# STC SR12148LA

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Extex Engineered Products, United States
- Description: Installation of modified configurations of the Bell Helicopter Textron (BHT) Model 412 “Arm and Bearing Assembly”
- Applied: February 28, 2024
- Status date: November 21, 2025
- Product: Aircraft, Rotorcraft
- Certification basis: Part 29
- Data sheets: [TCDS H4SW](https://openairdocs.org/tcds/H4SW)
- Certificate PDF: https://openairdocs.org/files/sha256/a0/37/a0372628a4ab2f2ee6fb971d5aa20a319fe5cf1d9ecaa2d48aa8c37e1282197e
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID141260209220251125201900.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SR12148LA

## ADs that name it (0)

None.

## Approved models (2)

- Bell Helicopter Textron Inc. 412 ([TCDS H4SW](https://openairdocs.org/tcds/H4SW))
- Bell Helicopter Textron Inc. 412EP ([TCDS H4SW](https://openairdocs.org/tcds/H4SW))

## What the certificate says

Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record.

Number   This certificate issued to:

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Original Product 7\SH&HUWLILFDWH1XPEHU Make:

VHHFRQWLQXDWLRQVKHHW IRUDGGLWLRQDOGDWHV By Direction of the Administrator Signature:

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412, 412EP Approval of this change in type design applies to the listed aircraft models. The installer must determine whether this design change is compatible with previously approved modifications. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission.(Continued on Page 3) 02/28/2024 11/21/2025 for Gregory S. DiLibero Manager, West Certification Branch 3 Installation of modified configurations of the Bell Helicopter Textron (BHT) Model 412 “Arm and Bearing Assembly” in accordance with FAA Approved Extex drawing 4E2-010-100 Revision IR, dated November 13, 2025, or later FAA approved revision.

See continuation sheet 3 for the certification basis.

Number   (IIHFWLYH'DWH I Transferr Endorsementt Transfer the ownership of Supplemental Type Certificate Number:

Too (Name and address of transferee):

Date oI transfer:

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United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate  (Continuation Sheet) Number  (IIHFWLYH'DWH  $Q\DOWHUDWLRQRIWKLVFHUWLILFDWHLVSXQLVKDEOH E\D ILQH RIQRW H[FHHGLQJRULPSULVRQPHQWQRWH[FHHGLQJ \HDUVRUERWK7KLVFHUWLILFDWH PD\ EHWUDQVIHUUHGRUPDGH DYDLODEOHWR WKLUGSHUVRQVE\OLFHQVLQJDJ UHHPHQWVLQDFFRUGDQFHZLWK&)53RVVHVVLRQ RIWKLV6XSSOHPHQWDO7\SH &HUWLILFDWH 67& GRFXPHQWE\SHUVRQVRWKHUWKDQ WKH 67&KROGHUGR HVQRWFRQVWLWXWHULJKWVWRWKHGHVLJQGDWD QRUWRDOWHUDQ DLUFU DIW DLUFUDIWHQJLQH KROGHU$Q 67&KROGHUZKRDOORZVDSHUVRQWRXVHWKH67&WRDOWHUDQDLUFUDIWDLUFUDIWHQJLQHRUSURSHOOHUPXVWSURYLGH WKDWSHUVRQZLWKZULWWHQ SHUPLVVLRQ DFFHSWDEOHWR WKH)$$ 5HI &)5  )$$  3DJH BBBRI BBB SR12148LA Limitations and Conditions(Continued):

Instructions for Continued Airworthiness report T-719 Revision IR, or other FAA accepted ICA must be made available at the time of installation.

Certification Basis:

Certification Basis set forth in Type Certificate Data Sheet H4SW 33

## Every issue (1)

- November 21, 2025: Issued, Current. [certificate](https://openairdocs.org/files/sha256/a0/37/a0372628a4ab2f2ee6fb971d5aa20a319fe5cf1d9ecaa2d48aa8c37e1282197e)

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