AD 77-06-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Enstrom Helicopter Corporation, The | 280C | Airworthiness Directives; Enstrom Model F28C and 280C Helicopters |
| aircraft | Enstrom Helicopter Corporation, The | F-28C | Airworthiness Directives; Enstrom Model F28C and 280C Helicopters |
Unsafe Condition
Tail rotor assembly P/N 28-150000-3 with blade grip fittings P/N 28-150013-11 could fail, leading to loss of tail rotor control.
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Required Actions
Remove the tail rotor assembly P/N 28-150000-3 and replace it with an airworthy assembly using forged blade grip fittings P/N 28-150013-11. Return the removed assembly to Enstrom Helicopter Corporation.
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Compliance Time
Before further flight
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Affected Aircraft
Enstrom Model F28C (serial numbers 364, 367, 373, 374) and Model 280C (serial numbers 1007, 1020, 1060, 1062, 1065)
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Federal Register Abstract
Tail Rotor Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_77-06-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-06-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Enstrom Model F28C and 280C Helicopters Subject: Tail Rotor Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/31/1977 Make: Enstrom Helicopter Corporation, The Model: 280C | F-28C Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 77-06-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2855 AD NUMBER: 77-06-04 SUBJECT HEADING: Airworthiness Directives; Enstrom Model F28C and 280C Helicopters ACTION: SUMMARY: DATES: Effective March 31, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-06-04 ENSTROM: Amendment 39-2855. Applies to Enstrom Model F28C helicopters with serial numbers 364, 367, 373 and 374 and Model 280C with serial numbers 1007, 1020, 1060, 1062, 1065 certificated in all categories. Before further flight, unless already accomplished, remove from service the tail rotor assembly P/N 28-150000-3 and replace with an airworthy assembly which has been assembled using forged blade grip fittings P/N 28-150013-11. The removed tail rotor assembly should be returned to Enstrom Helicopter Corporation, Menominee, Michigan 49858. This amendment becomes effective March 31, 1977, to all persons except those to whom it was made effective earlier by air mail letter dated March 2, 1977. FOOTER:
Document Text
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AD Final Rules - DRS_77-06-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 77-06-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Enstrom Model F28C and 280C Helicopters Subject: Tail Rotor Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/31/1977 Make: Enstrom Helicopter Corporation, The Model: 280C | F-28C 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: 77-06-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2855 AD NUMBER: 77-06-04 SUBJECT HEADING: Airworthiness Directives; Enstrom Model F28C and 280C Helicopters ACTION: SUMMARY: DATES: Effective March 31, 1977. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 77-06-04 ENSTROM: Amendment 39-2855. Applies to Enstrom Model F28C helicopters with serial numbers 364, 367, 373 and 374 and Model 280C with serial numbers 1007, 1020, 1060, 1062, 1065 certificated in all categories. Before further flight, unless already accomplished, remove from service the tail rotor assembly P/N 28-150000-3 and replace with an airworthy assembly which has been assembled using forged blade grip fittings P/N 28-150013-11. The removed tail rotor assembly should be returned to Enstrom Helicopter Corporation, Menominee, Michigan 49858. This amendment becomes effective March 31, 1977, to all persons except those to whom it was made effective earlier by air mail letter dated March 2, 1977. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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