AD 81-03-51
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
Disengagement of the lock nut could cause damage to the flap system.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect flap screw jack tracks 2 and 3 for correct locking feature of lock washer against the dome nut, ensuring the cup lock washer P/N MS9952-08 is tapped into groove of lock nut P/N 24156-1. Lubricate the aft end bearing P/N AD50991 with grease P/N MIL-G-23877 or equivalent.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 25 hours time in service after the effective date of this AD
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 36 with flap screw jacks 2 and 3, part numbers 24020-11, -111, -115 or 24040-11, -111, -115, and lock nuts part number MS9952-08.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Flap Screw Jacks
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_81-03-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-03-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Flap Screw Jacks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/21/1982 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| DHC-7-100 | DHC-7-101 | DHC-7-102 | DHC-7-103 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 81-03-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4513 AD NUMBER: 81-03-51 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective December 21, 1982 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-03-51 DEHAVILLAND: Amendment 39-4513. Applies to model DHC-7 airplanes serial numbers 3 through 36 certificated in all categories that have flap screw jacks 2 and 3, left and right hand, part numbers 24020-11, -111, -or -115; or 24040-11, -111, or -115 and are fitted with lock nuts, part number MS9952-08. To prevent possible damage to the flap system due to the disengagement of the lock nut, accomplish the following within the next 25 hours time in service after the effective date of this AD, unless already accomplished. 1. Inspect the flap screw jack tracks 2 and 3, Menasco part numbers 24020-11, -111 or -115 and 24040-11, -111 or -115 for correct locking feature of lock washer against the dome nut. To ensure the nuts are correctly installed, ensure that the cup lock washer P/N MS9952-08 has been tapped into groove of the lock nut P/N 24156-1 (Typical 6 places). 2. Lubricate the aft end bearing (P/N AD50991) lightly with grease P/N MIL-G- 23877 or equivalent. 3. 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. 4. 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. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). This amendment becomes effective December 21, 1982, and was effective earlier to those recipients of telegraphic AD T81-03-51, dated January 23, 1981. FOOTER:
Document Text
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AD Final Rules - DRS_81-03-51.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 81-03-51 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes Subject: Flap Screw Jacks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/21/1982 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: 81-03-51 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-4513 AD NUMBER: 81-03-51 SUBJECT HEADING: Airworthiness Directives; DeHavilland Model DHC-7 Airplanes ACTION: SUMMARY: DATES: Effective December 21, 1982 ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 81-03-51 DEHAVILLAND: Amendment 39-4513. Applies to model DHC-7 airplanes serial numbers 3 through 36 certificated in all categories that have flap screw jacks 2 and 3, left and right hand, part numbers 24020-11, -111, -or -115; or 24040-11, -111, or -115 and are fitted with lock nuts, part number MS9952-08. To prevent possible damage to the flap system due to the disengagement of the lock nut, accomplish the following within the next 25 hours time in service after the effective date of this AD, unless already accomplished. 1. Inspect the flap screw jack tracks 2 and 3, Menasco part numbers 24020-11, -111 or -115 and 24040-11, -111 or -115 for correct locking feature of lock washer against the dome nut. To ensure the nuts are correctly installed, ensure that the cup lock washer P/N MS9952-08 has been tapped into groove of the lock nut P/N 24156-1 (Typical 6 places). 2. Lubricate the aft end bearing (P/N AD50991) lightly with grease P/N MIL-G- 23877 or equivalent. 3. 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. 4. 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. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). This amendment becomes effective December 21, 1982, and was effective earlier to those recipients of telegraphic AD T81-03-51, dated January 23, 1981. FOOTER:
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