AD 73-12-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron Canada Limited | 206A | Airworthiness Directives; Bell Model 206A and 206B Helicopters |
| aircraft | Bell Helicopter Textron Canada Limited | 206A-1 (OH-58A) | Airworthiness Directives; Bell Model 206A and 206B Helicopters |
| aircraft | Bell Helicopter Textron Canada Limited | 206B | Airworthiness Directives; Bell Model 206A and 206B Helicopters |
| aircraft | Bell Helicopter Textron Canada Limited | 206B-1 | Airworthiness Directives; Bell Model 206A and 206B Helicopters |
Unsafe Condition
Fatigue cracks in the skin of the vertical fin in the area of the tail boom attachment, particularly aft of the upper rear attachment insert.
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Required Actions
Inspect the inboard skin of the vertical fin in the area of attachment for cracks, paying particular attention to the area aft of the upper rear attachment insert. Replace or repair the fin if cracks exceed 3.5 inches in length before further flight. If cracks are less than 3.5 inches, repair or replace per Bell Helicopter Company Service Letter No. 206-203, Revision C, or FAA-approved revision before further flight. Repeat inspections at intervals not exceeding 25 hours' time in service.
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Compliance Time
Within the next 25 hours' time in service after the effective date of this A.D., unless already accomplished within the last 25 hours' time in service
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Affected Aircraft
Bell Helicopter Textron Canada Limited Model 206A, 206A-1 (OH-58A), 206B, 206B-1 helicopters with serial numbers 4 through 865 and 867 through 873, equipped with vertical fin P/N 206-020-113-5, -7, or -9.
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Federal Register Abstract
Vertical Fin Skin Cracks
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_73-12-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-12-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 206A and 206B Helicopters Subject: Vertical Fin Skin Cracks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/01/1973 Make: Bell Helicopter Textron Canada Limited Model: 206A | 206A-1 (OH-58A) | 206B | 206B-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: 73-12-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1650 AD NUMBER: 73-12-01 SUBJECT HEADING: Airworthiness Directives; Bell Model 206A and 206B Helicopters ACTION: SUMMARY: DATES: Effective July 1, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-12-01 BELL: Amendment 39-1650. Applies to Model 206A and 206B helicopters, serial numbers 4 through 865 and 867 through 873, certificated in all categories, equipped with vertical fin, P/N 206-020-113-5, -7 and -9. Compliance required within the next 25 hours' time in service after the effective date of this A.D., unless already accomplished within the last 25 hours' time in service, and thereafter at intervals not to exceed 25 hours' time in service from the last inspection. To detect possible fatigue cracks in the skin of the vertical fin in the area of the tail boom attachment, accomplish the following: (a) Remove all tail fairing assemblies to gain access to the inboard side of the vertical fin assembly. (b) Visually inspect the inboard skin of the vertical fin in the area of attachment for any cracks, paying particular attention to the area aft of the upper rear attachment insert. (c) If any crack is found greater than 3.5 inches in length, remove and replace the fin before further flight. (d) If any crack is found less than 3.5 inches in length, remove and replace or repair the fin in accordance with Part II of Bell Helicopter Company Service Letter No. 206-203, Revision C, dated March 14, 1973, or later FAA approved revision, before further flight. (e) If no cracks are found, continue the repetitive inspections specified above. (f) This A.D. is no longer applicable when the fin is modified in accordance with Part I or II of Bell Helicopter Company Service Letter No. 206-203, Revision C, dated March 14, 1973, or later FAA approved revision. (Bell Helicopter Company Service Bulletin No. 206-01-73-1, dated January 9, 1973, pertains to this subject.) This amendment becomes effective July 1, 1973. FOOTER:
Document Text
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AD Final Rules - DRS_73-12-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 73-12-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Model 206A and 206B Helicopters Subject: Vertical Fin Skin Cracks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/01/1973 Make: Bell Helicopter Textron Canada Limited Model: 206A | 206A-1 (OH-58A) | 206B | 206B-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: 73-12-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1650 AD NUMBER: 73-12-01 SUBJECT HEADING: Airworthiness Directives; Bell Model 206A and 206B Helicopters ACTION: SUMMARY: DATES: Effective July 1, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 73-12-01 BELL: Amendment 39-1650. Applies to Model 206A and 206B helicopters, serial numbers 4 through 865 and 867 through 873, certificated in all categories, equipped with vertical fin, P/N 206-020-113-5, -7 and -9. Compliance required within the next 25 hours' time in service after the effective date of this A.D., unless already accomplished within the last 25 hours' time in service, and thereafter at intervals not to exceed 25 hours' time in service from the last inspection. To detect possible fatigue cracks in the skin of the vertical fin in the area of the tail boom attachment, accomplish the following: (a) Remove all tail fairing assemblies to gain access to the inboard side of the vertical fin assembly. (b) Visually inspect the inboard skin of the vertical fin in the area of attachment for any cracks, paying particular attention to the area aft of the upper rear attachment insert. (c) If any crack is found greater than 3.5 inches in length, remove and replace the fin before further flight. (d) If any crack is found less than 3.5 inches in length, remove and replace or repair the fin in accordance with Part II of Bell Helicopter Company Service Letter No. 206-203, Revision C, dated March 14, 1973, or later FAA approved revision, before further flight. (e) If no cracks are found, continue the repetitive inspections specified above. (f) This A.D. is no longer applicable when the fin is modified in accordance with Part I or II of Bell Helicopter Company Service Letter No. 206-203, Revision C, dated March 14, 1973, or later FAA approved revision. (Bell Helicopter Company Service Bulletin No. 206-01-73-1, dated January 9, 1973, pertains to this subject.) This amendment becomes effective July 1, 1973. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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