AD 47-21-22
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sky Enterprises, Inc. | RC-3 | Airworthiness Directives; Republic Model RC-3 Aircraft |
Unsafe Condition
Loosening of engine mounting bolts due to absence or improper installation of tab type lockwashers.
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Required Actions
Inspect engine mounting bolts before next flight and at each subsequent 25 hours of operation. Check torque to 25 foot-pounds for 3/8-inch bolts and 30 foot-pounds for 7/16-inch bolts. Install tab type lockwashers (AMI P/N 15175 and 15176) if loosening occurs or if not already installed.
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Compliance Time
before next flight
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Affected Aircraft
Republic Model RC-3 Aircraft as specified in Service Note 2 of AD-769-2
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Federal Register Abstract
Engine Mounting Bolt Lock Washers
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-21-22.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-22 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Engine Mounting Bolt Lock Washers 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Date: Make: Sky Enterprises, Inc. Model: RC-3 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-21-22 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-22 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-22 REPUBLIC: (Was Service Note 2 of AD-769-2.) Applies to Model RC-3 Aircraft. Inspection required before next flight and at each subsequent 25 hours of operation. If no tab type lockwashers are installed, check tightness of engine mounting bolts to torque of 25 foot-pounds on 3/8-inch bolts and 30 foot-pounds on 7/16-inch bolts. If it is found that loosening has occurred it will be necessary to install tab type lockwashers under all engine mounting bolts. (AMI P/N 15175 for 3/8-inch bolts, AMI P/N 15176 for 7/16-inch bolts.) If tab type lockwashers have been installed previously and tabs are in place, inspection is required only at the regular 100-hour periods. (Aircooled Motors Service Bulletin No. 47 pertains to this subject.) FOOTER:
Document Text
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AD Final Rules - DRS_47-21-22.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-22 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Engine Mounting Bolt Lock Washers 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: 47-21-22 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-22 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-22 REPUBLIC: (Was Service Note 2 of AD-769-2.) Applies to Model RC-3 Aircraft. Inspection required before next flight and at each subsequent 25 hours of operation. If no tab type lockwashers are installed, check tightness of engine mounting bolts to torque of 25 foot-pounds on 3/8-inch bolts and 30 foot-pounds on 7/16-inch bolts. If it is found that loosening has occurred it will be necessary to install tab type lockwashers under all engine mounting bolts. (AMI P/N 15175 for 3/8-inch bolts, AMI P/N 15176 for 7/16-inch bolts.) If tab type lockwashers have been installed previously and tabs are in place, inspection is required only at the regular 100-hour periods. (Aircooled Motors Service Bulletin No. 47 pertains to this subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
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