AD 66-13-03
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Maryland Air Industries, Inc. | F-27 | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27A | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27B | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27F | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27G | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27J | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
| aircraft | Maryland Air Industries, Inc. | F-27M | Airworthiness Directives; Fairchild Model F-27 Series Airplanes |
Unsafe Condition
Failure of both inverters and resulting loss of essential load circuits due to a failure of a common ground.
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Required Actions
Modify the inverter ground circuit in accordance with Fairchild Service Bulletin 34-9 (dated December 16, 1965) or an FAA-approved equivalent for airplanes with specific conforming drawings and modifications. For others, use Service Bulletins 34-4 or 34-9. Compliance may be adjusted upon FAA approval based on operator's inspection schedule.
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Compliance Time
within the next 350 hours' time in service after the effective date of this AD
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Affected Aircraft
Maryland Air Industries, Inc. Model F-27 Series Airplanes (F-27, F-27A, F-27B, F-27F, F-27G, F-27J, F-27M)
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Federal Register Abstract
Inverter Ground System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-13-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-13-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Model F-27 Series Airplanes Subject: Inverter Ground System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/11/1966 Make: Maryland Air Industries, Inc. Model: F-27 | F-27A | F-27B | F-27F | F-27G | F-27J | F-27M 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: 66-13-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-232 AD NUMBER: 66-13-03 SUBJECT HEADING: Airworthiness Directives; Fairchild Model F-27 Series Airplanes ACTION: SUMMARY: DATES: Effective June 11, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-13-03 FAIRCHILD: Amdt. 39-232 Part 39 Federal Register May 12, 1966. Applies to Model F-27 Series Airplanes. Compliance required within the next 350 hours' time in service after the effective date of this AD, unless already accomplished. To prevent failure of both inverters and resulting loss of essential load circuits due to a failure of a common ground, accomplish the following: (a) For airplanes with inverter ground circuits conforming to Fairchild Drawing 27-740027 including EAI No. 1, or that have been modified in accordance with Fairchild Service Bulletin No. 34-4, dated November 5, 1959, modify the inverter ground circuit in accordance with the "Accomplishment Instructions" of Fairchild Service Bulletin 34-9, dated December 16, 1965, or later FAA-approved revision, or an FAA-approved equivalent. (b) For airplanes with inverter ground circuits conforming to Fairchild Drawing 27-740027 not including EAI No. 1, and that have not been modified in accordance with Fairchild Service Bulletin No. 34-4, dated November 5, 1959, modify the inverter ground circuit in accordance with Fairchild Service Bulletins 34-4, dated November 5, 1959, or 34-9, dated December 16, 1965, or later FAA-approved revisions, or an FAA-approved equivalent. (c) Upon request of the operator an FAA maintenance inspector, subject to the prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region may adjust the compliance time specified in this AD to permit compliance at an established inspection period of the operator, if the request contains substantiating data to justify the increase for that operator. This directive effective June 11, 1966. FOOTER:
Document Text
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AD Final Rules - DRS_66-13-03.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-13-03 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Fairchild Model F-27 Series Airplanes Subject: Inverter Ground System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/11/1966 Make: Maryland Air Industries, Inc. Model: F-27 | F-27A | F-27B | F-27F | F-27G | F-27J | F-27M 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: 66-13-03 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-232 AD NUMBER: 66-13-03 SUBJECT HEADING: Airworthiness Directives; Fairchild Model F-27 Series Airplanes ACTION: SUMMARY: DATES: Effective June 11, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-13-03 FAIRCHILD: Amdt. 39-232 Part 39 Federal Register May 12, 1966. Applies to Model F-27 Series Airplanes. Compliance required within the next 350 hours' time in service after the effective date of this AD, unless already accomplished. To prevent failure of both inverters and resulting loss of essential load circuits due to a failure of a common ground, accomplish the following: (a) For airplanes with inverter ground circuits conforming to Fairchild Drawing 27-740027 including EAI No. 1, or that have been modified in accordance with Fairchild Service Bulletin No. 34-4, dated November 5, 1959, modify the inverter ground circuit in accordance with the "Accomplishment Instructions" of Fairchild Service Bulletin 34-9, dated December 16, 1965, or later FAA-approved revision, or an FAA-approved equivalent. (b) For airplanes with inverter ground circuits conforming to Fairchild Drawing 27-740027 not including EAI No. 1, and that have not been modified in accordance with Fairchild Service Bulletin No. 34-4, dated November 5, 1959, modify the inverter ground circuit in accordance with Fairchild Service Bulletins 34-4, dated November 5, 1959, or 34-9, dated December 16, 1965, or later FAA-approved revisions, or an FAA-approved equivalent. (c) Upon request of the operator an FAA maintenance inspector, subject to the prior approval of the Chief, Engineering and Manufacturing Branch, FAA Eastern Region may adjust the compliance time specified in this AD to permit compliance at an established inspection period of the operator, if the request contains substantiating data to justify the increase for that operator. This directive effective June 11, 1966. FOOTER:
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