AD 68-21-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sikorsky Aircraft Corporation | S-61A | Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61L | Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters |
| aircraft | Sikorsky Aircraft Corporation | S-61N | Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters |
Unsafe Condition
Failure of the automatic flight control system (AFCS) could result in loss of control of the helicopter.
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Required Actions
Deactivate the AFCS by disconnecting power sources to the AFCS system and channel monitor panel, pull circuit breakers, safety the buttons, disconnect electrical connectors at aux. servos, secure to wire bundles, and ground all pins on each plug. Reactivation requires incorporation of approved alterations or service bulletins.
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Compliance Time
within the next ten hours time in service after the effective date of this Airworthiness Directive unless already accomplished
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Affected Aircraft
Sikorsky Models S-61A, S-61L, and S-61N Helicopters
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Federal Register Abstract
Deactivate AFCS
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_68-21-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-21-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters Subject: Deactivate AFCS Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/24/1968 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61L | S-61N Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 68-21-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-671 AD NUMBER: 68-21-06 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters ACTION: SUMMARY: DATES: Effective October 24, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-21-06 SIKORSKY: Amendment 39-671. Applies to S-61A, S-61L, S-61N Type Helicopters. (a) Within the next ten hours time in service after the effective date of this Airworthiness Directive unless already accomplished, deactivate the automatic flight control system (AFCS) by disconnecting the power sources to the AFCS system and the channel monitor panel as follows: (1) Pull circuit breakers for electric power to the channel monitor panel and the AFCS system and safety the circuitbreaker buttons in the tripped position. (2) Disconnect electrical connectors at the aux. servos and secure to wire bundle. Electrically ground all three pins on each plug on the aux. servos. (b) For Models S-61L and S-61N, the AFCS may be reactivated when Sikorsky Service Bulletin No. 61B55-10A, dated October 4, 1968, or later FAA approved revision, or equivalent alteration approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (c) For Model S-61A, the AFCS may be reactivated when an alteration approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region is incorporated. This amendment is effective October 24, 1968, and supersedes the telegram dated September 17, 1968 on this subject. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_68-21-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 68-21-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters Subject: Deactivate AFCS Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 10/24/1968 Make: Sikorsky Aircraft Corporation Model: S-61A | S-61L | S-61N 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: 68-21-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-671 AD NUMBER: 68-21-06 SUBJECT HEADING: Airworthiness Directives; Sikorsky Models S-61A, S-61L, and S-61N Helicopters ACTION: SUMMARY: DATES: Effective October 24, 1968. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 68-21-06 SIKORSKY: Amendment 39-671. Applies to S-61A, S-61L, S-61N Type Helicopters. (a) Within the next ten hours time in service after the effective date of this Airworthiness Directive unless already accomplished, deactivate the automatic flight control system (AFCS) by disconnecting the power sources to the AFCS system and the channel monitor panel as follows: (1) Pull circuit breakers for electric power to the channel monitor panel and the AFCS system and safety the circuitbreaker buttons in the tripped position. (2) Disconnect electrical connectors at the aux. servos and secure to wire bundle. Electrically ground all three pins on each plug on the aux. servos. (b) For Models S-61L and S-61N, the AFCS may be reactivated when Sikorsky Service Bulletin No. 61B55-10A, dated October 4, 1968, or later FAA approved revision, or equivalent alteration approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. (c) For Model S-61A, the AFCS may be reactivated when an alteration approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region is incorporated. This amendment is effective October 24, 1968, and supersedes the telegram dated September 17, 1968 on this subject. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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