# STC SR01180LA

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Diamond Upgrades, LLC, United States
- Description: Installation of Pratt & Whitney PT6T-3DF Twin-Pack in place of PT6T-3B, -3BE, -3BF, -3BG Twin Pack
- Applied: April 22, 2001
- Status date: October 11, 2012
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21, Part 29
- Data sheets: [TCDS H4SW](https://openairdocs.org/tcds/H4SW)
- Certificate PDF: https://openairdocs.org/files/sha256/e4/4f/e44f9e5be04cd5ba3aa6a06fac1360631eecd9c6c1147aef3c17aec62892942a
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B3AF936C06EF3CBA86257A9500482DB2.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SR01180LA

## ADs that name it (0)

None.

## Approved models (1)

- Bell Helicopter Textron 412 ([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.

This Certificate issued to DIAMOND UPGRADES, LLC 920 KING STREET 2ND FLOOR WILMINGTON, DE 19801 Part 29* of the Federal Aviation Regulations. *Certification basis is set forth in Type Certificate Data Sheet H4SW Original Product Type Certificate Number :

H4SW Bell 412 Description of Type Design Change : Installation of Pratt & Whitney PT6T-3DF Twin-Pack in place of PT6T-3B, -3BE, -3BF, -3BG Twin P ack, in accordance with Airlane U pgrades’ Installation Instruction AU-412010420, Revision N/C, dated April 20, 2001, or later FAA approved revision. FAA Approved Rotorcraft Flight Manual Supplement No. AU-412010423, dated June 28, 2001, or later FAA approved revision is required with this installation.

Limitations and Conditions : The installation should not be incorporated in any aircraft unless it is determined that the interrelationship between this in stallation and any previous ly approved configuration will not introduce any adverse effect upon the airwor thiness of the aircraft. The approval of this modification applies to the above-noted rotorcraft model series only and the incorporation of Bell Helicopter Technical Bulletin 412-84-44, 412-90- 84, 412-93-118, 412-99-152, and 412-99-165. (See page 3). A copy of this STC must be included in th e permanent records of the modified aircraft. If the holder agrees to permit another person to use this certif icate to alter the product, the holder shall give the other person written evidence of that permission.

Date of application : April 22, 2001

Date of issuance : June 28, 2001

Date reissued : October 11, 2012

Date amended : January 22, 2003, March 12, 2004

( Signature) Manager, Propulsion Branch Los Angeles Aircraft Certification Office ( Title)

NOTE:

**DO NOT DELETE THIS PAGE.**

**DO NOT ADD ANY DATA TO THIS PAGE.**

**THIS PAGE IS FOR PAGE NUMBERING PURPOSES, PLEASE DISCARD PRINTED COPY.**

Number SR01180LA

Limitations and Conditions (Continued): The limitation for the installed PT6T-3DF engine are: 1) the same performance and operating limits as the previously installed PT6T-3B, -3BE, -3BF, -3BG; and 2) the increased OEI performance of the PT6T-3DF with the appropriate engine instruments and marking installed.

--END--

## Every issue (2)

- October 11, 2012: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/e4/4f/e44f9e5be04cd5ba3aa6a06fac1360631eecd9c6c1147aef3c17aec62892942a)
- March 12, 2004: Amended, Historical. [certificate](https://openairdocs.org/files/sha256/ad/2f/ad2ff7c2dd4ebb31b71afb99e06ab714addd910b8a55a02662f407c0ac921669)

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