# STC SH431NW

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Simplex Manufacturing Co, United States
- Description: Installation of Simplex Manufacturing Company Model 500 spray system.
- Applied: October 7, 1975
- Status date: April 29, 1983
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS H3WE](https://openairdocs.org/tcds/H3WE)
- Certificate PDF: https://openairdocs.org/files/sha256/90/6c/906cfa9743b26183467450d7052b6b5694e85d2eb0edad2bf6948214f4f8e293
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F162624E49DF632386257A46006DBC6D.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SH431NW

## ADs that name it (0)

None.

## Approved models (2)

- MD Helicopter Inc. 369D ([TCDS H3WE](https://openairdocs.org/tcds/H3WE))
- MD Helicopter Inc. 369H ([TCDS H3WE](https://openairdocs.org/tcds/H3WE))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number S1431N6 This certificate issued to: Simplex Manufacturing Company Part 6 of the CIVI1 Air Regulations: › dated December 20, 1956.

Original Product -Type Certificate Number: H3WE Make: Hughes Model: 369D and H Series Description of Type Design Change: Installation of Simplex Manufacturing Company Model 5000 spray system in accordance with Simplex Manutacturing Company Drawing List No. 5030.

Limitations and Conditions: Approval of this change in type design applies basically to the above models of helicopters only. This approval should not be extended to other helicopters of these models on which other previously approved modifications are incorporated unless it is determined that the interrelationship between this change and any of those other previously approved modifications will introduce no adverse effect upon the airworthiness of that helicopter. A copy of this Certificate, Simplex FAA Approved Airplane Flight Manual Supplement, and Simplex Drawing List No. 5030 shall be maintained as part of the permanent records for the modified helicopter.

Date of Application: October 1, 1975 Date Reissued:

Date of Issuance: March 26, 1977 Date Amended: May 9, 1977; April 10, 1978;

FEDERAL AVTATION Charles C tehroede April 29, 1983 ( Signature ) TO MINISTRATIO Acting Manager, Seattle Aircraft Certification Office, ANM-100S (Title)

47.

## Every issue (1)

- April 29, 1983: Amended, Current. [certificate](https://openairdocs.org/files/sha256/90/6c/906cfa9743b26183467450d7052b6b5694e85d2eb0edad2bf6948214f4f8e293)

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