# STC SA425EA-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: American Airlines Inc, United States
- Description: Install a standby horizon system.
- Applied: May 21, 1967
- Status date: September 15, 1967
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE)
- Certificate PDF: https://openairdocs.org/files/sha256/19/10/19102296a8cba86435aadf74d65d9f8aafaa0f91cc30669b3307bce31a434936
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E5565C0F0F641E5686257DFC0058EF0A.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA425EA-D

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 727 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

Federal Aviation Agency Supplemental Type Certificate Number SA 425EA-D This certificate issued to: American Airlines, Inc.

Maintenance & Engineering Center Tulsa, oklahoma Part 25| of the Federal Aviation Regulations.

Original Product - Type bertificate Numben: АЗИЕ Make: Boeing Model: 727-23 Description of Type Design Change:

1. Install a standby horizon system in accordance with American Airlines ECO H.00949 and drawings listed in the ECO.

This approval should not be 'extended to other specific aircraft of this model on which other approved modifications are incorporated, unless it is determined that interrelationship between this change and any of those other previously incorporated approved modifications will introduce no adverse effect upon the airworthiness of that aircraft.

Date of Application: May 21, 1967 Date Reissued:

Date of Issuance: Sept. 15, 1967 Date Amended:

By limelign of the slip she senten UNITED STATES, O AMERICA Keene DAS Coordinator (Title) 47 FAA FORM 8110-2 (1-66) 0052-657-6000

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and Z1P code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and ZIP code) Exent of Authority (if licensing agreement) :

Signature of grantor (1n ink) :

## Every issue (1)

- September 15, 1967: Issued, Current. [certificate](https://openairdocs.org/files/sha256/19/10/19102296a8cba86435aadf74d65d9f8aafaa0f91cc30669b3307bce31a434936)

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