AD 47-21-20
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sky Enterprises, Inc. | RC-3 | Airworthiness Directives; Republic Model RC-3 Aircraft |
Unsafe Condition
Excessive loss of oil through oil pressure gage line in case of its failure.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install a restrictor fitting at the engine end of the oil pressure gage line.
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Compliance Time
not later than the next 25 hours of operation subsequent to July 1, 1947, and in any case not later than September 1, 1947
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Affected Aircraft
Republic Model RC-3 Aircraft Serial Numbers 426 Through 484, Except 446, 447, 452, 455, 460, 468, 471, 473, 475, 480, 481 and 483.
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Federal Register Abstract
Oil Pressure Gage Line Restrictor
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-21-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-20 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Oil Pressure Gage Line Restrictor Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sky Enterprises, Inc. Model: RC-3 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-21-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-20 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-20 REPUBLIC: (Was Mandatory Note 10 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 426 Through 484, Except 446, 447, 452, 455, 460, 468, 471, 473, 475, 480, 481 and 483. Compliance required not later than the next 25 hours of operation subsequent to July 1, 1947, and in any case not later than September 1, 1947. In order to prevent excessive loss of oil through oil pressure gage line in case of its failure, install a restrictor fitting at the engine end of that line. (Seabee Service Bulletin No. 13, dated March 17, 1947, covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_47-21-20.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-20 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Oil Pressure Gage Line Restrictor Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: Sky Enterprises, Inc. Model: RC-3 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: 47-21-20 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-20 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-20 REPUBLIC: (Was Mandatory Note 10 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 426 Through 484, Except 446, 447, 452, 455, 460, 468, 471, 473, 475, 480, 481 and 483. Compliance required not later than the next 25 hours of operation subsequent to July 1, 1947, and in any case not later than September 1, 1947. In order to prevent excessive loss of oil through oil pressure gage line in case of its failure, install a restrictor fitting at the engine end of that line. (Seabee Service Bulletin No. 13, dated March 17, 1947, covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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