# STC SA405SW

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Signature Flight Support Corporation, United States
- Description: Installation of propeller autofeathering system and mixture indicator.
- Applied: May 21, 1964
- Status date: August 31, 2000
- Product: Aircraft, Large Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A-723](https://openairdocs.org/tcds/A-723)
- Certificate PDF: https://openairdocs.org/files/sha256/dd/c7/ddc7ab8ace27f7484b49cbbcbf788f8aadfe2d05f80c1702d397d3db2a88fbf4
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/16595DF2C2CB144286257DF900793C0B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA405SW

## ADs that name it (0)

None.

## Approved models (1)

- Lockheed Martin Aeronautics Company 18 ([TCDS A-723](https://openairdocs.org/tcds/A-723))

## 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.

JHnttcb J&tates ©f <Amwtca JBeparlmml at '(Erattspmrialtoit - Jlfcbcral (Herttftcate SA405SW Signature Flight Support Corporation, a Delaware Corporation 7511 Lemmon Avenue, Hangar C Dallas, TX 75209 Civil Air 723 Lockheed 18 Installation of propeller autofeathering system and mixture indicator in accordance with Drawing List SD603000-4J dated 4/25/65, or later FAA approved revision.

1. FAA Approved Airplane Flight Manual Supplement dated 9/16/64 is required for Lockheed Model 18 aircraft.

2. FAA Approved Airplane Flight Manual Supplement dated 7/31/64 is required for Howard Model 250 aircraft.

3. This STC is part of the basic H250 Tri-Gear configuration and is covered by the flight manual for this model.

4. Compatibility of this modification with other previously approved modifications must be determined by the installer.

21, 1964 01, 1965

•9/4/92; 12/21/98; 8/31/00 February 25, 1982 Rev. 7 S. Frances Cox Manager, Special Certification Office, Southwest Region (Title)———————————————

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and £IP code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street j Cil)1, Slate, and ^1P code) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- August 31, 2000: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/dd/c7/ddc7ab8ace27f7484b49cbbcbf788f8aadfe2d05f80c1702d397d3db2a88fbf4)

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