# STC SA3955SW-D

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: American Airlines Inc, United States
- Description: Installation of a Mode S Transponder System per ECO H4077CX
- Applied: February 21, 1989
- Status date: January 1, 1990
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE)
- Certificate PDF: https://openairdocs.org/files/sha256/7e/e1/7ee1170d0b32e3879d6a86ec04aa9c9b8b490797b41d96c1f09fd40cde729636
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1016144A6296E9CD85256CC2000C5BFF.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3955SW-D

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 727-200 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.

*nited Staces of Barrica Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number SA3955SW-D This certificate issued to: American Airlines Inc. P.O. BOX 582809 MD208 Tulsa, Oklahoma 74158-2809 Part 25 of the Federal Aviation Regulations.

Original Product -Typebentificate Number: ABWE Make: BOEING Model: 727-2A7, -223, -227 Description of Type Design Change:

Installation of a Mode S Transponder System per ECO H4077CX, dated 11-1-89 or later DAS1SW approved revision.

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.

Date of Application: 02-21-89 Date Reissued:

Date of Issuance: 05-27-89 Date Amended: January 01, 1990 Amendment 1 FEDERAL AVIATION By Direction of the Administrator al. sela (Signature) TOMINISTRANO DAS1SW Coordinator (Title)

47.

FAR FoRM 8110-2 (10-68)

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 and street ) (City, State, and ZIP code ) Extent of Authority (if licensing agreement):

Signature of grantor (In ink): _

## Every issue (1)

- January 1, 1990: Amended, Current. [certificate](https://openairdocs.org/files/sha256/7e/e1/7ee1170d0b32e3879d6a86ec04aa9c9b8b490797b41d96c1f09fd40cde729636)

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