and S1610-34200 series counterweight assembly. Compliance required as indicated. To prevent excessive stresses and possible structural failures in the tail rotor blades, tail rotor gear box assembly, and tail pylon area, from tail rotor unbalance, accomplish the following: a. Within the next 10 hours time in service after the effective date of this AD unless already accomplished, lubricate and inspect the rotary assembly, P/N S1610-31100 series and counterweight assembly, P/N S1610-34200 series, for balance in accordance with Section 2, Paragraph A of Sikorsky Service Bulletin No. 58B15-14A, dated December 19, 1974, or later FAA approved revision. b. Thereafter, lubricate and inspect at intervals not to exceed 50 hours time in service from the last inspection, or earlier if unbalance is suspected, in accordance with Section 2, Paragraph B of Sikorsky Service Bulletin No. 58B15-14A or later FAA approved revision. c. If after two consecutive 50 hour repetitive inspections as specified in Paragraph b., the rotor balance remains unchanged, and within limits, these inspections can be extended to a 100 hour interval. These 100 hour intervals can be maintained if all subsequent 100 hour inspections show that rotor balance remains unchanged. d. Rotary rudder assemblies, P/N S1610-31100 series and counterweight assembly P/N S1610-34200 series which are not balanced as specified in Paragraphs a., b., and c must be either rebalanced or removed for corrective action in accordance with Section 2, Paragraphs A and B of Sikorsky Service Bulletin No. 58B15-14A or later FAA approved revision, before further flight. e. 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 of United Aircraft Corporation, Stratford, Connecticut 06602. These documents may also be examined at the Office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. This amendment becomes effective April 8, 1975. FOOTER:
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