AD 55-25-04
final rule
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
Failure of the tail cone skin in the area where the tail cone is spliced to the fuselage
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the tail cone skin for cracks and add reinforcements based on tail cone hours: for <1,500 hours, reinforce at next major inspection or within 150 hours; for 1,500-2,000 hours, inspect for cracks, reinforce if no cracks, replace and reinforce if cracks found; for ≥2,000 hours, inspect within 50 hours, reinforce or replace as needed following Sikorsky IC 1420-632.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Compliance required as indicated (specific timelines vary by tail cone hours: next major inspection or within 150 hours for <1,500 hours; next major inspection or within 150 hours for 1,500-2,000 hours; next intermediate inspection or within 50 hours for ≥2,000 hours)
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Sikorsky Model S-55 Helicopters (all serial numbers)
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Tail Cone Skin Reinforcements
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_55-25-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-25-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Tail Cone Skin Reinforcements 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: 55-25-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-25-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-25-04 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. A recent failure of the tail cone skin in the area where the tail cone is spliced to the fuselage has been reported in a Model S-55 helicopter. Since this is the means of attaching the tail cone to the fuselage and to preclude further failures, the following inspections and reinforcements for the splice area are considered necessary. 1. Tail cones with less than 1,500 hours, add reinforcements at the next major inspection or within the next 150 hours. 2. Tail cones with 1,500 hours to 2,000 hours, inspect the skin for cracks at the next major inspection or within the next 150 hours. If no cracks are found, add reinforcements. If cracks are found, replace the skin and add reinforcements. 3. Tail cones with 2,000 hours or more, inspect the skin for cracks at the next intermediate inspection or within the next 50 hours. If no cracks are found, add reinforcements. If cracks are found, replace the skin and add reinforcements. 4. The inspection procedures to be followed, the reinforcements to be added and the method of attaching the reinforcements are explained in detail in Sikorsky Information Circular No. 1420-632. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_55-25-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 55-25-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Tail Cone Skin Reinforcements 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: 55-25-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 55-25-04 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 55-25-04 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. A recent failure of the tail cone skin in the area where the tail cone is spliced to the fuselage has been reported in a Model S-55 helicopter. Since this is the means of attaching the tail cone to the fuselage and to preclude further failures, the following inspections and reinforcements for the splice area are considered necessary. 1. Tail cones with less than 1,500 hours, add reinforcements at the next major inspection or within the next 150 hours. 2. Tail cones with 1,500 hours to 2,000 hours, inspect the skin for cracks at the next major inspection or within the next 150 hours. If no cracks are found, add reinforcements. If cracks are found, replace the skin and add reinforcements. 3. Tail cones with 2,000 hours or more, inspect the skin for cracks at the next intermediate inspection or within the next 50 hours. If no cracks are found, add reinforcements. If cracks are found, replace the skin and add reinforcements. 4. The inspection procedures to be followed, the reinforcements to be added and the method of attaching the reinforcements are explained in detail in Sikorsky Information Circular No. 1420-632. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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