AD 56-23-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation | HRS-1/CH-19 | Airworthiness Directives; Sikorsky Model S-55 Helicopters |
| aircraft | Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation | HRS-3/H-19B | Airworthiness Directives; Sikorsky Model S-55 Helicopters |
| aircraft | Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation | S-55 | Airworthiness Directives; Sikorsky Model S-55 Helicopters |
| aircraft | Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation | S-55B | Airworthiness Directives; Sikorsky Model S-55 Helicopters |
| aircraft | Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation | S-55C | Airworthiness Directives; Sikorsky Model S-55 Helicopters |
Unsafe Condition
Horizontal hinge pin assembly, part numbers S10-10-3331 and S10-10-3331-1, may fail due to fatigue after accumulating 750 hours service.
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Required Actions
Replace horizontal hinge pin assemblies with part numbers S10-10-3331 and S10-10-3331-1 that have 750 hours service by December 1, 1956, or earlier if the 850-hour limit is reached. Parts with 850 hours or more must be replaced before further service. Thereafter, retire these parts at not more than 750 hours service.
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Compliance Time
by December 1, 1956, or prior to the accumulation of 850 hours, whichever occurs first
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Affected Aircraft
Sikorsky Model S-55 Helicopters: all serial numbers with horizontal hinge pin assembly part numbers S10-10-3331 and S10-10-3331-1
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Federal Register Abstract
Horizontal Hinge Pin Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_56-23-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 56-23-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Horizontal Hinge Pin Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation Model: HRS-1/CH-19 | HRS-3/H-19B | S-55 | S-55B | S-55C Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 56-23-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 56-23-03 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 56-23-03 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. Due to additional failures, it has been found necessary to lower the retirement time specified in AD 56-10-02. Accordingly, the horizontal hinge pin assembly, P/N S10-10-3331 and S10-10-3331-1 with 750 hours service must be replaced by December 1, 1956, or prior to the accumulation of 850 hours, whichever occurs first. Parts with 850 hours or more must be replaced prior to further service. Thereafter, P/N S10-10-3331 and S10-10-3331-1 are to be retired at not more than 750 hours. This supersedes AD 56-10-02. FOOTER:
Document Text
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AD Final Rules - DRS_56-23-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 56-23-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Horizontal Hinge Pin Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Orlando Helicopter Airways, Inc. | Sikorsky Aircraft Corporation Model: HRS-1/CH-19 | HRS-3/H-19B | S-55 | S-55B | S-55C 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: 56-23-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 56-23-03 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 56-23-03 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. Due to additional failures, it has been found necessary to lower the retirement time specified in AD 56-10-02. Accordingly, the horizontal hinge pin assembly, P/N S10-10-3331 and S10-10-3331-1 with 750 hours service must be replaced by December 1, 1956, or prior to the accumulation of 850 hours, whichever occurs first. Parts with 850 hours or more must be replaced prior to further service. Thereafter, P/N S10-10-3331 and S10-10-3331-1 are to be retired at not more than 750 hours. This supersedes AD 56-10-02. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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