AD 91-05-13
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-7-1 | Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-100 | Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-101 | Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-102 | Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-103 | Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes |
Unsafe Condition
Possible malfunction of the wing flight spoilers due to outboard and inboard spigot fittings (Modification Nos. 7/1927, 7/1951, 7/1928, 7/1952).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Replace the outboard and inboard right and left wing flight spoilers spigot fittings within 180 days after the effective date, following Service Bulletins 7-27-25/Rev B and 7-27-26/Rev B. Alternate compliance may be approved by the Manager, New York ACO.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 180 days after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
de Havilland Model DHC-7 series airplanes, Serial Numbers 3 through 36, inclusive
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing Flight Spoilers
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-05-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-05-13 Document Type: AD Final Rules Docket Number: 90-NM-243-AD Subject Heading: Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes Subject: Wing Flight Spoilers Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/29/1991 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: 91-05-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-243-AD AMENDMENT: 39-6910 AD NUMBER: 91-05-13 SUBJECT HEADING: Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective March 29, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-05-13 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6910. Docket No. 90-NM-243-AD. Applicability: de Havilland Model DHC-7 series airplanes, Serial Numbers 3 through 36, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent possible malfunction of the wing flight spoilers, accomplish the following: A. Within 180 days after the effective date of this AD, replace the outboard (Modification Nos. 7/1927 and 7/1951) and inboard (Modification Nos. 7/1928 and 7/1952), right and left wing flight spoilers spigot fittings, in accordance with the Accomplishment Instructions in de Havilland Service Bulletins 7-27-25, Revision B, and 7-27-26, Revision B, both dated January 28, 1983. B. 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, New York Aircraft Certification Office (ACO), ANE-170, FAA, New England Region. NOTE: The request should be submitted directly to the Manager, New York ACO, ANE-170, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, New York ACO, ANE-170. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1YK, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York. This amendment (39-6910, AD 91-05-13) becomes effective on March 29, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-05-13.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-05-13 Document Type: AD Final Rules Docket Number: 90-NM-243-AD Subject Heading: Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes Subject: Wing Flight Spoilers Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 03/29/1991 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: 91-05-13 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 90-NM-243-AD AMENDMENT: 39-6910 AD NUMBER: 91-05-13 SUBJECT HEADING: Airworthiness Directives; Boeing Of Canada, Ltd., De Havilland Division Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective March 29, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-05-13 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6910. Docket No. 90-NM-243-AD. Applicability: de Havilland Model DHC-7 series airplanes, Serial Numbers 3 through 36, inclusive, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent possible malfunction of the wing flight spoilers, accomplish the following: A. Within 180 days after the effective date of this AD, replace the outboard (Modification Nos. 7/1927 and 7/1951) and inboard (Modification Nos. 7/1928 and 7/1952), right and left wing flight spoilers spigot fittings, in accordance with the Accomplishment Instructions in de Havilland Service Bulletins 7-27-25, Revision B, and 7-27-26, Revision B, both dated January 28, 1983. B. 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, New York Aircraft Certification Office (ACO), ANE-170, FAA, New England Region. NOTE: The request should be submitted directly to the Manager, New York ACO, ANE-170, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Manager, New York ACO, ANE-170. C. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1YK, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Valley Stream, New York. This amendment (39-6910, AD 91-05-13) becomes effective on March 29, 1991. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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