AD 47-21-23
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sky Enterprises, Inc. | RC-3 | Airworthiness Directives; Republic Model RC-3 Aircraft |
Unsafe Condition
Loosening of engine cooling fan capscrews and tab locks could lead to fan and pulley sheave detachment, resulting in engine cooling system failure.
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Required Actions
Inspect engine cooling fan capscrews for tightness and tab locks for in-place condition. Replace capscrews with P/N 17778 drilled head capscrews, install plain washers, torque to 20 foot-pounds, and safety with 0.041-inch stainless steel wire. Reinspect after 5 hours of operation and reassemble properly each time the fan is removed.
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Compliance Time
before the next flight and after 5 hours of operation following each installation of fan
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Affected Aircraft
Republic Model RC-3 Aircraft with Engine Serial Numbers 23001 to 24083, Inclusive.
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Federal Register Abstract
Engine Cooling Fan
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-21-23.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-23 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Engine Cooling Fan 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Date: Make: Sky Enterprises, Inc. Model: RC-3 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-21-23 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-23 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-23 REPUBLIC: (Was Service Note 3 of AD-769-2.) Applies to Model RC-3 Aircraft with Engine Serial Numbers 23001 to 24083, Inclusive. Compliance required before the next flight and after 5 hours of operation following each installation of fan. Inspect the engine cooling fan capscrews for tightness. If tab locks are installed ascertain whether the locks are still in place. If the capscrews or the locks have loosened remove the capscrews, fan and pulley sheave. Clean and inspect parts for wear. Reassemble carefully using P/N 17778 drilled head capscrews with plain washers. Torque to 20 foot-pounds, operate engine up to 1,500 r.p.m. for 5 minutes, retorque and safety with 0.041-inch stainless steel wire. Visually inspect locking wire and capscrews after 5 hours of operation. Reassemble in this manner every time the fan is removed. Obtain the new capscrews, washers, and wire from your Seabee distributor or the engine manufacturer. (Franklin Service Bulletin No. 57 dated June 9, 1947, which supersedes Bulletin No. 50 covers this same subject.) FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_47-21-23.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-23 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Engine Cooling Fan 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: 47-21-23 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-23 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-23 REPUBLIC: (Was Service Note 3 of AD-769-2.) Applies to Model RC-3 Aircraft with Engine Serial Numbers 23001 to 24083, Inclusive. Compliance required before the next flight and after 5 hours of operation following each installation of fan. Inspect the engine cooling fan capscrews for tightness. If tab locks are installed ascertain whether the locks are still in place. If the capscrews or the locks have loosened remove the capscrews, fan and pulley sheave. Clean and inspect parts for wear. Reassemble carefully using P/N 17778 drilled head capscrews with plain washers. Torque to 20 foot-pounds, operate engine up to 1,500 r.p.m. for 5 minutes, retorque and safety with 0.041-inch stainless steel wire. Visually inspect locking wire and capscrews after 5 hours of operation. Reassemble in this manner every time the fan is removed. Obtain the new capscrews, washers, and wire from your Seabee distributor or the engine manufacturer. (Franklin Service Bulletin No. 57 dated June 9, 1947, which supersedes Bulletin No. 50 covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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