AD 71-18-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Helicopter Textron Canada Limited | 206A | Airworthiness Directives; Bell Models 206A and 206B Helicopters |
| aircraft | Bell Helicopter Textron Canada Limited | 206B | Airworthiness Directives; Bell Models 206A and 206B Helicopters |
Unsafe Condition
Corrosion and fatigue cracks in the main rotor blade spar lower surface adjacent to the tip inertia weight attachment screws.
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Required Actions
Inspect the lower surface of the main rotor blade from station 170 to 180 for paint blisters, raised areas, paint cracks, and exposed metal. If corrosion or cracks are found, remove and replace the blade or follow repair instructions. Perform repetitive inspections at intervals not exceeding 100 or 25 hours time in service depending on initial compliance.
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Compliance Time
Within 25 hours time in service from May 5, 1971 for blades with 600+ hours, or before reaching 625 hours for those with less than 600 hours. Repetitive inspections at intervals not more than 100 or 25 hours time in service.
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Affected Aircraft
Bell Helicopter Textron Canada Limited Models 206A and 206B equipped with main rotor blades P/N 206-010-200-29.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Main Rotor Blade Spar
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-18-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-18-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Models 206A and 206B Helicopters Subject: Main Rotor Blade Spar Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/03/1973 Make: Bell Helicopter Textron Canada Limited Model: 206A | 206B Product Type: Aircraft Product Subtype: Rotorcraft Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 71-18-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1692 AD NUMBER: 71-18-04 SUBJECT HEADING: Airworthiness Directives; Bell Models 206A and 206B Helicopters ACTION: SUMMARY: DATES: Effective September 3, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-18-04 BELL: Amdt. 39-1280 as amended by Amendment 39-1692. Applies to Bell Models 206A and 206B helicopters certificated in all categories, equipped with main rotor blades, P/N 206-010-200-29. Compliance required as indicated. To detect and prevent possible corrosion and fatigue cracks in the main rotor blade spar lower surface adjacent to the tip inertia weight attachment screws, accomplish following: (a) Inspect those main rotor blades having 600 or more hours total time in service on May 5, 1971 within 25 hours time in service therefrom, unless already accomplished in accordance with paragraph (c). (b) Inspect those main rotor blades having less than 600 hours time in service on May 5, 1971 before reaching 625 hours total time in service in accordance with paragraph (c). (c) Visually inspect the lower surface of the blade from blade station 170 to 180 in the area of the screw heads for paint blisters, raised areas, paint cracks and for exposed metal and accomplish repetitive inspections at intervals of not more than 100 hours time in service from the last inspection. (1) If paint blisters, raised areas or paint cracks are found, remove the finish in accordance with the instructions of Item 3.c of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971 or later FAA approved revision, and inspect for corrosion and cracks in the spar adjacent to the screw heads using a dye penetrant or equivalent inspection method. (i) If cracks are found, remove and replace the blade before further flight. (ii) If corrosion is found, follow repair and limitation instructions on page 2-18A, paragraph 2-16, subparagraph e(3) in the Model 206A Maintenance and Overhaul Manual as revised October 15, 1970 or FAA approved equivalent. (iii) If no corrosion or cracks are found, treat and refinish the exposed or unpainted area in accordance with Item 4.b(1) of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971, or later FAA approved revision. (2) If no paint blisters, raised areas or paint cracks are found but exposed metal is found, treat exposed area in accordance with paragraph 4.b(2) of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971, or later FAA approved revision. (d) Visually inspect the lower surface of the blade from blade station 170 to 180 in the area of the screw heads for paint blisters, raised areas, paint cracks and for exposed metal and accomplish repetitive inspections at intervals of not more than 25 hours time in service from the last inspection. (1) If paint blisters, raised areas or paint cracks are found, the inspections and surface treatment of subparagraph (c) (1) are required. (2) If only exposed metal is found, clean, rinse and dry the surface and apply non-siliconized wax to the exposed metal. (3) The inspections and waxing specified in paragraph (d) may be performed by the pilot. NOTE: For the requirements regarding listing of compliance and method of compliance with this AD in the aircraft maintenance record, see FAR 91.173. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to the Service Manager, Bell Helicopter Company, P. O. Box 482, Fort Worth, Texas 76101. These documents may also be examined at the Office of the Regional Counsel, Southwest Region, FAA, 4400 Blue Mound Road, Fort Worth, Texas, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its headquarters in Washington, D.C. and at the Southwest Regional Office in Fort Worth, Texas. This AD, Amendment 39-1280 supersedes Amendment 39-1182 (36 F.R. 6740), AD 71- 07-03. Amendment 39-1280 became effective September 3, 1971. This amendment 39-1692 becomes effective September 3, 1973. FOOTER:
Document Text
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AD Final Rules - DRS_71-18-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-18-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Bell Models 206A and 206B Helicopters Subject: Main Rotor Blade Spar Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/03/1973 Make: Bell Helicopter Textron Canada Limited Model: 206A | 206B 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: 71-18-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1692 AD NUMBER: 71-18-04 SUBJECT HEADING: Airworthiness Directives; Bell Models 206A and 206B Helicopters ACTION: SUMMARY: DATES: Effective September 3, 1973. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-18-04 BELL: Amdt. 39-1280 as amended by Amendment 39-1692. Applies to Bell Models 206A and 206B helicopters certificated in all categories, equipped with main rotor blades, P/N 206-010-200-29. Compliance required as indicated. To detect and prevent possible corrosion and fatigue cracks in the main rotor blade spar lower surface adjacent to the tip inertia weight attachment screws, accomplish following: (a) Inspect those main rotor blades having 600 or more hours total time in service on May 5, 1971 within 25 hours time in service therefrom, unless already accomplished in accordance with paragraph (c). (b) Inspect those main rotor blades having less than 600 hours time in service on May 5, 1971 before reaching 625 hours total time in service in accordance with paragraph (c). (c) Visually inspect the lower surface of the blade from blade station 170 to 180 in the area of the screw heads for paint blisters, raised areas, paint cracks and for exposed metal and accomplish repetitive inspections at intervals of not more than 100 hours time in service from the last inspection. (1) If paint blisters, raised areas or paint cracks are found, remove the finish in accordance with the instructions of Item 3.c of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971 or later FAA approved revision, and inspect for corrosion and cracks in the spar adjacent to the screw heads using a dye penetrant or equivalent inspection method. (i) If cracks are found, remove and replace the blade before further flight. (ii) If corrosion is found, follow repair and limitation instructions on page 2-18A, paragraph 2-16, subparagraph e(3) in the Model 206A Maintenance and Overhaul Manual as revised October 15, 1970 or FAA approved equivalent. (iii) If no corrosion or cracks are found, treat and refinish the exposed or unpainted area in accordance with Item 4.b(1) of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971, or later FAA approved revision. (2) If no paint blisters, raised areas or paint cracks are found but exposed metal is found, treat exposed area in accordance with paragraph 4.b(2) of Bell Helicopter Company Service Bulletin No. 206A-19, Revision A, dated March 12, 1971, or later FAA approved revision. (d) Visually inspect the lower surface of the blade from blade station 170 to 180 in the area of the screw heads for paint blisters, raised areas, paint cracks and for exposed metal and accomplish repetitive inspections at intervals of not more than 25 hours time in service from the last inspection. (1) If paint blisters, raised areas or paint cracks are found, the inspections and surface treatment of subparagraph (c) (1) are required. (2) If only exposed metal is found, clean, rinse and dry the surface and apply non-siliconized wax to the exposed metal. (3) The inspections and waxing specified in paragraph (d) may be performed by the pilot. NOTE: For the requirements regarding listing of compliance and method of compliance with this AD in the aircraft maintenance record, see FAR 91.173. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to the Service Manager, Bell Helicopter Company, P. O. Box 482, Fort Worth, Texas 76101. These documents may also be examined at the Office of the Regional Counsel, Southwest Region, FAA, 4400 Blue Mound Road, Fort Worth, Texas, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its headquarters in Washington, D.C. and at the Southwest Regional Office in Fort Worth, Texas. This AD, Amendment 39-1280 supersedes Amendment 39-1182 (36 F.R. 6740), AD 71- 07-03. Amendment 39-1280 became effective September 3, 1971. This amendment 39-1692 becomes effective September 3, 1973. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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