AD 71-11-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-6-1 | Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-100 | Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-200 | Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes |
| aircraft | Viking Air Limited | DHC-6-300 | Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes |
Unsafe Condition
The circuit wires in certain de Havilland DHC-6 series airplanes lack adequate protection, which could result in electrical circuit failure.
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Required Actions
Incorporate specified DHC Modifications (Nos. 6/1369, 6/1370, 6/1371, 6/1372, 6/1389) as per Service Bulletin 6/245. Exclusions apply for specific serial numbers. Equivalent alterations may be used with FAA approval.
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Compliance Time
within the next 500 hours time in service after the effective date of this AD unless already accomplished
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Affected Aircraft
de Havilland Model DHC-6-1, DHC-6-100, DHC-6-200, DHC-6-300 airplanes with serial numbers 1 through 289, excluding specific serial numbers 176, 221, 233, 268, and 286 as applicable per modification
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Federal Register Abstract
Protection for Circuit Wires
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_71-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes Subject: Protection for Circuit Wires Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/19/1971 Make: Viking Air Limited Model: DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 71-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1212 AD NUMBER: 71-11-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes ACTION: SUMMARY: DATES: Effective May 19, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-11-01 De HAVILLAND AIRCRAFT OF CANADA, LIMITED: Amdt. 39-1212. Applies to de Havilland Model DHC-6 Airplanes certificated in all categories. Compliance required within the next 500 hours time in service after the effective date of this AD unless already accomplished. To provide adequate protection for particular circuit wires, accomplish the following in accordance with the instructions contained in DHC Service Bulletin No. 6/245 dated October 9, 1970: (a) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1369; (b) Alter airplanes, S/Ns 1 through 289, except S/Ns 176, 233, 268, and 286, by incorporating DHC Modification No. 6/1370; (c) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1371. Modification No. 6/1371 is applicable only to those airplanes in which DHC Modification No. 6/1053 has been incorporated; (d) Alter airplanes, S/Ns 136 through 289, except S/Ns 176, 221, 233, 268, and 286, by incorporating DHC Modification No. 6/1372; (e) Alter airplanes, S/Ns 136 through 289, by incorporating DHC Modification No. 6/1389. Equivalent alterations may be used provided they are approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Upon request with substantiation data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective May 19, 1971. FOOTER:
Document Text
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AD Final Rules - DRS_71-11-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 71-11-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes Subject: Protection for Circuit Wires Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/19/1971 Make: Viking Air Limited Model: DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 71-11-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-1212 AD NUMBER: 71-11-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Model DHC-6 Series Airplanes ACTION: SUMMARY: DATES: Effective May 19, 1971. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 71-11-01 De HAVILLAND AIRCRAFT OF CANADA, LIMITED: Amdt. 39-1212. Applies to de Havilland Model DHC-6 Airplanes certificated in all categories. Compliance required within the next 500 hours time in service after the effective date of this AD unless already accomplished. To provide adequate protection for particular circuit wires, accomplish the following in accordance with the instructions contained in DHC Service Bulletin No. 6/245 dated October 9, 1970: (a) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1369; (b) Alter airplanes, S/Ns 1 through 289, except S/Ns 176, 233, 268, and 286, by incorporating DHC Modification No. 6/1370; (c) Alter airplanes, S/Ns 6 through 289, except S/Ns 176, 221, 233, 268 and 286, by incorporating DHC Modification No. 6/1371. Modification No. 6/1371 is applicable only to those airplanes in which DHC Modification No. 6/1053 has been incorporated; (d) Alter airplanes, S/Ns 136 through 289, except S/Ns 176, 221, 233, 268, and 286, by incorporating DHC Modification No. 6/1372; (e) Alter airplanes, S/Ns 136 through 289, by incorporating DHC Modification No. 6/1389. Equivalent alterations may be used provided they are approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Upon request with substantiation data submitted through an FAA maintenance inspector, the compliance time specified in this AD may be increased by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. This amendment is effective May 19, 1971. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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