AD 93-21-10
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron, Inc. | 214B | Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters |
| aircraft | Bell Helicopter Textron, Inc. | 214B-1 | Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters |
Unsafe Condition
Failure of the main rotor yoke assembly, leading to loss of the main rotor and subsequent loss of control of the helicopter.
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Required Actions
Replace the main rotor yoke assembly based on time-in-service thresholds, install new airspeed versus altitude decals within 50 hours' time-in-service, and inspect the yoke for straightness within 50 hours' time-in-service and every 1,200 hours thereafter.
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Compliance Time
Required as indicated, unless accomplished previously.
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Affected Aircraft
Bell Helicopter Textron, Inc. Model 214B and 214B-1 helicopters, serial numbers 28001 through 28070, equipped with main rotor yoke assembly part number 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 Assembly
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_93-21-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-21-10 Document Type: AD Final Rules Docket Number: 91-ASW-18 Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters Subject: Main Rotor Yoke Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/18/1994 Make: Bell Helicopter Textron, Inc. Model: 214B | 214B-1 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 93-21-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-ASW-18 AMENDMENT: 39-8724 AD NUMBER: 93-21-10 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters ACTION: SUMMARY: DATES: Effective January 18, 1994. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-21-10 BELL HELICOPTER TEXTRON, INC. (BHTI): Amendment 39-8724. Docket Number 91-ASW-18. Applicability: Model 214B and 214B-1 helicopters, serial numbers (S/N's) 28001 through 28070, equipped with main rotor yoke assembly (assembly), part number (P/N) 214-010-105-001, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent failure of the assembly, loss of the main rotor, and subsequent loss of control of the helicopter, accomplish the following: (a) For assemblies that have 3,700 hours' or less time-in-service on the effective date of this airworthiness directive (AD), replace the assembly on or before reaching 3,750 hours' time-in-service. For assemblies that have more than 3,700 hours' time-in-service on the effective date of this AD, replace the assembly within the next 50 hours' time-in-service. (b) Within 50 hours' time-in-service after the effective date of this AD, install new airspeed versus altitude decals, P/N 214-075-256-105 for BHTI Model 214B-1 and P/N 214-075-256-107 for Model 214B helicopters. (c) Within 50 hours' time-in-service after the effective date of this AD and thereafter at intervals of 1,200 hours' time-in-service, inspect the yoke for straightness in accordance with the applicable maintenance manual. NOTE: BHTI Alert Service Bulletin No. 214-87-37, Revision A, dated September 10, 1987, pertains to this AD. (d) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Rotorcraft Certification Office, FAA, Rotorcraft Directorate, Fort Worth, Texas 76193-0170. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Certification Office. (e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished. (f) This amendment becomes effective on January 18, 1994. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_93-21-10.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-21-10 Document Type: AD Final Rules Docket Number: 91-ASW-18 Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters Subject: Main Rotor Yoke Assembly Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/18/1994 Make: Bell Helicopter Textron, Inc. Model: 214B | 214B-1 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: 93-21-10 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-ASW-18 AMENDMENT: 39-8724 AD NUMBER: 93-21-10 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. (BHTI) Model 214B and 214B-1 Helicopters ACTION: SUMMARY: DATES: Effective January 18, 1994. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-21-10 BELL HELICOPTER TEXTRON, INC. (BHTI): Amendment 39-8724. Docket Number 91-ASW-18. Applicability: Model 214B and 214B-1 helicopters, serial numbers (S/N's) 28001 through 28070, equipped with main rotor yoke assembly (assembly), part number (P/N) 214-010-105-001, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent failure of the assembly, loss of the main rotor, and subsequent loss of control of the helicopter, accomplish the following: (a) For assemblies that have 3,700 hours' or less time-in-service on the effective date of this airworthiness directive (AD), replace the assembly on or before reaching 3,750 hours' time-in-service. For assemblies that have more than 3,700 hours' time-in-service on the effective date of this AD, replace the assembly within the next 50 hours' time-in-service. (b) Within 50 hours' time-in-service after the effective date of this AD, install new airspeed versus altitude decals, P/N 214-075-256-105 for BHTI Model 214B-1 and P/N 214-075-256-107 for Model 214B helicopters. (c) Within 50 hours' time-in-service after the effective date of this AD and thereafter at intervals of 1,200 hours' time-in-service, inspect the yoke for straightness in accordance with the applicable maintenance manual. NOTE: BHTI Alert Service Bulletin No. 214-87-37, Revision A, dated September 10, 1987, pertains to this AD. (d) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Rotorcraft Certification Office, FAA, Rotorcraft Directorate, Fort Worth, Texas 76193-0170. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Certification Office. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Certification Office. (e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished. (f) This amendment becomes effective on January 18, 1994. FOOTER:
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