# AD 47-47-12: Carburetor Antiswirl Vanes

- Type: Airworthiness directive
- Status: Current
- Products: Sky Enterprises RC-3
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Registered aircraft: 126 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/51EEBD50A408829286256A5600669FC6.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/47-47-12

## The airworthiness directive

47-47-12 REPUBLIC: (Was Mandatory Note 12 of AD-769-2.) Applies to RC-3 Aircraft Serial Numbers 5 Through 1035 Inclusive Except the Following Which Have Been Modified at the Factory: 767, 915, 948, 949, 957, 959 Through 999 Inclusive, 1004 Through 1010 Inclusive, 1014, 1019 Through 1025 Inclusive. Serial 1036 and up Have Been Modified at the Factory Prior to Delivery.

Compliance required not later than December 31, 1947.

To prevent excessive drop-off in engine r.p.m. when carburetor heat is used, anti-swirl vanes, Republic P/N 17P 68014-20 must be installed in the air duct below the carburetor.

(Republic Seabee Service Bulletin No. 18 dated August 26, 1947, covers this same subject.)

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A-769](https://openairdocs.org/tcds/A-769): Sky Enterprises Inc.; names 1 of 1 models: RC-3

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 126 (126 by airframe model, 0 by engine model)
- Makers: Republic 122, Downer 2, Republic Aviation Corp USA 1, Simuflight Seattle-1-Stol 1

Models with the most aircraft:

- [Republic RC-3](https://openairdocs.org/model/republic-rc-3): 122 aircraft (airframe model)
- [Downer RC-3](https://openairdocs.org/model/downer-rc-3): 2 aircraft (airframe model)
- [Republic Aviation Corp USA SEABEE RC-3](https://openairdocs.org/model/republic-aviation-corp-usa-seabee-rc-3): 1 aircraft (airframe model)
- [Simuflight Seattle-1-Stol RC-3](https://openairdocs.org/model/simuflight-seattle-1-stol-rc-3): 1 aircraft (airframe model)

All 4 models: https://openairdocs.org/ad/47-47-12/models.md
Every aircraft: https://openairdocs.org/ad/47-47-12/aircraft.md

Its text cites no advisory circulars or STCs.

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