# STC SH449NW

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Measurement Systems Intl, United States
- Description: Installation of an electronic weighing system (for monitoring cargo weight)
- Applied: April 11, 1977
- Status date: December 4, 1980
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS 1H4](https://openairdocs.org/tcds/1H4)
- Certificate PDF: https://openairdocs.org/files/sha256/c8/16/c8164d74d617ce369b3a310fb4670a5f6861f6aa9faebe3f775246666ef7a940
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/3FC1D28C352254B186257A46006E0D78.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SH449NW

## ADs that name it (0)

None.

## Approved models (1)

- Sikorsky Aircraft Corporation S-55 ([TCDS 1H4](https://openairdocs.org/tcds/1H4))

## What the certificate says

The certificate is a scan without a text layer; open the PDF to read it.

## Every issue (1)

- December 4, 1980: Amended, Current. [certificate](https://openairdocs.org/files/sha256/c8/16/c8164d74d617ce369b3a310fb4670a5f6861f6aa9faebe3f775246666ef7a940)

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