AD 47-21-21
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sky Enterprises, Inc. | RC-3 | Airworthiness Directives; Republic Model RC-3 Aircraft |
Unsafe Condition
Cracks in the slots at the upper end of each tip float strut (P/N 17W23001) could lead to strut failure.
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Required Actions
Inspect the two slots at the upper end of each tip float strut for cracks immediately and periodically at 50-hour intervals. Replace any strut with cracks prior to further operation. Ensure struts without relief holes at the ends of slots are inspected every 50 hours.
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Compliance Time
Immediately
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Affected Aircraft
Republic Model RC-3 Aircraft, serial numbers 5 to 236 inclusive, equipped with tip float struts (P/N 17W23001)
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Federal Register Abstract
Tip Float Struts
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-21-21.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-21 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Tip Float Struts 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Date: Make: Sky Enterprises, Inc. Model: RC-3 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-21-21 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-21 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-21 REPUBLIC: (Was Service Note 1 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 5 to 236, Inclusive. Inspection required immediately and periodically as noted below. Inspect two slots at upper end of each tip float strut (P/N 17W23001) very carefully for cracks. Slots are located inside of wing contour, therefore, struts must be removed from wing at upper attachment for proper inspection. If any cracks are present, strut shall be replaced prior to further operation. All struts without relief holes at ends of slots as recommended by manufacturer shall be inspected for cracks at 50-hour intervals. (Republic Seabee Service Bulletin No. 12 covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_47-21-21.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-21 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Tip Float Struts 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: 47-21-21 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-21 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-21 REPUBLIC: (Was Service Note 1 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 5 to 236, Inclusive. Inspection required immediately and periodically as noted below. Inspect two slots at upper end of each tip float strut (P/N 17W23001) very carefully for cracks. Slots are located inside of wing contour, therefore, struts must be removed from wing at upper attachment for proper inspection. If any cracks are present, strut shall be replaced prior to further operation. All struts without relief holes at ends of slots as recommended by manufacturer shall be inspected for cracks at 50-hour intervals. (Republic Seabee Service Bulletin No. 12 covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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