AD 89-26-07

final rule

Airworthiness Directives; Boeing Model DHC-7 Series Airplanes

AD Number
89-26-07
Status
final_rule
Effective Date
Product Category
aircraft
Docket
89-NM-161-AD
FR Citation
This information is not available.
Technical illustration of a riveted aircraft structural panel and frame
Problem area Airframe structure

Applicability

TypeManufacturerModelDetails
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.

AI-generated summary from the source AD text. Verify against the official source before acting.

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.

AI-generated summary from the source AD text. Verify against the official source before acting.

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.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Boeing Model DHC-7 series airplanes, certificated in any category.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Inspect Fuselage

Applicability Source Text

Show captured applicability text from the source AD
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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

Show stored source text (verify against official source)
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:

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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