# STC SA04392CH

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Aerometal International Inc, United States
- Description: Installation of dual Hartzell combustion heaters, P/N CD14193-1, in accordance with N18121 Installation Instructions, Revision New, dated May 28, 2019 or later FAA approved revision, into Boeing DC3A S/N 1997.
- Applied: October 2, 2018
- Status date: May 20, 2019
- Product: Aircraft
- Certification basis: Part 21
- Data sheets: [TCDS A-669](https://openairdocs.org/tcds/A-669)
- Certificate PDF: https://openairdocs.org/files/sha256/09/33/09330f432d1c12d911a93608ac469afe022a4bd5b7568879b0997d9ad551f846
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B4383C6B9AB4B5B08625843B005F9F5B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA04392CH

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company DC3A-S1CG ([TCDS A-669](https://openairdocs.org/tcds/A-669))

## 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.

Original Product--Type Certificate Number: A-669 Make: Boeing Model: DC3A Description of Type Design Change:

Installation of dual Hartzell combustion heaters, P/N CD14193-1, in accordance with N18121 Installation Instructions, Revision New, dated May 28, 2019 or later FAA approved revision, into Boeing DC3A S/N 1997.

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

2. FAA accepted Instructions for Continued Airworthiness, ICA N18121, Revision A, dated January 21, 2019 or later FAA approved revision is required.

3. FAA approved Airplane Flight Manual Supplement, AFMS N18121, Revision R1, dated May 14, 2019 or later FAA approved revision is required.

4. A copy of this certificate must be maintained as part of the permanent records for Boeing DC3A S/N 1997.

5. You cannot use descriptive data about this design change to duplicate other products. This approval is limited to only the installation made in Boeing DC3A, serial number 1997. This STC does not permit manufacturing of parts for multiple installations.

Aerometal International Inc.

22253 Yellow Gate Ln NE, Aurora, OR 97002 Date of application : October 02, 2018

Date of issuance : May 20, 2019 Date reissued :

(Signature) Roy E. Boffo Manager, Propulsion and Program Management Section Chicago Aircraft Certification Office

(Title)

## Every issue (1)

- May 20, 2019: Issued, Current. [certificate](https://openairdocs.org/files/sha256/09/33/09330f432d1c12d911a93608ac469afe022a4bd5b7568879b0997d9ad551f846)

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