AD 86-16-11 L
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron, Inc. | 412 | Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 412 Helicopters |
Unsafe Condition
Failure of the tail rotor control due to cracks in the T/R trunnion housing P/N 212-011-716-1 or axial play in the T/R trunnion, or presence of excess balance washers.
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Required Actions
Visually inspect the T/R hub assembly P/N 212-011-701-3 per Part I of BHTI ASB 412-86-25. If cracks, axial play, or excess washers exist, perform Part II of the ASB before further flight. Repeat inspections every 20 hours' time in service until paragraph (b) is done. Inspect trunnion bearing housing P/N 212-011-716-1 per Part II of the ASB within 150 hours' time in service or 60 days after AD issue, replacing housings with end web thickness ≤0.059 inches.
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Compliance Time
Within 20 hours' time in service after receipt of this AD for initial inspection. For paragraph (b), within 150 hours' time in service or within 60 days after the issue date of this AD, whichever occurs first.
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Affected Aircraft
Bell Helicopter Textron, Inc. Model 412 helicopters, serial numbers 33001 through 33118, 33120 and 33121, certified in any category.
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Federal Register Abstract
Inspect T/R Hub Assembly (See 90-03-09)
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-16-11_L.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-16-11 L Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 412 Helicopters Subject: Inspect T/R Hub Assembly (See 90-03-09) Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Bell Helicopter Textron, Inc. Model: 412 Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 86-16-11 L CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 86-16-11 L SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 412 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-16-11 BELL HELICOPTER TEXTRON, INC.: Letter issued August 12, 1986. Applies to all Bell Helicopter Model 412 helicopters, S/N 33001 through 33118, 33120 and 33121, certified in any category. Compliance required as indicated unless already accomplished. To prevent failure of the tail rotor control, accomplish the following: (a) Within 20 hours' time in service after receipt of this AD, visually inspect the T/R hub assembly P/N 212-011-701-3, in accordance with Part I of Bell Helicopter Textron, Inc. (BHTI), Alert Service Bulletin (ASB) 412-86-25, Revision "A," dated July 23,1986. (1) If the (P/N) 212-011-716-1 T/R trunnion housing is cracked or there is axial play in the T/R trunnion, or if there are excess balance washers, comply with Part II of the Alert Service Bulletin before further flight. (2) Repeat this inspection every 20 hours' time in service until paragraph (b) of this AD is accomplished. (b) Remove the 212-011-701-1 T/R hub and blade assembly and inspect the trunnion bearing housing, P/N 212-011-716-1, as detailed in Part II of BHTI ASB 412-86-25, Revision "A," dated July 23, 1986, within 150 hours' time in service or within 60 days after the issue date of this AD, whichever occurs first. Replace any housing having an end web thickness of .059 inches or less with a serviceable part. An alternate method of compliance or adjustment of the compliance time, which provides an equivalent level of safety, may be approved by the Manager, Helicopter Certification Branch, Aircraft Certification Division, FAA, Southwest Region. This airworthiness directive becomes effective upon receipt. FOOTER:
Document Text
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AD Final Rules - DRS_86-16-11_L.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-16-11 L Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 412 Helicopters Subject: Inspect T/R Hub Assembly (See 90-03-09) Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Bell Helicopter Textron, Inc. Model: 412 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: 86-16-11 L CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 86-16-11 L SUBJECT HEADING: Airworthiness Directives; BELL HELICOPTER TEXTRON, INC. Model 412 Helicopters ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-16-11 BELL HELICOPTER TEXTRON, INC.: Letter issued August 12, 1986. Applies to all Bell Helicopter Model 412 helicopters, S/N 33001 through 33118, 33120 and 33121, certified in any category. Compliance required as indicated unless already accomplished. To prevent failure of the tail rotor control, accomplish the following: (a) Within 20 hours' time in service after receipt of this AD, visually inspect the T/R hub assembly P/N 212-011-701-3, in accordance with Part I of Bell Helicopter Textron, Inc. (BHTI), Alert Service Bulletin (ASB) 412-86-25, Revision "A," dated July 23,1986. (1) If the (P/N) 212-011-716-1 T/R trunnion housing is cracked or there is axial play in the T/R trunnion, or if there are excess balance washers, comply with Part II of the Alert Service Bulletin before further flight. (2) Repeat this inspection every 20 hours' time in service until paragraph (b) of this AD is accomplished. (b) Remove the 212-011-701-1 T/R hub and blade assembly and inspect the trunnion bearing housing, P/N 212-011-716-1, as detailed in Part II of BHTI ASB 412-86-25, Revision "A," dated July 23, 1986, within 150 hours' time in service or within 60 days after the issue date of this AD, whichever occurs first. Replace any housing having an end web thickness of .059 inches or less with a serviceable part. An alternate method of compliance or adjustment of the compliance time, which provides an equivalent level of safety, may be approved by the Manager, Helicopter Certification Branch, Aircraft Certification Division, FAA, Southwest Region. This airworthiness directive becomes effective upon receipt. FOOTER:
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