# STC SR11844CH

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Hartzell Propeller LLC, United States
- Description: Installation of Heli-Preheat Kit, p/n TA3391-1 for 115 volt application
- Applied: December 20, 2023
- Status date: August 12, 2026
- Product: Aircraft, Rotorcraft
- Certification basis: Part 27
- Data sheets: [TCDS H88EU](https://openairdocs.org/tcds/H88EU)
- Certificate PDF: https://openairdocs.org/files/sha256/07/12/071276649d7f9fbb1cb8bce931c50cef4d12c5a958bc39081e07fe69966fca34
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID112781748220260821134037.0001
- DRS record last changed: August 21, 2026
- Page: https://openairdocs.org/stc/SR11844CH

## ADs that name it (0)

None.

## Approved models (9)

- Airbus Helicopters Deutschland GmbH (AHD) EC135P1 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135P2 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135P2+ ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135P3 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135T1 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135T2 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135T2+ ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC135T3 ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))
- Airbus Helicopters Deutschland GmbH (AHD) EC635T2+ ([TCDS H88EU](https://openairdocs.org/tcds/H88EU))

## 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.

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number 

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**HARTZELL PROPELLER LLC**

ONE PROPELLER PLACE PIQUA, OHIO 45356-2634 Part 27 Title 14 of the Code of Federal Regulations Airbus Helicopters Deutschland GmbH *See continuation sheet 3 of 3 H88EU Installation of Heli-Preheat Kit, p/n TA3391-(l, 10) for 115 volt application or p/n TA3391-(2,

20) for 230 volt application in accordance with Heli-Preheat Kit drawing TA339l-( ) Revision G, dated March 26, 2026 or later FAA-approved revision, and Heli-Preheat Kit Installation Instruction TNH3391 Revision D, dated September 05, 2025 or later FAA-approved revision.

1. The installer must determine whether this design change is compatible with previously approved modifications.

2. 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.

(See Continuation Sheet 3 of 3) 12/20/23 11/25/24 8/12/26 Bo R. Landess STC ODA administrator Hartzell Propeller ODA-100082-CE 3

(Continuation Sheet) Number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ontinued from Page 1: Model)

EC135P1, EC135T1, EC135P2, EC135T2, EC135P2+, EC135T2+, EC635T2+, EC135P3, EC135T3 (Continued from Page 1: Limitations and Conditions)

3. FAA-accepted Instructions for Continued Airworthiness (ICA) document# TCA1000 Revision D, dated August 7, 2023 or later FAA approved revisions, and Operating Guide document# TPG1000 Revision F, dated August 7, 2023 or later FAA approved revision are required.

4. A copy of this certificate must be maintained as part of the permanent records for the modified rotorcraft.

---------------------------------------------------- END -------------------------------------------------------- 33 08/12/26

## Every issue (2)

- August 12, 2026: Amended, Current. [certificate](https://openairdocs.org/files/sha256/07/12/071276649d7f9fbb1cb8bce931c50cef4d12c5a958bc39081e07fe69966fca34)
- November 25, 2024: Issued, Historical. [certificate](https://openairdocs.org/files/sha256/13/a5/13a5ce5d192fe8c34c5acf3886eb2c773f55b5eeb29a39bc396a3ec712e8a964)

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