AD 83-22-51
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 bonding between the skin and honeycomb core of wing inner and mid fuel tank covers P/N 75710059-007 thru -014 and P/N 75711708-003 thru -006 could result in loss of strength and stiffness of the wing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect upper surfaces of wing inner and mid fuel tank covers using ultrasonic tester or coin test. Replace covers with unbonded surfaces before further flight. Repetitive inspections may be terminated with installation of P/N 7Z4096-001 (Inner) and P/N 7Z4097-001 (Middle).
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Compliance Time
within the next 10 hours time in service, unless previously accomplished within the past 490 hours and thereafter at intervals not to exceed 500 hours time in service from the last inspection
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
DeHavilland Model DHC-7 airplanes Serial Numbers 3 through 27 with wing fuel tank covers P/N 75710059-007 thru -014 (Inner) and P/N 75711708-003 thru -006 (Middle)
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Wing and Mid Fuel Tank Inspection
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_83-22-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 83-22-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Wing and Mid Fuel Tank Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/29/1984 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: 83-22-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4865 AD NUMBER: 83-22-51 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective May 29, 1984. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 83-22-51 DeHAVILLAND: Amendment 39-4865. Applies to DeHavilland Model DHC-7 airplanes Serial Numbers 3 through 27 certificated in all categories fitted with wing fuel tank covers P/N's 75710059-007 thru -014 (Inner) and P/N's 75711708-003 thru -006 (Middle). To detect failure of the bonding which could result in a loss of strength and stiffness of the wing, accomplish the following within the next 10 hours time in service, unless previously accomplished within the past 490 hours and thereafter at intervals not to exceed 500 hours time in service from the last inspection: A. Inspect the upper surfaces of the wing inner and mid fuel tank covers P/N 75710059-007 thru -014 and P/N 75711708-003 thru -006, respectively, for a bond failure between the skin and honeycomb core by: 1. Using a calibrated portable ultrasonic tester over the total upper surface of each cover; or 2. Conducting a coin test (at approximately one inch intervals) over the total upper surface of each cover. (The coin test detects unbonded areas by the change in audible response when the surface is systematically tapped with a coin.) NOTE: Tests may be accomplished with covers installed on aircraft. B. Replace covers found to have unbonded surfaces with serviceable covers prior to further flight. C. The repetitive inspections required by this AD may be terminated upon the installation of fuel tank covers P/N 7Z4096-001 (Inner) and P/N 7Z4097-001 (Middle). D. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, FAA, New England Region. E. 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 May 29, 1984, and was effective earlier to those recipients of telegraph AD T83-22-51, dated October 27, 1983. FOOTER:
Document Text
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AD Final Rules - DRS_83-22-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 83-22-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Wing and Mid Fuel Tank Inspection Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/29/1984 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: 83-22-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4865 AD NUMBER: 83-22-51 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective May 29, 1984. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 83-22-51 DeHAVILLAND: Amendment 39-4865. Applies to DeHavilland Model DHC-7 airplanes Serial Numbers 3 through 27 certificated in all categories fitted with wing fuel tank covers P/N's 75710059-007 thru -014 (Inner) and P/N's 75711708-003 thru -006 (Middle). To detect failure of the bonding which could result in a loss of strength and stiffness of the wing, accomplish the following within the next 10 hours time in service, unless previously accomplished within the past 490 hours and thereafter at intervals not to exceed 500 hours time in service from the last inspection: A. Inspect the upper surfaces of the wing inner and mid fuel tank covers P/N 75710059-007 thru -014 and P/N 75711708-003 thru -006, respectively, for a bond failure between the skin and honeycomb core by: 1. Using a calibrated portable ultrasonic tester over the total upper surface of each cover; or 2. Conducting a coin test (at approximately one inch intervals) over the total upper surface of each cover. (The coin test detects unbonded areas by the change in audible response when the surface is systematically tapped with a coin.) NOTE: Tests may be accomplished with covers installed on aircraft. B. Replace covers found to have unbonded surfaces with serviceable covers prior to further flight. C. The repetitive inspections required by this AD may be terminated upon the installation of fuel tank covers P/N 7Z4096-001 (Inner) and P/N 7Z4097-001 (Middle). D. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, New York Aircraft Certification Office, FAA, New England Region. E. 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 May 29, 1984, and was effective earlier to those recipients of telegraph AD T83-22-51, dated October 27, 1983. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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