AD 47-21-15
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Sky Enterprises, Inc. | RC-3 | Airworthiness Directives; Republic Model RC-3 Aircraft |
Unsafe Condition
The radio filter's condenser may be insufficiently secured, leading to a short circuit risk due to improper installation or inadequate fastening methods.
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Required Actions
Inspect the radio filter mounted on the left-hand rear engine baffle. Rework or replace filters in steel boxes (4x2 inches) if the condenser is glued in place without a 1 1/8-inch clamp or if the coil is not bolted to the box. Install a 1 1/8-inch clamp for glued condensers or replace with Republic P/N SK-17-83053-1 if the coil isn't bolted to the box.
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Compliance Time
as soon as possible, but not later than July 1, 1947
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Affected Aircraft
Sky Enterprises, Inc. Model RC-3 Aircraft, serial numbers 488 to 602 inclusive.
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Federal Register Abstract
Radio Filters
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_47-21-15.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-15 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Radio Filters 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Date: Make: Sky Enterprises, Inc. Model: RC-3 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 47-21-15 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-15 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-15 REPUBLIC: (Was Mandatory Note 5 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 488 to 602, Inclusive. Compliance required as soon as possible, but not later than July 1, 1947. Inspect the radio filter mounted on left-hand rear engine baffle. Filters in steel boxes 4 inches by 2 inches should be further inspected and reworked or replaced as described below, in order to minimize the possibility of a short circuit. Those filters which are in a smaller box need not be reworked. 1. If the coil is bolted to the box and the condenser is fastened in place with a clamp, the filter is satisfactory. If the coil is bolted to the box but the condenser is glued in place, the filter may be used provided a 1 1/8-inch diameter clamp is added to fasten the condenser in place. 2. Filters in which the coil is not bolted to the box should be replaced by a new filter assembly, Republic P/N SK-17-83053-1. (Republic RC-3 Seabee Service Bulletin No. 15 dated April 8, 1947, covers this same subject.) FOOTER:
Document Text
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AD Final Rules - DRS_47-21-15.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 47-21-15 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Republic Model RC-3 Aircraft Subject: Radio Filters 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: 47-21-15 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 47-21-15 SUBJECT HEADING: Airworthiness Directives; Republic Model RC-3 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 47-21-15 REPUBLIC: (Was Mandatory Note 5 of AD-769-2.) Applies to Model RC-3 Aircraft Serial Numbers 488 to 602, Inclusive. Compliance required as soon as possible, but not later than July 1, 1947. Inspect the radio filter mounted on left-hand rear engine baffle. Filters in steel boxes 4 inches by 2 inches should be further inspected and reworked or replaced as described below, in order to minimize the possibility of a short circuit. Those filters which are in a smaller box need not be reworked. 1. If the coil is bolted to the box and the condenser is fastened in place with a clamp, the filter is satisfactory. If the coil is bolted to the box but the condenser is glued in place, the filter may be used provided a 1 1/8-inch diameter clamp is added to fasten the condenser in place. 2. Filters in which the coil is not bolted to the box should be replaced by a new filter assembly, Republic P/N SK-17-83053-1. (Republic RC-3 Seabee Service Bulletin No. 15 dated April 8, 1947, covers this same subject.) FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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