AD 84-01-51

final rule

Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft

AD Number
84-01-51
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Sikorsky Aircraft Corporation S-61A Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61D Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61E Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61L Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61N Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61NM Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61R Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
aircraft Sikorsky Aircraft Corporation S-61V Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft

Unsafe Condition

Crack in rotary wing head shaft nut with improper Rockwell hardness due to possible incomplete processing of nuts, part number S6110-21082-0.

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

Required Actions

Fluorescent magnetic particle inspect and Rockwell hardness test the nut per Sikorsky Service Bulletin 61B10-14 and message CST-P-83-171. Replace cracked or out-of-hardness nuts before further flight with compliant nuts. Bake and mark acceptable nuts at 375°F±25°F for 3 hours.

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

Compliance Time

within the next 25 hours time in service after the effective date of this AD

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

Affected Aircraft

Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, S-61L, S-61N, S-61NM, S-61R, S-61V aircraft certificated in all categories.

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

Federal Register Abstract

Rotary Wing Head Shaft Nut

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_84-01-51.html
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AD Number:
84-01-51
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
Subject:
Rotary Wing Head Shaft Nut
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
03/27/1984
Make:
Sikorsky Aircraft Corporation
Model:
S-61A | S-61D | S-61E | S-61L | S-61N | S-61NM | S-61R | S-61V
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: 84-01-51
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4826

AD NUMBER:   84-01-51

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective March 27, 1984.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-01-51 SIKORSKY AIRCRAFT: Amendment 39-4826. Applies to Model S-61 series aircraft certificated in all categories.

Compliance required within the next 25 hours time in service after the effective date of this AD, unless already accomplished.

As a result of finding a crack in a rotary wing head shaft nut and finding the nut had improper Rockwell hardness and because of possible incomplete processing of these nuts, P/N S6110-21082-0, accomplish the following:

(a) Fluorescent magnetic particle inspect and Rockwell hardness test the rotary wing head shaft nut, in accordance with Section B of Sikorsky Service Bulletin No. 61B10-14, dated November 3, 1969, as revised by Sikorsky Message Number CST-P-83-171, Revision 2, dated December 5, 1983. Visible magnetic particle inspection and Rockwell hardness test in accordance with Section B of the service bulletin may be used as an alternate to fluorescent magnetic particle inspection and Rockwell hardness test.

(b) Any nut with cracks or not within the proper hardness range specified in Sikorsky service documents specified in paragraph (a) of this AD must be replaced before further flight with a nut that has been inspected in accordance with paragraph (a) of this AD and baked and marked in accordance with paragraph (c) of this AD or with a Sikorsky provided nut inspected and marked in accordance with this AD.

(c) Any nut not cracked and with proper hardness as specified in the Sikorsky service documents must be baked at 375 degrees fahrenheit plus/minus 25 degrees fahrenheit for a minimum of three hours and marked in accordance with the Sikorsky service documents specified in paragraph (a) of this AD.

(d) Alternate inspections, processes, or other means of compliance which provide an equivalent level of safety to this AD must be approved by the Manager, Boston Aircraft Certification Branch, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. In accordance with FAR 21.197, flight is permitted to a base where the requirements of this AD -may be accomplished.

Sikorsky Service Bulletin No. 61B10-14, dated November 3, 1969, and Sikorsky message Number CST-P-83-171, Revision 2, dated December 5, 1983, identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 551(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to United Technologies Corporation, Sikorsky Aircraft, North Main Street, Stratford, Connecticut 06602, ATTN: S-61 Commercial Product Support Department. These documents also may be examined in the Office of the Regional Counsel, Federal Aviation Administration, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment supersedes Amendment 39-889 (34 FR 19545), AD 69-25-05, which became effective December 10, 1969.

This amendment becomes effective March 27, 1984, as to all persons except those persons to whom it was made immediately effective by the telegram dated December 30, 1983, which contained this amendment.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_84-01-51.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
84-01-51
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft
Subject:
Rotary Wing Head Shaft Nut
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
03/27/1984
Make:
Sikorsky Aircraft Corporation
Model:
S-61A | S-61D | S-61E | S-61L | S-61N | S-61NM | S-61R | S-61V
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: 84-01-51
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-4826

AD NUMBER:   84-01-51

SUBJECT HEADING:   Airworthiness Directives; SIKORSKY AIRCRAFT Model S-61 Series Aircraft

ACTION:  

SUMMARY:  

DATES:   Effective March 27, 1984.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
84-01-51 SIKORSKY AIRCRAFT: Amendment 39-4826. Applies to Model S-61 series aircraft certificated in all categories.

Compliance required within the next 25 hours time in service after the effective date of this AD, unless already accomplished.

As a result of finding a crack in a rotary wing head shaft nut and finding the nut had improper Rockwell hardness and because of possible incomplete processing of these nuts, P/N S6110-21082-0, accomplish the following:

(a) Fluorescent magnetic particle inspect and Rockwell hardness test the rotary wing head shaft nut, in accordance with Section B of Sikorsky Service Bulletin No. 61B10-14, dated November 3, 1969, as revised by Sikorsky Message Number CST-P-83-171, Revision 2, dated December 5, 1983. Visible magnetic particle inspection and Rockwell hardness test in accordance with Section B of the service bulletin may be used as an alternate to fluorescent magnetic particle inspection and Rockwell hardness test.

(b) Any nut with cracks or not within the proper hardness range specified in Sikorsky service documents specified in paragraph (a) of this AD must be replaced before further flight with a nut that has been inspected in accordance with paragraph (a) of this AD and baked and marked in accordance with paragraph (c) of this AD or with a Sikorsky provided nut inspected and marked in accordance with this AD.

(c) Any nut not cracked and with proper hardness as specified in the Sikorsky service documents must be baked at 375 degrees fahrenheit plus/minus 25 degrees fahrenheit for a minimum of three hours and marked in accordance with the Sikorsky service documents specified in paragraph (a) of this AD.

(d) Alternate inspections, processes, or other means of compliance which provide an equivalent level of safety to this AD must be approved by the Manager, Boston Aircraft Certification Branch, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803. In accordance with FAR 21.197, flight is permitted to a base where the requirements of this AD -may be accomplished.

Sikorsky Service Bulletin No. 61B10-14, dated November 3, 1969, and Sikorsky message Number CST-P-83-171, Revision 2, dated December 5, 1983, identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 551(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to United Technologies Corporation, Sikorsky Aircraft, North Main Street, Stratford, Connecticut 06602, ATTN: S-61 Commercial Product Support Department. These documents also may be examined in the Office of the Regional Counsel, Federal Aviation Administration, Southwest Region, 4400 Blue Mound Road, Fort Worth, Texas 76106.

This amendment supersedes Amendment 39-889 (34 FR 19545), AD 69-25-05, which became effective December 10, 1969.

This amendment becomes effective March 27, 1984, as to all persons except those persons to whom it was made immediately effective by the telegram dated December 30, 1983, which contained this amendment.

FOOTER:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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