# STC SH5685NM

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Columbia Helicopters Inc, United States
- Description: Installation of an improved N2 Control System in accordance with Columbia Helicopters, Inc. (CHI) Master Drawing List 93-AVI-0304, Revision H, dated August 12, 2011, or later FAA-approved revision.
- Applied: May 23, 1981
- Status date: October 7, 2011
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21, Part 29
- Data sheets: [TCDS H9EA](https://openairdocs.org/tcds/H9EA)
- Certificate PDF: https://openairdocs.org/files/sha256/fe/da/feda7f44b545db633c29901a36a38838591749682bd68b49d3af449dea45a222
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/7FF5D383D976578C8625792D004CBA7D.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SH5685NM

## ADs that name it (0)

None.

## Approved models (1)

- Columbia Helicopters Inc. 234 ([TCDS H9EA](https://openairdocs.org/tcds/H9EA))

## 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.

Number SH5685NM

This certificate, issued to: Columbia Helicopters, Inc.

P.O. Box 3500 Portland, OR 97208

Part 29 of the Federal Aviation Regulations.

Original ProductType Certificate Number: H9EA Make: Columbia Helicopters, Inc.

Model: Model 234

Description of the Type Design Change: Installation of an improved N2 Control System in accordance with Columbia Helicopters, Inc. (CHI) Master Drawing List 93-AVI-0304, Revision H, dated August 12, 2011, or later FAA-approved revision.

Limitations and Conditions: Approval of this change in type design applies to the rotorcraft listed above only. This approval should not be extended to other rotorcraft of this model on which other previously approved modifications are incorporated unless it is determined by the installer that the relationship between this change and any of the other previously approved modifications, including changes in type design, will introduce no adverse effect upon the airworthiness of that rotorcraft.

The modified rotorcraft must be operated in accordance with CHI Rotorcraft Flight Manual Supplement No.

3, dated February 27, 1992, or later FAA-approved revision. This modification must be maintained in accordance with CHI Maintenance Manual Supplement C34-2/76-11-00, Revision 0, dated July 8, 2011 or later FAA-accepted revision.

A copy of this certificate, the flight manual supplement, and the maintenance manual supplement must be maintained as part of the permanent record of the modified rotorcraft. If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

Date of application: May 23, 1991 Date reissued: October 6, 1993; July 19, 2011 Date of issuance: February 27, 1992 Date amended: October 15, 1992; April 9, 1993;

October 7, 2011

(Signature) _Acting Manager, Seattle Aircraft Certification Office (Title)

## Every issue (2)

- October 7, 2011: Amended, Current. [certificate](https://openairdocs.org/files/sha256/fe/da/feda7f44b545db633c29901a36a38838591749682bd68b49d3af449dea45a222)
- July 19, 2011: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/40/f9/40f967aceb79c1263449b43624346e83498f5306ff663970202167a2ef8b452d)

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