AD 86-25-05
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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and 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, and JT, CH-34, HH-34, SH-34, UH- 34, and VH-34 Series Helicopters |
Unsafe Condition
Failure of tail rotor intermediate gearbox input bevel pinions Part Number S1635-64114-0 or output bevel gears Part Number S1635-64115-0.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace pinions or gears with serviceable parts prior to reaching specified time-in-service limits. For pinions/gears with ≤750 hours by AD effective date, replace before 1,000 hours. For those >750 hours, replace within next 250 hours. Use rotorcraft hours if individual records are unavailable.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Prior to accumulation of 1,000 hours' time in service (for ≤750 hours at effective date) or within next 250 hours' time in service (for >750 hours at effective date).
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, CH-34, HH-34, SH-34, UH-34, and VH-34 series helicopters with tail rotor intermediate gearbox using P/N S1635-64114-0 pinions and P/N S1635-64115-0 gears, excluding exempt combinations listed in Note 1.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Gearbox Pinions Or Gears
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-25-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-25-05 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: Gearbox Pinions Or Gears Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/05/1987 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: 86-25-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5471 AD NUMBER: 86-25-05 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT, CH-34, HH-34, SH-34, UH- 34, and VH-34 Series Helicopters ACTION: SUMMARY: DATES: Effective January 5, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-25-05 SIKORSKY AIRCRAFT: Amendment 39-5471. Applies to Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT, CH-34 series, HH-34 series, SH-34 series, UH- 34 series, and VH-34 series helicopters certificated in any category and fitted with tail rotor intermediate gearbox input bevel pinions Part Number (P/N) S1635-64114-0 and output bevel gears P/N S1635-64115-0. (See Note 1 for exempt pinion and gear configurations.) Compliance is required as indicated, unless already accomplished. (a) To preclude failure of pinions or gears identified above, accomplish the following: (1) For applicable pinions or gears that have attained 750 or less hours' time in service on the effective date of this AD, replace with a serviceable pinion or gear as required, prior to their accumulation of 1,000 hours' time in service. (2) For pinions or gears that have attained more than 750 hours' time in service on the effective date of this AD, replace with a serviceable pinion or gear as required, within the next 250 hours' time in service. (3) Operators who have not kept records of hours' time in service on individual intermediate gearbox bevel gears and bevel pinions shall substitute rotorcraft hours' time in service in lieu thereof. NOTE 1. This AD is not applicable to helicopters fitted with tail rotor intermediate gears which utilize the following pinion and gear combinations: (a) P/N 1635-64114-101 pinion and P/N S1635-64115-101 gear. (b) P/N 1635-64114-102 pinion and P/N S1635-64115-102 gear. (c) P/N 1635-64114-0 pinion and P/N S1635-64115-0 gear reworked in accordance with Sikorsky Service Bulletin 58B35-26. This rework includes remarking P/N S1635-64114-0 pinion and P/N S1635-64115-0 gear with TS-200-1 and TS-200-2, respectively. NOTE 2. Refer to the Equalized Inspection and Maintenance Program Manual SA 4047-20, Revision 10, dated December 14, 1984, or later FAA-approved revision for retirement times assigned to new or modified bevel pinions and bevel gears for the Model S-58BT, DT, ET, FT, HT, and JT helicopters, and to the Maintenance Manual SA 4045-15 Section IV, revised December 14, 1984, or later FAA-approved revision for retirement times assigned to new or modified bevel pinions and gears for the Model S-58A, B, C, D, E, F, G, H, and J helicopters. Upon request, an alternate method of compliance which provides an equivalent level of safety may be approved by the Manager, Boston Aircraft Certification Office, ANE-150, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803. Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, Boston Aircraft Certification Office, ANE-150, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803 may adjust the compliance time specified in this AD. This amendment becomes effective on January 5, 1987. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_86-25-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-25-05 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: Gearbox Pinions Or Gears Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/05/1987 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: 86-25-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5471 AD NUMBER: 86-25-05 SUBJECT HEADING: Airworthiness Directives; SIKORSKY AIRCRAFT Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT, CH-34, HH-34, SH-34, UH- 34, and VH-34 Series Helicopters ACTION: SUMMARY: DATES: Effective January 5, 1987. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-25-05 SIKORSKY AIRCRAFT: Amendment 39-5471. Applies to Model S-58A, B, C, D, E, F, G, H, J, BT, DT, ET, FT, HT, and JT, CH-34 series, HH-34 series, SH-34 series, UH- 34 series, and VH-34 series helicopters certificated in any category and fitted with tail rotor intermediate gearbox input bevel pinions Part Number (P/N) S1635-64114-0 and output bevel gears P/N S1635-64115-0. (See Note 1 for exempt pinion and gear configurations.) Compliance is required as indicated, unless already accomplished. (a) To preclude failure of pinions or gears identified above, accomplish the following: (1) For applicable pinions or gears that have attained 750 or less hours' time in service on the effective date of this AD, replace with a serviceable pinion or gear as required, prior to their accumulation of 1,000 hours' time in service. (2) For pinions or gears that have attained more than 750 hours' time in service on the effective date of this AD, replace with a serviceable pinion or gear as required, within the next 250 hours' time in service. (3) Operators who have not kept records of hours' time in service on individual intermediate gearbox bevel gears and bevel pinions shall substitute rotorcraft hours' time in service in lieu thereof. NOTE 1. This AD is not applicable to helicopters fitted with tail rotor intermediate gears which utilize the following pinion and gear combinations: (a) P/N 1635-64114-101 pinion and P/N S1635-64115-101 gear. (b) P/N 1635-64114-102 pinion and P/N S1635-64115-102 gear. (c) P/N 1635-64114-0 pinion and P/N S1635-64115-0 gear reworked in accordance with Sikorsky Service Bulletin 58B35-26. This rework includes remarking P/N S1635-64114-0 pinion and P/N S1635-64115-0 gear with TS-200-1 and TS-200-2, respectively. NOTE 2. Refer to the Equalized Inspection and Maintenance Program Manual SA 4047-20, Revision 10, dated December 14, 1984, or later FAA-approved revision for retirement times assigned to new or modified bevel pinions and bevel gears for the Model S-58BT, DT, ET, FT, HT, and JT helicopters, and to the Maintenance Manual SA 4045-15 Section IV, revised December 14, 1984, or later FAA-approved revision for retirement times assigned to new or modified bevel pinions and gears for the Model S-58A, B, C, D, E, F, G, H, and J helicopters. Upon request, an alternate method of compliance which provides an equivalent level of safety may be approved by the Manager, Boston Aircraft Certification Office, ANE-150, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803. Upon submission of substantiating data by an owner or operator through an FAA maintenance inspector, the Manager, Boston Aircraft Certification Office, ANE-150, FAA, 12 New England Executive Park, Burlington, Massachusetts 01803 may adjust the compliance time specified in this AD. This amendment becomes effective on January 5, 1987. FOOTER:
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