AD 54-13-01
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
The AN 73A bolts clamping the S510170 and S510156 retainers to the rotating star S10-10-4302 may fail due to insufficient torque or material weakness, leading to retainer detachment and potential catastrophic failure of the star assembly.
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Required Actions
Replace the 12 AN 73A bolts on the bottom retainer and 8 AN 73A bolts on the top retainer with torque between 25-35 inch-pounds every 60 flight hours until AN 74A bolts are installed. At next major overhaul, replace all 20 AN 73A bolts with 1/4-inch AN 74A bolts and reposition them in existing holes. Also replace 12 AN 509-10R-35 screws securing the liner and bearings with 35-40 inch-pounds torque during the same overhaul.
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Compliance Time
Compliance required as indicated. Replacements every 60 flight hours until AN 74A bolts are incorporated at the next major overhaul period of the star assembly S10-10-4300.
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Affected Aircraft
Sikorsky Model S-55 Helicopters: HRS-1/CH-19, HRS-3/H-19B, S-55, S-55B, S-55C, all serial numbers.
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Federal Register Abstract
Star Assembly Bolt Replacement
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_54-13-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 54-13-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Star Assembly Bolt Replacement 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: 54-13-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 54-13-01 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 54-13-01 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. 1. The twelve (12) AN 73A bolts which clamp the S510170 retainer to the bottom of S10-10-4302 rotating star, and the eight (8) AN 73A bolts which clamp the S510156 retainer to the top of the S10-10-4302 rotating star should be replaced. The 20 new bolts should be torqued to 25-35 inch-pounds. These replacements are to be accomplished every 60 hours until the AN 74A bolts called for in item 2. are incorporated. 2. At the next major overhaul period of the star assembly S10-10-4300, replace the twenty (20) AN 73A bolts covered in 1 with 1/4-inch diameter AN 74A bolts. The AN 74A bolts should be relocated between the existing holes. When the AN 74A bolts have been incorporated, the replacements of 1 are no longer required. 3. At the next major overhaul period of the star assembly S10-10-4300, replace the twelve (12) AN 509-10R-35 screws which secure the clamp the S12-10-4015 liner and the Y96PW1-DB bearings to the S12-10-4013 stationary star. The screws should be torqued to 35- 40 inch-pounds. (Sikorsky Service Information Circular No. 1410-222 dated March 4, 1952, through Revision D dated April 15, 1954, covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_54-13-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 54-13-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-55 Helicopters Subject: Star Assembly Bolt Replacement 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: 54-13-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 54-13-01 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-55 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 54-13-01 SIKORSKY: Applies to All Model S-55 Helicopters. Compliance required as indicated. 1. The twelve (12) AN 73A bolts which clamp the S510170 retainer to the bottom of S10-10-4302 rotating star, and the eight (8) AN 73A bolts which clamp the S510156 retainer to the top of the S10-10-4302 rotating star should be replaced. The 20 new bolts should be torqued to 25-35 inch-pounds. These replacements are to be accomplished every 60 hours until the AN 74A bolts called for in item 2. are incorporated. 2. At the next major overhaul period of the star assembly S10-10-4300, replace the twenty (20) AN 73A bolts covered in 1 with 1/4-inch diameter AN 74A bolts. The AN 74A bolts should be relocated between the existing holes. When the AN 74A bolts have been incorporated, the replacements of 1 are no longer required. 3. At the next major overhaul period of the star assembly S10-10-4300, replace the twelve (12) AN 509-10R-35 screws which secure the clamp the S12-10-4015 liner and the Y96PW1-DB bearings to the S12-10-4013 stationary star. The screws should be torqued to 35- 40 inch-pounds. (Sikorsky Service Information Circular No. 1410-222 dated March 4, 1952, through Revision D dated April 15, 1954, covers this same subject.) FOOTER:
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