# STC SA4-1578

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: SOUTHWESTERN AERO EXCHANGE INC., United States
- Description: Removal of the main cabin entrance door and installation of stair door.
- Applied: June 29, 1961
- Status date: February 24, 2006
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A-765](https://openairdocs.org/tcds/A-765)
- Certificate PDF: https://openairdocs.org/files/sha256/67/4f/674fe6f9a7504ab6c3b39ea6106a6a6d67c62ed785394b1b448a0b5583194a51
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/FE1897465CDCADF78625712600546B66.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA4-1578

## ADs that name it (0)

None.

## Approved models (2)

- Raytheon Aircraft Company D18C ([TCDS A-765](https://openairdocs.org/tcds/A-765))
- Raytheon Aircraft Company D18S ([TCDS A-765](https://openairdocs.org/tcds/A-765))

## 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.

This Certificate issued to Southwestern Aero Exchange, Inc.

18502 East 108th Street, North Owasso, OK 74055-8124

Part CAR 3 of the Civil Air Regulations.

A-765 BEECH D18C, D18S, C-45F, X45H, RX-45F, RX-45H, SNB-5 Description of Type Design Change: Removal of the main cabin entrance door and installation of star door in accordance with Volition Aviation, Inc. Drawing No. 61100, Revision “A” to Sheets 1, 2, 3, 4, and 5.

Limitations and Conditions: 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. This modification does not affect the approved gross weight of any of the above models provided no other structural modifications have previously been incorporated in the same area for other reasons.

This certificate and the supporting data, which is the basis for approval, shall remain in effect until surrendered, suspended, revoked or a termination date is otherwise established by the Administrator of the Federal Aviation Administration.

Date of application: June 29, 1961

Date of issuance: August 11, 1961

Date reissued: July 6, 1967; Jan. 23, 1998;

February 24, 2006

Date amended: Nov. 10, 1961; Feb. 13, 1998;

Feb. 14, 1963

( Signature)

Manager, Technical & Administrative Support Staff, Los Angeles Aircraft Certification Office ( Title)

## Every issue (1)

- February 24, 2006: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/67/4f/674fe6f9a7504ab6c3b39ea6106a6a6d67c62ed785394b1b448a0b5583194a51)

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