# STC SH539NW

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Onboard Weighing Systems, United States
- Description: Installation of weighing system.
- Applied: September 29, 1977
- Status date: November 23, 1977
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS 4H11](https://openairdocs.org/tcds/4H11)
- Certificate PDF: https://openairdocs.org/files/sha256/3b/54/3b54bc629e093bb608a006903f69de592a2b88f520af89c73e3a76d956ac73a5
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E8CA4CA40CA2DEF186257A4700563E8D.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SH539NW

## ADs that name it (0)

None.

## Approved models (1)

- Siam Hiller Holdings Inc. UH-12E ([TCDS 4H11](https://openairdocs.org/tcds/4H11))

## 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: SH539NW This certificate issued to: Onboard Weighing System Purt 6 of the CIViI Air Regulations:

Original Product - Type bertificate Number: 4H111 Make: Hiller Model: UH12E and 12E-4 Series Description of Type Design Change: Installation of Onboard Weighing System in accordanco with Onboard Weighing System Installation Instructions dated March 5, 1977, and Drawing List #1016 Assembly.

Limitations and Conditions: Approval of this change in type design applies basically. to the above helicopter only. This approval should not be extended to other helicopters of this model 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, including changes in type design, will introduce no adverse effect upon the airworthiness of that helicopter. A copy of this Certificate, Onboard Weighing System Installation Instructions dated 4/5/77 and Drawing List #1016 sis one felta he sapposing da the pendent seeds at tal meninin effect unlil surrendered, suspended, revcked, or a termination date is sherwise established by the Administrater of the Federal Aviation Administration Tale rf applicalion: September 29, 1977 Date Reissued:

Date of Issuance: November 23, 1977 Date Amended:

FEDERAL AVIATION By Direction of the Administrator .К. Кидд TOMINISTRATO N Acting Chief, Engineering and Manufacturing Branch (Title)

## Every issue (1)

- November 23, 1977: Issued, Current. [certificate](https://openairdocs.org/files/sha256/3b/54/3b54bc629e093bb608a006903f69de592a2b88f520af89c73e3a76d956ac73a5)

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