AD 86-12-06
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron, Inc. | 214ST | Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 214ST Helicopters |
Unsafe Condition
Failure of the main rotor yoke assembly due to fatigue cracking.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Remove and replace the main rotor yoke assembly not later than 2,500 hours time in service. For yoke assemblies with over 2,450 hours as of July 1, 1986, replace within next 50 hours time in service or by July 1, 1986, whichever comes first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Not later than 2,500 hours time in service. For those with over 2,450 hours as of July 1, 1986, within next 50 hours time in service or by July 1, 1986, whichever comes first.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bell Helicopter Textron, Inc. Model 214ST helicopters, serial numbers 18401, 18402, 18403, and 28101 through 28159, equipped with main rotor yoke assembly P/N 214-010-105-001.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Yoke Assemblies
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-12-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-12-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 214ST Helicopters Subject: Main Rotor Yoke Assemblies Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/01/1986 Make: Bell Helicopter Textron, Inc. Model: 214ST Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 86-12-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5329 AD NUMBER: 86-12-06 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 214ST Helicopters ACTION: SUMMARY: DATES: Effective July 1, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-12-06 BELL HELICOPTER TEXTRON, INC.: Amendment 39-5329. Applies to Bell Helicopter Textron, Inc., Model 214ST helicopters, S/N's 18401, 18402, 18403, and 28101 through 28159, certificated in any category, equipped with main rotor yoke assembly P/N 214- 010-105-001. Compliance is required as indicated, unless already accomplished. (a) To prevent failure of the main rotor yoke assembly, remove and replace the yoke assembly not later than 2,500 hours time in service. For yoke assemblies that have accumulated more than 2,450 hours time in service as of the effective date of this AD, remove and replace the yoke assembly within the next 50 hours time in service or by July 1, 1986, whichever comes first. (b) Any alternate method of compliance which provides an equivalent level of safety with this AD may be used when approved by the Manager, Certification Branch, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106. This amendment becomes effective July 1, 1986. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_86-12-06.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-12-06 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 214ST Helicopters Subject: Main Rotor Yoke Assemblies Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/01/1986 Make: Bell Helicopter Textron, Inc. Model: 214ST 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: 86-12-06 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5329 AD NUMBER: 86-12-06 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 214ST Helicopters ACTION: SUMMARY: DATES: Effective July 1, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-12-06 BELL HELICOPTER TEXTRON, INC.: Amendment 39-5329. Applies to Bell Helicopter Textron, Inc., Model 214ST helicopters, S/N's 18401, 18402, 18403, and 28101 through 28159, certificated in any category, equipped with main rotor yoke assembly P/N 214- 010-105-001. Compliance is required as indicated, unless already accomplished. (a) To prevent failure of the main rotor yoke assembly, remove and replace the yoke assembly not later than 2,500 hours time in service. For yoke assemblies that have accumulated more than 2,450 hours time in service as of the effective date of this AD, remove and replace the yoke assembly within the next 50 hours time in service or by July 1, 1986, whichever comes first. (b) Any alternate method of compliance which provides an equivalent level of safety with this AD may be used when approved by the Manager, Certification Branch, Federal Aviation Administration, 4400 Blue Mound Road, Fort Worth, Texas 76106. This amendment becomes effective July 1, 1986. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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