AD 84-17-01

final rule

Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters

AD Number
84-17-01
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 Sikorsky Aircraft Corporation S-76A Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters

Unsafe Condition

Failure of the main rotor pitch horn, part number 76102-08011-042, due to fatigue or wear.

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

Required Actions

Remove and replace the main rotor pitch horn with a new or airworthy part of the same part number, ensuring it has less than 5,500 hours time in service. Use the Sikorsky S-76A Maintenance Manual or FAA-approved equivalent. Special flight permits may be issued under FAR Sections 21.197 and 21.199.

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

Compliance Time

Prior to further flight if the pitch horn has more than 5,500 hours time in service on the effective date (January 10, 1985), or before accumulating 5,500 hours time in service if it has 5,500 hours or less. Thereafter, comply every 5,500 hours time in service.

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

Affected Aircraft

Sikorsky Aircraft Corporation Model S-76A helicopters with main rotor pitch horn part number 76102-08011-042 installed.

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

Federal Register Abstract

Main Rotor Pitch Horn

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_84-17-01.html
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Details
AD Number:
84-17-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters
Subject:
Main Rotor Pitch Horn
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/10/1985
Make:
Sikorsky Aircraft Corporation
Model:
S-76A
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Superseded AD: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Superseded By: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: 84-17-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4972

AD NUMBER:   84-17-01

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective January 10, 1985.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-17-01 SIKORSKY AIRCRAFT: Amendment 39-4972. Applies to Model S-76A helicopters with main rotor pitch horn, P/N 76102-08011-042, installed and certificated in all categories.

Compliance is required as indicated, unless already accomplished.

For helicopters with main rotor pitch horns with more than 5,500 hours time in service on the effective date of this AD, compliance is required prior to further flight, unless already accomplished, and thereafter at intervals not to exceed 5,500 hours time in service.

For helicopters with main rotor pitch horns with 5,500 hours or less time in service on the effective date of this AD, compliance is required prior to the accumulation of 5,500 hours time in service, unless already accomplished, and thereafter at intervals not to exceed 5,500 hours time in service.

To prevent possible failure of the main rotor pitch horn, accomplish the following:

(a) Remove and replace the main rotor pitch horn, P/N 76102-08011-042, with a new or an airworthy part of the same part number, that has less than 5,500 hours time in service in accordance with Sikorsky S-76A Maintenance Manual SA4047-76-2, Section 65-12-03, dated March 1, 1984, or FAA approved equivalent.

(b) Special flight permit may be issued in accordance with FAR Sections 21.197 and 21.199 to operate a helicopter to a base for replacement of the main rotor pitch horns required by this AD.

(c) Alternate repairs, modifications, or other means of compliance to the AD which provide an equivalent level of safety may be approved by the Manager, Boston Aircraft Certification Office, FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803.

This amendment becomes effective January 10, 1985, as to all persons except those persons to whom it was made immediately effective by priority letter AD 84-17-01, issued August 16, 1984, which contained this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_84-17-01.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
84-17-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters
Subject:
Main Rotor Pitch Horn
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/10/1985
Make:
Sikorsky Aircraft Corporation
Model:
S-76A
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: 84-17-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4972

AD NUMBER:   84-17-01

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-76A Helicopters

ACTION:  

SUMMARY:  

DATES:   Effective January 10, 1985.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-17-01 SIKORSKY AIRCRAFT: Amendment 39-4972. Applies to Model S-76A helicopters with main rotor pitch horn, P/N 76102-08011-042, installed and certificated in all categories.

Compliance is required as indicated, unless already accomplished.

For helicopters with main rotor pitch horns with more than 5,500 hours time in service on the effective date of this AD, compliance is required prior to further flight, unless already accomplished, and thereafter at intervals not to exceed 5,500 hours time in service.

For helicopters with main rotor pitch horns with 5,500 hours or less time in service on the effective date of this AD, compliance is required prior to the accumulation of 5,500 hours time in service, unless already accomplished, and thereafter at intervals not to exceed 5,500 hours time in service.

To prevent possible failure of the main rotor pitch horn, accomplish the following:

(a) Remove and replace the main rotor pitch horn, P/N 76102-08011-042, with a new or an airworthy part of the same part number, that has less than 5,500 hours time in service in accordance with Sikorsky S-76A Maintenance Manual SA4047-76-2, Section 65-12-03, dated March 1, 1984, or FAA approved equivalent.

(b) Special flight permit may be issued in accordance with FAR Sections 21.197 and 21.199 to operate a helicopter to a base for replacement of the main rotor pitch horns required by this AD.

(c) Alternate repairs, modifications, or other means of compliance to the AD which provide an equivalent level of safety may be approved by the Manager, Boston Aircraft Certification Office, FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803.

This amendment becomes effective January 10, 1985, as to all persons except those persons to whom it was made immediately effective by priority letter AD 84-17-01, issued August 16, 1984, which contained this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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