# STC SH17NW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Onboard Systems International, United States
- Description: Installation of Chadwick Electronic weighing system C-47.
- Applied: June 30, 1972
- Status date: April 28, 1987
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS H4SW](https://openairdocs.org/tcds/H4SW)
- Certificate PDF: https://openairdocs.org/files/sha256/f6/67/f667ae98f66355743bbcb885bc5db3d082daee7d70504d9166e0940cc4492473
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2C4949CB4A5AF0BF86257AD400636F73.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SH17NW

## ADs that name it (1)

- [AD 78-21-02](https://openairdocs.org/ad/78-21-02): External Load Link Assembly · Chadwick electronic weighing system C47 (Onboard Systems STC SH149WE or SH17NW). Effective Oct 12, 1978. Named in the applicability

## Approved models (2)

- Bell Helicopter Textron Inc. 212 ([TCDS H4SW](https://openairdocs.org/tcds/H4SW))
- Bell Helicopter Textron Inc. 412 ([TCDS H4SW](https://openairdocs.org/tcds/H4SW))

## 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 SHITNW This certificate issued to: Onboard Systems Certifies that the change in the type design for the fellowing product with the limitations and conditions Federal Aviatior Regulations •903(c), •1323, & .1505(b) of Amdt. 29-3 & Special Condition dated August 29, 1969 and FAA SW-210 letter dated February 3, 1971.

Original Product - Type Certificate Number: H45W Make: Be11 Model: 212 and 412 Deserplion sype Design thange: Installation of Chadwick Electronic Weighing System C-47 in accordance with the drawings listed on FAA Sealed Chadwick Incorporated Drawing List 47-10800-1 or 47-10800-3.

This modification is applicable to only Helicopters with sling installations in accordance with Bell Service Limitations and Conditions: Instructions No. 212-5; FAA Approved Chadwick Rotorcraft Flight Manual Supplement 47-10500-003 is required. A copy of this certificate shall be maintained as part of the permanent records of each Helicopter so modified. This approval should not be extended to other specific helicopters of these same 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 the February 16, 1973 Date Amended: November 4, 1982; March 15, 1984 FEDERAL AVIATION By Direction of the Administrator TAMIN STRATOS Manager, Seattle Aircraft Asst. 2 Кицера (Signature ), Certification Office, ANM-100S (Title)

FAA FoR 8110-2 (10-68)

## Every issue (1)

- April 28, 1987: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/f6/67/f667ae98f66355743bbcb885bc5db3d082daee7d70504d9166e0940cc4492473)

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