AD 90-01-11
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron, Inc. | 204B | Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 204B Helicopters |
Unsafe Condition
Failure of the tail rotor duplex bearing set, P/N 204-040-424-001, could result in loss of tail rotor control and subsequent loss of the helicopter.
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Required Actions
Remove the tail rotor gearbox duplex bearing set, P/N 204-040-424-001, within 100 hours' time in service after the effective date and replace with a serviceable part before further flight. The helicopter may be flown to a base where AD requirements can be accomplished with FAA approval.
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Compliance Time
within 100 hours' time in service after the effective date of this AD
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Affected Aircraft
Bell Helicopter Textron, Inc. Model 204B helicopters with tail rotor gearbox duplex bearing sets P/N 204-040-424-001, serial numbers 1 thru 182, MB183 thru MB382, MB442, MB486, MB513, MB518, MB519, MB524, MB530, MB531, MB544, MB545, MB548, MB549, MB551, MB553, MB554, MB561, MB659, MB743, MB744, MB760 thru MB769, and MB927 thru MB936.
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Federal Register Abstract
Tail Rotor Gearbox Bearing Set
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_90-01-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-01-11 Document Type: AD Final Rules Docket Number: 89-ASW-50 Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 204B Helicopters Subject: Tail Rotor Gearbox Bearing Set Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/01/1990 Make: Bell Helicopter Textron, Inc. Model: 204B Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 90-01-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-ASW-50 AMENDMENT: 39-6450 AD NUMBER: 90-01-11 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 204B Helicopters ACTION: SUMMARY: DATES: Effective February 1, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-01-11 BELL HELICOPTER TEXTRON, INC.: Amendment 39-6450. Docket No. 89-ASW-50. Applicability: Bell Helicopter Textron, Inc., Model 204B helicopters, certificated in any category, with tail rotor gearbox duplex bearing sets, P/N 204-040-424-001, with serial numbers (S/N's) 1 thru 182, MB183 thru MB382, MB442, MB486, MB513, MB518, MB519, MB524, MB530, MB531, MB544, MB545, MB548, MB549, MB551, MB553, MB554, MB561, MB659, MB743, MB744, MB760 thru MB769 and MB927 thru MB936, installed in tail rotor gearbox output quill, P/N 204-040-012-009. Compliance: Required as indicated, unless already accomplished. To prevent failure of the tail rotor duplex bearing which could result in loss of tail rotor control and subsequent loss of the helicopter, accomplish the following: (a) Within the next 100 hours' time in service after the effective date of this AD, remove the tail rotor gearbox duplex bearing set, P/N 204-040-424-001, from service and replace with a serviceable part before further flight. (b) In accordance with FAR Sections 21.197 and 21.199, the helicopter may be flown to a base where the requirements of this AD may be accomplished. (c) An alternate 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, ASW-170, Rotorcraft Directorate, FAA, Southwest Region, Fort Worth, Texas. This amendment (39-6450, AD 90-01-11) becomes effective on February 1, 1990. FOOTER:
Document Text
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AD Final Rules - DRS_90-01-11.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 90-01-11 Document Type: AD Final Rules Docket Number: 89-ASW-50 Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 204B Helicopters Subject: Tail Rotor Gearbox Bearing Set Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 02/01/1990 Make: Bell Helicopter Textron, Inc. Model: 204B 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: 90-01-11 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-ASW-50 AMENDMENT: 39-6450 AD NUMBER: 90-01-11 SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 204B Helicopters ACTION: SUMMARY: DATES: Effective February 1, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 90-01-11 BELL HELICOPTER TEXTRON, INC.: Amendment 39-6450. Docket No. 89-ASW-50. Applicability: Bell Helicopter Textron, Inc., Model 204B helicopters, certificated in any category, with tail rotor gearbox duplex bearing sets, P/N 204-040-424-001, with serial numbers (S/N's) 1 thru 182, MB183 thru MB382, MB442, MB486, MB513, MB518, MB519, MB524, MB530, MB531, MB544, MB545, MB548, MB549, MB551, MB553, MB554, MB561, MB659, MB743, MB744, MB760 thru MB769 and MB927 thru MB936, installed in tail rotor gearbox output quill, P/N 204-040-012-009. Compliance: Required as indicated, unless already accomplished. To prevent failure of the tail rotor duplex bearing which could result in loss of tail rotor control and subsequent loss of the helicopter, accomplish the following: (a) Within the next 100 hours' time in service after the effective date of this AD, remove the tail rotor gearbox duplex bearing set, P/N 204-040-424-001, from service and replace with a serviceable part before further flight. (b) In accordance with FAR Sections 21.197 and 21.199, the helicopter may be flown to a base where the requirements of this AD may be accomplished. (c) An alternate 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, ASW-170, Rotorcraft Directorate, FAA, Southwest Region, Fort Worth, Texas. This amendment (39-6450, AD 90-01-11) becomes effective on February 1, 1990. FOOTER:
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