AD 85-25-03

final rule

Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters

AD Number
85-25-03
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Erickson Air-Crane S-64E Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters

Unsafe Condition

Cracked or corroded main rotor head torque tube inner bracket assembly, Part Number S1510-21332-0, could result in failure of the main rotor head assembly.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Visually inspect the torque tube inner bracket assembly with a 10-power or higher magnifying glass for cracks and corrosion as per Sikorsky ASB 64B10-4A. Replace if cracked or corroded beyond limits; rework if corrosion is within limits. Ferry operations allowed under FAR 21.197/199.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Prior to the first flight of each day after the effective date (December 30, 1985). For cracked parts: replace prior to further flight. For corrosion: determine extent prior to further flight and replace or rework as needed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Erickson Air-Crane Model S-64E helicopters, all serial numbers, certified in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Torque Tube Inner Bracket Assembly

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_85-25-03.html
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AD Number:
85-25-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters
Subject:
Torque Tube Inner Bracket Assembly
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/30/1985
Make:
Erickson Air-Crane
Model:
S-64E
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Superseded AD: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Superseded By: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: 85-25-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5172

AD NUMBER:   85-25-03

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective December 30, 1985.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-25-03 SIKORSKY AIRCRAFT: Amendment 39-5172. Applies to Model S-64E helicopters, certificated in any category.

Compliance is required as indicated, unless already accomplished.

To prevent operation with a cracked main rotor head torque tube inner bracket, accomplish the following:

(a) Prior to the first flight of each day, after the effective date of this AD, visually inspect with a 10-power or higher magnifying glass the main rotor head torque tube inner bracket assembly, Part Number S1510-21332-0, for cracks and/or corrosion in accordance with Section 2, Paragraph A, of Sikorsky Alert Service Bulletin (ASB) No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(b) If the torque tube inner bracket assembly is cracked, replace with a serviceable torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(c) If the torque tube inner bracket assembly is corroded, determine the extent and limits of the corrosion prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB-No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent. If the extent or limits of the corrosion are exceeded, replace with a serviceable torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent. Otherwise, rework the torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph B, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(d) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished.

(e) Upon request, an alternative means of compliance with the requirements of this AD which provide an equivalent level of safety may be used when approved by the Manager, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7112.

Sikorsky ASB No. 64B10-4A, dated July 17, 1985, identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Sikorsky Aircraft Division, United Technologies Corporation, North Main Street, Stratford, Connecticut 06601. These documents may also be examined at the Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective December 30, 1985.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_85-25-03.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
85-25-03
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters
Subject:
Torque Tube Inner Bracket Assembly
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/30/1985
Make:
Erickson Air-Crane
Model:
S-64E
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: 85-25-03
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-5172

AD NUMBER:   85-25-03

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-64E Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective December 30, 1985.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
85-25-03 SIKORSKY AIRCRAFT: Amendment 39-5172. Applies to Model S-64E helicopters, certificated in any category.

Compliance is required as indicated, unless already accomplished.

To prevent operation with a cracked main rotor head torque tube inner bracket, accomplish the following:

(a) Prior to the first flight of each day, after the effective date of this AD, visually inspect with a 10-power or higher magnifying glass the main rotor head torque tube inner bracket assembly, Part Number S1510-21332-0, for cracks and/or corrosion in accordance with Section 2, Paragraph A, of Sikorsky Alert Service Bulletin (ASB) No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(b) If the torque tube inner bracket assembly is cracked, replace with a serviceable torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(c) If the torque tube inner bracket assembly is corroded, determine the extent and limits of the corrosion prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB-No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent. If the extent or limits of the corrosion are exceeded, replace with a serviceable torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph A, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent. Otherwise, rework the torque tube inner bracket assembly prior to further flight in accordance with Section 2, Paragraph B, of Sikorsky ASB No. 64B10-4A, dated July 17, 1985, or an FAA-approved equivalent.

(d) Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished.

(e) Upon request, an alternative means of compliance with the requirements of this AD which provide an equivalent level of safety may be used when approved by the Manager, Boston Aircraft Certification Office, 12 New England Executive Park, Burlington, Massachusetts 01803, telephone (617) 273-7112.

Sikorsky ASB No. 64B10-4A, dated July 17, 1985, identified and described in this directive is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Sikorsky Aircraft Division, United Technologies Corporation, North Main Street, Stratford, Connecticut 06601. These documents may also be examined at the Office of the Regional Counsel, FAA, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment becomes effective December 30, 1985.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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