# STC SA3435SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Century Automatic Flight System Model AK939 consisting of a Century 21 Autopilot
- Applied: June 16, 1985
- Status date: August 10, 1986
- Product: Aircraft, Small Airplane
- Certification basis: Part 21
- Data sheets: [TCDS A51EU](https://openairdocs.org/tcds/A51EU)
- Certificate PDF: https://openairdocs.org/files/sha256/8a/22/8a226d2330f3a5a3a9ca52cf14d08dfdcfa28f34de384d16267a838a5a736517
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E96EF22D3157234C85256CC2000A980A.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA3435SW-D

## ADs that name it (0)

None.

## Approved models (2)

- SOCATA TB 10 ([TCDS A51EU](https://openairdocs.org/tcds/A51EU))
- SOCATA TB 20 ([TCDS A51EU](https://openairdocs.org/tcds/A51EU))

## 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 grata of Stonca Bepartmenc of transportation—federal 2toiation administration Supplemental 'Cuje Certificate SA3435SW<-D Century Flight Systems, Inc.

F,M, 1195 P.O. Box 610 Mineral Wells, Texas 76067 23 ^af^tnf Federal Air <Stea4i£aZu>nA .

A31EU Socata TB-20, TB^IO Installation of Century Automatic Flight System Model AK939 consisting of a Century 21 Autopilot per Bulletin 1070, dated 8-08-85 and Master Drawing List 87A1148, dated 8-O8-85 (14 Volt System) and/or later FAA/DAS Approved Revision, FAA/DAS Approved Airplane Flight Manual Supplement, P/N 68S979, dated 9~09-85. Also Century 21 Autopilot Operator's Manual P/N 68S805, Revision (2) dated 2-01-82 and/or later FAA/DAS Revision, Compatibility of this modification with other previously approved modifications must be determined by the installer, MA4cA'^.^^ L&,*eiu«*tt : Rev, 8"10- 9-23-85 William J, DAS Staff Coordinator, DAS 7 SW (Title)

Tkis certificate may be traiufemd in accordance with FAR 21.47.

rAAFcM»IHO-2(10-»l)

he appropriate FAA Region,. Office of the transfer of thit Supplemental Type Certificate.

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

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

(Address of transferee). I Mumktr *rui strtft i from (Name of grantor) (Print or type).

(Address of grantor) Extent of Authority (if licensing agreement):

Signature of grantor (In ink):

## Every issue (1)

- August 10, 1986: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/8a/22/8a226d2330f3a5a3a9ca52cf14d08dfdcfa28f34de384d16267a838a5a736517)

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