# STC SA3133SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Mitchell Automatic Flight System Model AK599 consisting of Century III
Autopilot with Optional Radio Coupler and Glide Slope Coupler
- Applied: April 15, 1976
- Status date: June 5, 1984
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS 1A10](https://openairdocs.org/tcds/1A10)
- Certificate PDF: https://openairdocs.org/files/sha256/15/f0/15f0d2eb67e24ce6e9b694badd3d32461a95e53661fe7aed82019bb7ddf95f95
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/3F81E02B98B5065585256CC2000A944A.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3133SW-D

## ADs that name it (0)

None.

## Approved models (3)

- Piper Aircraft Inc. PA-23-235 ([TCDS 1A10](https://openairdocs.org/tcds/1A10))
- Piper Aircraft Inc. PA-23-250 ([TCDS 1A10](https://openairdocs.org/tcds/1A10))
- Piper Aircraft Inc. PA-E23-250 ([TCDS 1A10](https://openairdocs.org/tcds/1A10))

## 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.

Bepartmtnt of transportation —federal atriation administration Supplemental TlCgpe Certificate ^Sle&tAla&olyiwmvefr' SA3133SW-D Century Flight Systems, Inc.

P.M. 1195 P. 0. Box 610 Mineral Wells, TX 76067 JifoJ'ufeJdeA^amjf^jA^ V 1A10 Piper PA-23-235, PA-23-250, PA-E23-250 njae< :

Installation of Mitchell Automatic Flight System Model AK599 consisting of Century III Autopilot with Optional Radio Coupler and Glide Slope Coupler according to Bulletin No. 723, Revision 2, dated 4-20-79 and Master Drawing List No. 87A855, Revision B, dated 4-20-79 (14 Volt System) and/or later FAA approved revisions of the above data.

Eligible on PA-23-250, S/N 27-7554181 and below and PA-E23-250, S/N 27-7554181 and below. Also eligible on PA-23-235, PA-23-250, S/N 27-7554181 and below and PA-E23-250, S/N 27-7554181 and below when modified in accordance with STC SA909WE.

FAA/DAS Approved Airplane Flight Manual Supplement, P/N 68S370, dated 5-7-76 is required and/or later FAA approved revisions of the above Supplements. Placard, P/N 13A660 isrequired.

«PPr«ved modifications 9-29-76; 4-25-79;

6-05-84, Revision 3 L/ atr Mrrttr /.u- Don P. Watson (Signature) Manager, Aircraft Certification Division Southwest Region (T,tle)

This certificate may be transferred in accordance witfi FAR 21.17.

FAAFo«M ill 0-1(10-68)

.NSTRUCTIONS: The transfer endowment be.ow may be used to notify .he appropriate FAA Kepona. Office of the transfer of Urn Supplemental Type Certificate.

The FAA will reissue 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) __ from (Name of grantor) (Print or type).

(Address of grantor) (ffumttr *n4 ttrtllj Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- June 5, 1984: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/15/f0/15f0d2eb67e24ce6e9b694badd3d32461a95e53661fe7aed82019bb7ddf95f95)

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