# STC ST9423SC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: American Airlines Inc, United States
- Description: Install new passenger seats equipped with powerports and floor proximity emergency escape path lighting in a 14 First and 125 Coach class configuration.
- Applied: December 11, 1998
- Status date: January 15, 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/bb/9a/bb9a2741c87ece29f23145459b804d2300f1816fd128a74b27f64dc15d3d32a1
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/0B8F368DAEE717C385256CC3000374DD.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST9423SC-D

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company DC-9-82 (MD-82) ([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 9423 SC-D This certificate issued to: American Airlines, Inc.

P. O. Box 382809, MD 208 Tulsa, Oklahoma 74158-2809 Certifies that the change in the type design for the following product with the limitations and conditions therefonas specified hereon meets the airvorthiness reguirements of Part 25 of the Federal Aviation Regulations.

Original Product -Type-bertificate Numben: AGWE Make: McDonnell Douglas Model: DC-9-82 Description of Type Design Change:

Install new Passenger seats equipped with powerports and floor proximity emergency escape path lighting in a 14 First and 125 coach class configuration in accordance with Engineering change orders Eco K2109 dated 12/10/98 and one prototype revision forms 7721-6 dated 1/14/99 or later DAS1SW approved revision of each.

This approval should not be incorporated in any aircraft of this specific model until compatibility of this modification with other previously approved modifications has been determined by the installer. If the holder agrees to permit another person to use this certificate to alter a product, the holder shall give the other person written evidence of that permission.

December 11, 1998 Date of Issuance: Date Amended:

January 15, 1999 FEDERAL AVIATION By Direction of the Administrator & 1 Juves E. J. Grewe (Signature)

OMINISTRAILO DASISW Coordinator

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):

Signature of grantor (In ink):

## Every issue (1)

- January 15, 1999: Issued, Current. [certificate](https://openairdocs.org/files/sha256/bb/9a/bb9a2741c87ece29f23145459b804d2300f1816fd128a74b27f64dc15d3d32a1)

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