AD 89-26-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-7-1 | Airworthiness Directives; Boeing Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-100 | Airworthiness Directives; Boeing Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-101 | Airworthiness Directives; Boeing Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-102 | Airworthiness Directives; Boeing Model DHC-7 Series Airplanes |
| aircraft | Viking Air Limited | DHC-7-103 | Airworthiness Directives; Boeing Model DHC-7 Series Airplanes |
Unsafe Condition
Reduced structural capability of the fuselage and subsequent decompression of the airplane due to disbonding of fuselage skin doublers and loose/working rivets in specified areas.
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Required Actions
Perform low frequency ultrasonic inspections for disbonding of fuselage skin doublers and visual inspections for loose/working rivets in specified fuselage stations as per Service Bulletin 7-53-33. Repair loose rivets and disbonding prior to further flight. Report findings within 3 days to Transport Canada, manufacturer, and FAA. Alternate compliance may be approved by FAA Manager.
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Compliance Time
Within 60, 90, and 150 days after the effective date (January 14, 1990) for respective inspections (A, B, C). Reports due within 3 days after each inspection.
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Affected Aircraft
Boeing Model DHC-7 series airplanes, certificated in any category.
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Federal Register Abstract
Inspect Fuselage
Applicability Source Text
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AD Final Rules - DRS_89-26-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-26-07 Document Type: AD Final Rules Docket Number: 89-NM-161-AD Subject Heading: Airworthiness Directives; Boeing Model DHC-7 Series Airplanes Subject: Inspect Fuselage Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/14/1990 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| DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 89-26-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-161-AD AMENDMENT: 39-6422 AD NUMBER: 89-26-07 SUBJECT HEADING: Airworthiness Directives; Boeing Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective January 14, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-26-07 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39-6422. Docket No. 89-NM-161-AD. Applicability: All Model DHC-7 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural capability of the fuselage and subsequent decompression of the airplane, accomplish the following: A. Within 60 days after the effective date of this AD, perform the following inspections and repair, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage belly skin doublers, between fuselage stations X248.00 and X535.25 below stringer 20 left and right, in accordance with Inspection Part A of the service bulletin. 2. Visually inspect for looseness or working of the rivets in the vertical skin joints, at fuselage stations X535.25 and X576.25 below stringer 20, left and right. 3. Visually inspect for looseness or working of the rivets in the fuselage skin joints at station X630.00 around the complete periphery of the fuselage, above and below the passenger and emergency exit doors. 4. Visually inspect for looseness or working of the rivets in the skin longitudinal joint between fuselage stations X424.00 to X484.00 along stringer 20, left and right. Pay particular attention to the lower line of rivets. 5. Repair all loose rivets prior to further flight, in a manner approved by the Manager, New York Aircraft Certification Office, ANE-170, FAA, New England Region. 6. Repair all disbonding prior to further flight, in accordance with the service bulletin. B. Within 90 days after the effective date of this AD: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage left and right sidewall skin doublers, between fuselage stations X248.00 and X596.75, between stringer 20 and 10, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989. 2. Repair any disbonding prior to further flight, in accordance with the service bulletin. C. Within 150 days after the effective date of this AD: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage roof skin doublers between fuselage stations X248.00 and X630.00, between stringer 10, left and right, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989. 2. Repair any disbonding prior to further flight, in accordance with the service bulletin. D. Within 3 days after accomplishing each of the inspections required by paragraphs A., B., and C., above, report all findings, positive or negative, to the Director, Airworthiness Branch, Transport Canada, Ottawa, Canada; to the manufacturer, Boeing of Canada, Ltd., de Havilland Division, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989; and to the FAA, Manager, New York Aircraft Certification Office, ANE-170, New England Region. E. 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, ANE-170, FAA, New England Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, New York Aircraft Certification Office, ANE-170. F. 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 1Y5, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or New York Aircraft Certification Office, FAA, New England Region, 181 South Franklin Avenue, Valley Stream, New York. This amendment (39-6422, AD 89-26-07) becomes effective on January 14, 1990. FOOTER:
Document Text
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AD Final Rules - DRS_89-26-07.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 89-26-07 Document Type: AD Final Rules Docket Number: 89-NM-161-AD Subject Heading: Airworthiness Directives; Boeing Model DHC-7 Series Airplanes Subject: Inspect Fuselage Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 01/14/1990 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: 89-26-07 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 89-NM-161-AD AMENDMENT: 39-6422 AD NUMBER: 89-26-07 SUBJECT HEADING: Airworthiness Directives; Boeing Model DHC-7 Series Airplanes ACTION: SUMMARY: DATES: Effective January 14, 1990. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 89-26-07 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39-6422. Docket No. 89-NM-161-AD. Applicability: All Model DHC-7 series airplanes, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To prevent reduced structural capability of the fuselage and subsequent decompression of the airplane, accomplish the following: A. Within 60 days after the effective date of this AD, perform the following inspections and repair, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage belly skin doublers, between fuselage stations X248.00 and X535.25 below stringer 20 left and right, in accordance with Inspection Part A of the service bulletin. 2. Visually inspect for looseness or working of the rivets in the vertical skin joints, at fuselage stations X535.25 and X576.25 below stringer 20, left and right. 3. Visually inspect for looseness or working of the rivets in the fuselage skin joints at station X630.00 around the complete periphery of the fuselage, above and below the passenger and emergency exit doors. 4. Visually inspect for looseness or working of the rivets in the skin longitudinal joint between fuselage stations X424.00 to X484.00 along stringer 20, left and right. Pay particular attention to the lower line of rivets. 5. Repair all loose rivets prior to further flight, in a manner approved by the Manager, New York Aircraft Certification Office, ANE-170, FAA, New England Region. 6. Repair all disbonding prior to further flight, in accordance with the service bulletin. B. Within 90 days after the effective date of this AD: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage left and right sidewall skin doublers, between fuselage stations X248.00 and X596.75, between stringer 20 and 10, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989. 2. Repair any disbonding prior to further flight, in accordance with the service bulletin. C. Within 150 days after the effective date of this AD: 1. Perform a low frequency ultrasonic inspection for disbonding of the fuselage roof skin doublers between fuselage stations X248.00 and X630.00, between stringer 10, left and right, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989. 2. Repair any disbonding prior to further flight, in accordance with the service bulletin. D. Within 3 days after accomplishing each of the inspections required by paragraphs A., B., and C., above, report all findings, positive or negative, to the Director, Airworthiness Branch, Transport Canada, Ottawa, Canada; to the manufacturer, Boeing of Canada, Ltd., de Havilland Division, in accordance with de Havilland Service Bulletin 7-53-33, Revision A, dated June 9, 1989; and to the FAA, Manager, New York Aircraft Certification Office, ANE-170, New England Region. E. 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, ANE-170, FAA, New England Region. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, New York Aircraft Certification Office, ANE-170. F. 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 1Y5, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or New York Aircraft Certification Office, FAA, New England Region, 181 South Franklin Avenue, Valley Stream, New York. This amendment (39-6422, AD 89-26-07) becomes effective on January 14, 1990. FOOTER:
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