AD 67-29-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-51 | Airworthiness Directives; Sikorsky Model S-51 Helicopters |
Unsafe Condition
Failure of sleeve and tube assembly P/N S535180 could lead to loss of tail rotor power.
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Required Actions
Perform torsional checks every 50 aircraft hours' time in service, including applying rotor brake, inducing torsional force on tail rotor drive shafting, and inspecting shaft ends for movement. Daily inspect for loose rivets indicated by black fretting residue or movement, and cracks at tube and sleeve joints. Replace assembly if movement or cracks are found; loose rivets may be replaced with specified rivets after drilling holes to specified diameters.
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Compliance Time
Immediately upon the effective date of this AD and every 50 aircraft hours' time in service thereafter
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Affected Aircraft
Sikorsky Model S-51 Helicopters, all serial numbers
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Federal Register Abstract
Tail Rotor Sleeve & Tube Assy
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_67-29-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 67-29-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-51 Helicopters Subject: Tail Rotor Sleeve & Tube Assy Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/31/1967 Make: Sikorsky Aircraft Corporation Model: S-51 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 67-29-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-502 AD NUMBER: 67-29-06 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-51 Helicopters ACTION: SUMMARY: DATES: Effective October 31, 1967. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 67-29-06 SIKORSKY: Amdt. 39-502 Part 39 Federal Register November 2, 1967. Applies to all S-51 type Helicopters. Compliance required as indicated unless already accomplished. To preclude the possibility of loss of tail rotor power due to failure of sleeve and tube assembly, P/N S535180, accomplish the following: (a) Immediately upon the effective date of this AD and every 50 aircraft hours' time in service thereafter, perform the following torsional check on sleeve and tube assembly P/N S535180 as follows: 1. Apply rotor brake. 2. Induce a torsional force in both clockwise and counter-clockwise directions to tail rotor drive shafting by hand applied light rotational pressure on tail rotor blades. 3. Inspect shaft ends for evidence of movement between end fittings, rivets and tube. 4. If evidence of movement is observed, replace sleeve and tube assembly P/N S535180 with like new or serviceable part. (b) Following the effective date of this AD daily inspect sleeve and tube assembly P/N S535180 for loose rivets as evidenced by the presence of black fretting residue around rivet heads, or actual movement of the rivets, and the presence of cracks in the areas where the tube and sleeves (adapters) are joined. If cracks are found replace sleeve and tube assembly P/N S535180 with like new or serviceable part. Loose rivets may be replaced by removing the existing rivets, drilling No. 2 (.221) diameter and installing new rivets P/N MS20470-B7-9. Alternate oversize rivets P/N MS20470-B8-10 may be used if holes are drilled to No. F. (.257) diameter. (c) Upon request, with substantiating data submitted through an FAA maintenance inspector, compliance times may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (Sikorsky Aircraft telegram to all operators dated September 5, 1967 covers this same subject.) This amendment effective October 31, 1967. FOOTER:
Document Text
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AD Final Rules - DRS_67-29-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 67-29-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Model S-51 Helicopters Subject: Tail Rotor Sleeve & Tube Assy Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/31/1967 Make: Sikorsky Aircraft Corporation Model: S-51 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: 67-29-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-502 AD NUMBER: 67-29-06 SUBJECT HEADING: Airworthiness Directives; Sikorsky Model S-51 Helicopters ACTION: SUMMARY: DATES: Effective October 31, 1967. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 67-29-06 SIKORSKY: Amdt. 39-502 Part 39 Federal Register November 2, 1967. Applies to all S-51 type Helicopters. Compliance required as indicated unless already accomplished. To preclude the possibility of loss of tail rotor power due to failure of sleeve and tube assembly, P/N S535180, accomplish the following: (a) Immediately upon the effective date of this AD and every 50 aircraft hours' time in service thereafter, perform the following torsional check on sleeve and tube assembly P/N S535180 as follows: 1. Apply rotor brake. 2. Induce a torsional force in both clockwise and counter-clockwise directions to tail rotor drive shafting by hand applied light rotational pressure on tail rotor blades. 3. Inspect shaft ends for evidence of movement between end fittings, rivets and tube. 4. If evidence of movement is observed, replace sleeve and tube assembly P/N S535180 with like new or serviceable part. (b) Following the effective date of this AD daily inspect sleeve and tube assembly P/N S535180 for loose rivets as evidenced by the presence of black fretting residue around rivet heads, or actual movement of the rivets, and the presence of cracks in the areas where the tube and sleeves (adapters) are joined. If cracks are found replace sleeve and tube assembly P/N S535180 with like new or serviceable part. Loose rivets may be replaced by removing the existing rivets, drilling No. 2 (.221) diameter and installing new rivets P/N MS20470-B7-9. Alternate oversize rivets P/N MS20470-B8-10 may be used if holes are drilled to No. F. (.257) diameter. (c) Upon request, with substantiating data submitted through an FAA maintenance inspector, compliance times may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (Sikorsky Aircraft telegram to all operators dated September 5, 1967 covers this same subject.) This amendment effective October 31, 1967. FOOTER:
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