# STC SA3129SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Mitchell Automatic Flight System Model AK590 consisting of Century III
Autopilot with Optional Radio Coupler and Glide Slope Coupler
- Applied: March 4, 1976
- Status date: June 5, 1984
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A20SO](https://openairdocs.org/tcds/A20SO)
- Certificate PDF: https://openairdocs.org/files/sha256/31/72/3172606b7670e262ef9aa2ad0b280a75fedda585cea19a78b4df232d08c9a402
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/BECAECFE6E21877585256CC2000A9436.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3129SW-D

## ADs that name it (0)

None.

## Approved models (1)

- Piper Aircraft Inc. PA-31-325 ([TCDS A20SO](https://openairdocs.org/tcds/A20SO))

## 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.

Bcpartmenc of transportation federal atrtation administration Supplemental t^pe Certificate * s(t4Jf4-t-{4f-& SA3129SW-D Century Flight Systems, Inc.

P.M. 1195 P. 0. Box 610 Mineral Wells, TX 76067 ^A^^iJ/i^^ieA^^n^^^/i^^f/fft^n 3 ^2^f Civil Air A8EA Piper PA-31-325 Installation of Mitchell Automatic Flight System Model AK590 consisting of Century III Autopilot with Optional Radio Coupler and Glide Slope Coupler according to Bulletin No. 714, dated 3-3-76 and Master Drawing List No. 87A841, dated 3-3-76.

FAA/DAS Approved Airplane Flight Manual Supplement, P/N 68S352, dated 4-15-76 is required.

Placard, P/N 13A660 is required.

^'b^dSSjEeFS? ^e^taile/^* °ther P^iously approved modifications <-Jn^J>eA*ty!ica&;a0M-4fa-A4^ifit^i/n&<ch^*irn<L£A i&' &if 4-aJtA Jt*p-j^iAwva/jA^a//<vt'rrutA<n- vnsdfef/MnM'A*A&~ 6-05-84, Revision 1 -Jjg& ** tA 4—15—76 -S 0£r atrtr /ufea •'

• J.U' Don P. WatSOn (Signature) Manager, Aircraft Certificatioh Division Southwest Region (Title) fine of not exceeding 11,000, or imprisonment not exceeding 3 j/ean, or both.

This certificate may be transferred in accordance u-ilh FAR 21.17.

FAA tout • 110-J (10-61)

• NSTRUCTIONS: The .ranker endorsement be.ow may be used to notify the appropriate FAA Kepona. Office of t he transfer of this 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) _ (Ct<):

from (Name of grantor) (Print or type).

(Address of grantor) __ (Xumkf *i>J Ureil/ Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- June 5, 1984: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/31/72/3172606b7670e262ef9aa2ad0b280a75fedda585cea19a78b4df232d08c9a402)

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