AD 83-21-03
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
Failure of the pilot valve of the ground spoiler valve No. 2 could result in uncommanded operation of the ground spoilers during flight, leading to potential loss of control.
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Required Actions
Perform an operational check of the ground spoiler system within 25 flight hours from the AD effective date, and repeat the functional checks every 800 flight hours. Use DeHavilland Alert Service Bulletin A7-27-56 for instructions. Alternate means of compliance may be approved.
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Compliance Time
Within 25 flight hours from the effective date of this AD
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Affected Aircraft
DeHavilland model DHC-7 airplanes equipped with ground spoiler valves per modification No. 7/1732, including DHC-7-1, DHC-7-100, DHC-7-101, DHC-7-102, DHC-7-103 models.
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Federal Register Abstract
Ground Spoiler System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_83-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 83-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Ground Spoiler System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/02/1983 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| DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 83-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4753 AD NUMBER: 83-21-03 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective November 2, 1983. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 83-21-03 DEHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-4753. Applies to DeHavilland model DHC-7 airplanes, certificated in all categories, which are equipped with ground spoiler valves installed in accordance with DeHavilland modification No. 7/1732. To detect failures of the pilot valve of the ground spoiler valve No. 2, accomplish the following, unless previously accomplished: A. Within 25 flight hours from the effective date of this AD, perform an operational check of the ground spoiler system, and take appropriate corrective action, if necessary, in accordance with the Accomplishment Instructions of DeHavilland Aircraft of Canada, Ltd., Alert Service Bulletin A7-27-56, dated June 28, 1983. B. Repeat the functional checks of paragraph A. at intervals not to exceed 800 flight hours. C. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. D. 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. This amendment becomes effective November 2, 1983. FOOTER:
Document Text
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AD Final Rules - DRS_83-21-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 83-21-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Ground Spoiler System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/02/1983 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: 83-21-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4753 AD NUMBER: 83-21-03 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective November 2, 1983. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 83-21-03 DEHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-4753. Applies to DeHavilland model DHC-7 airplanes, certificated in all categories, which are equipped with ground spoiler valves installed in accordance with DeHavilland modification No. 7/1732. To detect failures of the pilot valve of the ground spoiler valve No. 2, accomplish the following, unless previously accomplished: A. Within 25 flight hours from the effective date of this AD, perform an operational check of the ground spoiler system, and take appropriate corrective action, if necessary, in accordance with the Accomplishment Instructions of DeHavilland Aircraft of Canada, Ltd., Alert Service Bulletin A7-27-56, dated June 28, 1983. B. Repeat the functional checks of paragraph A. at intervals not to exceed 800 flight hours. C. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region. D. 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. This amendment becomes effective November 2, 1983. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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