AD 59-16-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-58A | Airworthiness Directives; Sikorsky Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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 Model S-58 Helicopters including Military Types 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
Torque cannot be maintained on the damper trunnion bolt, leading to fretting and fatiguing of the bolt.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
During the 50-hour periodic inspection, remove the damper trunnion bolt (P/N S1610-23198) and inspect for wearing, scouring, or fretting. Replace the bolt prior to further flight if any indications are found.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
During the 50-hour periodic inspection
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Model S-58 helicopters including military types 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, except those modified with Sikorsky Modification Kit P/N S1607-5695-1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Damper Trunnion Bolt
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_59-16-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-16-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-58 Helicopters including Military Types HSS-1, HSS-1F, HS...Show more Subject: Damper Trunnion Bolt 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: 59-16-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2140 AD NUMBER: 59-16-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-58 Helicopters including Military Types 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: 59-16-04 SIKORSKY: Amendment 34 (24 F.R. 6581) as amended by Amendment 39-2140. Applies to all model S-58 helicopters including military types 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, except for those modified in accordance with Sikorsky Modification Kit, P/N S1607-5695-1. Compliance required as indicated. Due to the present design of the damper trunnion assembly, torque cannot be maintained on the bolt, thereby leading to fretting and fatiguing of the bolt. Although this problem has been partially corrected by replacing the AN 177-34 bolt with S1610-23198 bolt (NAS 627-48 bolt with cotter pin hole), working of the bolt in the assembly has not been completely eliminated. Accordingly, it is considered essential that close surveillance be maintained and the following inspection be carried out pending the development and installation of a redesigned trunnion assembly to correct this difficulty. During the 50-hour periodic inspection of the damper trunnion for freedom per item No. 20(c) of the Periodic Inspection Check Sheet, Airframe System S-58 Maintenance Manual, remove the damper trunnion bolt P/N S1610-23198 and inspect for condition. If indications of wearing, scouring or fretting are found the bolt must be replaced prior to further flight. This amendment 39-2140 becomes effective April 8, 1975. FOOTER:
Document Text
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AD Final Rules - DRS_59-16-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 59-16-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-58 Helicopters including Military Types HSS-1, HSS-1F, HS...Show more Subject: Damper Trunnion Bolt 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: 59-16-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2140 AD NUMBER: 59-16-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-58 Helicopters including Military Types 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: 59-16-04 SIKORSKY: Amendment 34 (24 F.R. 6581) as amended by Amendment 39-2140. Applies to all model S-58 helicopters including military types 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, except for those modified in accordance with Sikorsky Modification Kit, P/N S1607-5695-1. Compliance required as indicated. Due to the present design of the damper trunnion assembly, torque cannot be maintained on the bolt, thereby leading to fretting and fatiguing of the bolt. Although this problem has been partially corrected by replacing the AN 177-34 bolt with S1610-23198 bolt (NAS 627-48 bolt with cotter pin hole), working of the bolt in the assembly has not been completely eliminated. Accordingly, it is considered essential that close surveillance be maintained and the following inspection be carried out pending the development and installation of a redesigned trunnion assembly to correct this difficulty. During the 50-hour periodic inspection of the damper trunnion for freedom per item No. 20(c) of the Periodic Inspection Check Sheet, Airframe System S-58 Maintenance Manual, remove the damper trunnion bolt P/N S1610-23198 and inspect for condition. If indications of wearing, scouring or fretting are found the bolt must be replaced prior to further flight. This amendment 39-2140 becomes effective April 8, 1975. FOOTER:
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