# STC SA3231SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Mitchell automatic flight system model AK661 consisting of Century III autopilot with optional radio coupler and glide slope coupler.
- Applied: September 6, 1977
- Status date: December 7, 1983
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A15](https://openairdocs.org/tcds/3A15)
- Certificate PDF: https://openairdocs.org/files/sha256/e3/b4/e3b457d578cf66f528bc87d171ba5759bec4ddc9df54e616217106ac018fc0e1
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C571ED8C3834630385256CC2000A959E.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA3231SW-D

## ADs that name it (0)

None.

## Approved models (1)

- Beechcraft Corporation F33A ([TCDS 3A15](https://openairdocs.org/tcds/3A15))

## 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.

United gtatnj of arnica Bcpartment of transportation federal 3toiation administration Supplemental "Cuje Certificate SA3231SW-D Century Flight Systems, Inc.

F.M. 1195 P. 0. Box 610 Mineral Wells, TX 76067 3 ^^^e, ClVll Air 3A15 Beech F33A Installatio/of Mitchell Automatic Flight System Model AK661 consisting of a Century III Autopilot with Optional Radio Coupler and Glide Slope Coupler according to Bulletin No. 790. Revision 1, dated 4/3/78 and Master Drawing List No. 87A966 Revision A dated 4/3/78 (28 Volt System) and/or later FAA approved revision.

1. Eligible only on Beech Model F33A, S/N CE-676 and Up

2. Pilot's Operating Handbook and FAA/DAS Approved Airplane Flight Manual Supplement P/N 68S594 dated 9/22/77 is required, or later FAA approved revision.

3. Placard P/N 13A660-1 is required.

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

• wfattitn ci foa/<-*- tJ> fn^' 9/6/77 ?/.,&• ***«*</: 4/10/78; 12/7/83 Revision 2 9/22/77 —/ a/f a titf tu/tf/ -' Don P. WatSOn (Signature) Manager, Aircraft Certification Division Southwest Region (Title)

FAA FotM 8110-2 (10-68)

INSTRUCTIONS: The tranrfer endowment below may be u,ed to notify the appropriate FAA Regional Office of the transfer of thU Supplemental Type Certificate.

The FAA will reinue the certificate in the name of the transferee and forward it to him.

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee).

(Address of transferee) _ ( .Vumttr tnJ ttrtt) from (Name of grantor) (Print or type).

(Address of grantor) ___ f .Stalt, **d ZIP code) f \itmttr tnJ limtj (Cify. Suit.

Signature of grantor (In ink):

ii < r. o n 1«««-««»•«»"

## Every issue (1)

- December 7, 1983: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/e3/b4/e3b457d578cf66f528bc87d171ba5759bec4ddc9df54e616217106ac018fc0e1)

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