# STC ST9426SC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: American Airlines Inc, United States
- Description: Installation of a Thommen Revue 8-day mechanical wind up clock.
- Applied: January 21, 1999
- Status date: May 27, 1999
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A6WE](https://openairdocs.org/tcds/A6WE)
- Certificate PDF: https://openairdocs.org/files/sha256/53/db/53db16e472da62a522a87e1d5ffc03075c6384805db836bfb41ebee64a241a37
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EA377F939CD75A9A85256CC3000374DF.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST9426SC-D

## ADs that name it (0)

None.

## Approved models (2)

- The Boeing Company DC-9-82 (MD-82) ([TCDS A6WE](https://openairdocs.org/tcds/A6WE))
- The Boeing Company DC-9-83 (MD-83) ([TCDS A6WE](https://openairdocs.org/tcds/A6WE))

## 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 ST 9426 SC-D This certificate issued to: P. O. Box 582809 American Airlines, Inc.

MD 176 Tulsa, Oklahoma 74158-2809 Certifies that the change in the type design for the following product with the limitations and conditions therefor as specified hereon meets the airvorthiness reguirements of Part 25 of the Federal A viation Regulations:

Original Product -Iype bentificato Numben: A6WE Make: McDonnell Douglas Model: DC-9-82/-83 Description of Type Design Change:

Installation of a Thommen Revue 8-day mechanical wind-up clock in accordance with American Airlines Engineering Change Order (ECO) K2192AX dated 5/7/99 or later DASISW approved revision.

This approval should not be incorporated in any aircraft of this specific model until compatibility of this modification with previously approved modifications has been 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: 1/21/99 Date Reissued:

Date of Issuance: 5/27/99 Date Amended:

FEDERAL AVIATIO By Direction of the Administrator TOMINISTRATO E. J. Grewe DAS1SW Coordinator (Title)

47.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number_ to (Name of transferee) (Address of transferee) (Number and street) (City, State, and ZIP code) from (Name of grantor) (Print or type) (Address of grantor) (Number & street) (City, State, and ZIP code) Extent of Authority (if licensing agreement):

Date of Transfer:_ Signature of grantor (In ink):

## Every issue (1)

- May 27, 1999: Issued, Current. [certificate](https://openairdocs.org/files/sha256/53/db/53db16e472da62a522a87e1d5ffc03075c6384805db836bfb41ebee64a241a37)

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