AD 86-15-05
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-7-1 | Airworthiness Directives; DeHavilland Model DHC-7 Airplanes |
| aircraft | Viking Air Limited | DHC-7-100 | Airworthiness Directives; DeHavilland Model DHC-7 Airplanes |
| aircraft | Viking Air Limited | DHC-7-101 | Airworthiness Directives; DeHavilland Model DHC-7 Airplanes |
| aircraft | Viking Air Limited | DHC-7-102 | Airworthiness Directives; DeHavilland Model DHC-7 Airplanes |
| aircraft | Viking Air Limited | DHC-7-103 | Airworthiness Directives; DeHavilland Model DHC-7 Airplanes |
Unsafe Condition
Loss of the 400 Hz AC electrical power system could result in improper crew warning.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Modify the 400 Hz AC system in accordance with DeHavilland Service Bulletin 7-24-13, Revision A, dated September 10, 1982. An alternate means of compliance or adjustment of the compliance time may be used if approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within 60 days after the effective date of this AD, unless previously accomplished
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
DeHavilland Model DHC-7 airplanes, serial numbers 1 through 14 inclusive
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Electrical Power System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_86-15-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-15-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Electrical Power System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/04/1986 Make: Viking Air Limited Model: DHC-7-1 | DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 86-15-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5357 AD NUMBER: 86-15-05 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective September 4, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-15-05 DEHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-5357. Applies to Model DHC-7 airplanes, serial numbers 1 through 14 inclusive, certificated in any category. Compliance is required within 60 days after the effective date of this AD, unless previously accomplished. To assure proper crew warning in the event of the loss of the 400 Hz AC electrical power system, accomplish the following: 1. Modify the 400 Hz AC system in accordance with DeHavilland Service Bulletin 7-24-13, Revision A, dated September 10, 1982. 2. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region. 3. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. All persons affected by this directive, who have not already received the appropriate service bulletin from the manufacturer, may obtain copies upon request to DeHavilland Aircraft of Canada, Ltd., Downsview, Ontario M3K 1Y5, Canada. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective September 4, 1986. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_86-15-05.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 86-15-05 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Electrical Power System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/04/1986 Make: Viking Air Limited Model: DHC-7-1 | DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large 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: 86-15-05 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-5357 AD NUMBER: 86-15-05 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective September 4, 1986. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 86-15-05 DEHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-5357. Applies to Model DHC-7 airplanes, serial numbers 1 through 14 inclusive, certificated in any category. Compliance is required within 60 days after the effective date of this AD, unless previously accomplished. To assure proper crew warning in the event of the loss of the 400 Hz AC electrical power system, accomplish the following: 1. Modify the 400 Hz AC system in accordance with DeHavilland Service Bulletin 7-24-13, Revision A, dated September 10, 1982. 2. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Standardization Branch, ANM-113, FAA, Northwest Mountain Region. 3. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD. All persons affected by this directive, who have not already received the appropriate service bulletin from the manufacturer, may obtain copies upon request to DeHavilland Aircraft of Canada, Ltd., Downsview, Ontario M3K 1Y5, Canada. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective September 4, 1986. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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