AD 79-14-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Viking Air Limited | DHC-6-1 | Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft |
| aircraft | Viking Air Limited | DHC-6-100 | Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft |
| aircraft | Viking Air Limited | DHC-6-200 | Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft |
| aircraft | Viking Air Limited | DHC-6-300 | Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft |
Unsafe Condition
Loss of elevator control and improper operation of the elevator control system due to incorrect torque on four bolts on the aft elevator cable control quadrant.
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Required Actions
Inspect and torque-correct four bolts on the aft elevator cable control quadrant within 100 hours in service. Perform Modification No. 6/1679 within 600 hours in service. Use approved equivalent methods if available.
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Compliance Time
Within the next 100 hours in service after the effective date of this airworthiness directive and within 600 hours in service after the effective date.
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Affected Aircraft
de Havilland Aircraft of Canada, Limited Model DHC-6 Series Twin Otter Aircraft, serial numbers 331 through 563 inclusive, 565 through 587 inclusive, 589 through 598 inclusive, 600, 601, 603, and 604.
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Federal Register Abstract
Elevator Control System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_79-14-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-14-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/06/1979 Make: Viking Air Limited Model: DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 79-14-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3509 AD NUMBER: 79-14-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft ACTION: SUMMARY: DATES: Effective July 6, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-14-01 De HAVILLAND: Amendment 39-3509. Applies to DeHavilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft, certificated in all categories, S/N 331 through 563 inclusive, 565 through 587 inclusive, 589 through 598 inclusive, 600, 601, 603 and 604. Compliance is required as indicated. To preclude loss of elevator control and ensure proper operation of the elevator control system: (a) Within the next 100 hours in service after the effective date of this airworthiness directive, unless previously accomplished, inspect the four bolts on the aft elevator cable control quadrant for correct torque and alter, as necessary, in accordance with the INSPECTION and RECTIFICATION paragraphs of ACCOMPLISHMENT INSTRUCTIONS in DeHavilland S/B No. 6/379 dated December 11, 1978, or an approved equivalent. (b) Within 600 hours in service after the effective date of this airworthiness directive, unless already accomplished, alter in accordance with Modification No. 6/1679, noted in S/B No. 6/379, or an approved equivalent. (c) Equivalent inspections, alterations and replacement parts must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (d) Upon submission of substantiating data by an owner, or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the compliance time specified in this AD. This amendment is effective July 6, 1979. FOOTER:
Document Text
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AD Final Rules - DRS_79-14-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 79-14-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft Subject: Elevator Control System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 07/06/1979 Make: Viking Air Limited Model: DHC-6-1 | DHC-6-100 | DHC-6-200 | DHC-6-300 Product Type: Aircraft Product Subtype: Small 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: 79-14-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3509 AD NUMBER: 79-14-01 SUBJECT HEADING: Airworthiness Directives; de Havilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft ACTION: SUMMARY: DATES: Effective July 6, 1979. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 79-14-01 De HAVILLAND: Amendment 39-3509. Applies to DeHavilland Aircraft of Canada, Limited, Model DHC-6 Series Twin Otter Aircraft, certificated in all categories, S/N 331 through 563 inclusive, 565 through 587 inclusive, 589 through 598 inclusive, 600, 601, 603 and 604. Compliance is required as indicated. To preclude loss of elevator control and ensure proper operation of the elevator control system: (a) Within the next 100 hours in service after the effective date of this airworthiness directive, unless previously accomplished, inspect the four bolts on the aft elevator cable control quadrant for correct torque and alter, as necessary, in accordance with the INSPECTION and RECTIFICATION paragraphs of ACCOMPLISHMENT INSTRUCTIONS in DeHavilland S/B No. 6/379 dated December 11, 1978, or an approved equivalent. (b) Within 600 hours in service after the effective date of this airworthiness directive, unless already accomplished, alter in accordance with Modification No. 6/1679, noted in S/B No. 6/379, or an approved equivalent. (c) Equivalent inspections, alterations and replacement parts must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. (d) Upon submission of substantiating data by an owner, or operator through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region, may adjust the compliance time specified in this AD. This amendment is effective July 6, 1979. FOOTER:
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