# STC ST09011SC

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Sierra Industries Ltd., United States
- Description: Installation of a pilot's, control wheel mounted, alternate gear horn silence switch.
- Applied: February 14, 1994
- Status date: July 14, 2017
- Product: Aircraft, Small Airplane
- Certification basis: Part 21, Part 25
- Data sheets: [TCDS A22CE](https://openairdocs.org/tcds/A22CE)
- Certificate PDF: https://openairdocs.org/files/sha256/6b/a5/6ba540d7a4686f9ebb0c0dc524a9c32ab4ebaade2e4e8bc55fea989e1252cc96
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B2421F8051802BDF86258726004DB4BC.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST09011SC

## ADs that name it (0)

None.

## Approved models (3)

- Textron Aviation Inc. 500 ([TCDS A22CE](https://openairdocs.org/tcds/A22CE))
- Textron Aviation Inc. 550 ([TCDS A22CE](https://openairdocs.org/tcds/A22CE))
- Textron Aviation Inc. S550 ([TCDS A22CE](https://openairdocs.org/tcds/A22CE))

## 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.

FAA Form 8110-2 (5/14) Page 1 of 2

Reissued on July 14, 2017 to supersede the original STC, which has been lost or misplaced.

Number: ST09011SC

Part 25 of the Federal Aviation Regulations.

Original Product – Type Certificate Number: A22CE Make: Cessna Model: S550, 550, 500 Description of Type Design Change:

Installation of a pilot’s, control wheel mounted, alternate gear horn silence switch in accordance with Sierra Drawing List SI260-000, Revision IR, dated January 25, 1994, or later FAA approved revision.

Compatibility of this design change with previously approved modifications must be determined by the installer. 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: February 24, 1994 Date Reissued: July 21, 2005; July 14, 2017 Date of Issuance: March 07, 1995 Date Amended:

Signature

Title James A. Grigg Manager, Fort Worth Aircraft Cer tification Office, Southwest Region Sierra Industries, Ltd.

122 Howard Langford Drive Uvalde, TX 78801

FAA Form 8110-2 (5/14) Page 2 of 2

Transfer the ownership of Supplemental Type Certificate Number: ST09011SC

To (Name and address of transferee)

From (Name and address of grantor)

FAA Form 8110-2 (5/14) Page 3 of 2

## Every issue (2)

- July 14, 2017: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/6b/a5/6ba540d7a4686f9ebb0c0dc524a9c32ab4ebaade2e4e8bc55fea989e1252cc96)
- July 21, 2005: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/06/c8/06c8217cf60939eb824d7aff85abad59f7a5ec62e8fc091ceb375665b3b83f2e)

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