# STC SA3388SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Installation of Mitchell automatic flight system Model YK849 consisting of a yaw damper system.
- Applied: May 4, 1981
- Status date: August 15, 1983
- Product: Aircraft, Small Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A20SO](https://openairdocs.org/tcds/A20SO)
- Certificate PDF: https://openairdocs.org/files/sha256/2c/2e/2c2eaec37dd9b0767c6ba778bb0fa798f277527b79b2543c3232915de3c278f8
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1574DFE80EE2BF6985256CC2000A978B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3388SW-D

## ADs that name it (0)

None.

## Approved models (4)

- Piper Aircraft Inc. PA-31 ([TCDS A20SO](https://openairdocs.org/tcds/A20SO))
- Piper Aircraft Inc. PA-31-300 ([TCDS A20SO](https://openairdocs.org/tcds/A20SO))
- Piper Aircraft Inc. PA-31-325 ([TCDS A20SO](https://openairdocs.org/tcds/A20SO))
- Piper Aircraft Inc. PA-31-350 ([TCDS A20SO](https://openairdocs.org/tcds/A20SO))

## What the certificate says

This is OCR from the scanned FAA certificate. OCR can misread letters and numbers.

United States of America Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number: SA338354-7 This certificate issued to: Century Flight Systems, Inc.

F.M. 1195 P. O. Box 610 Mineral Wells, TX 76067 Purt 3 of the CIV11 AIX Regulations.

Original Product -Iype bestificate Number: A2050 Make: Piper Model: PA-31, PA-31-300, PA-31-325, PA-31-350 Description of Type Design Change:

Installation of Mitchell Automatic Flight System Model YK849 consisting of a Yaw Damper System per Bulletin No. 987, dated 4-20-81 and Master Drawing List No. 87A1097, dated 4-20-81 (28 volt system) and/or later FAA approved revision.

FAA/DAS Approved Airplane Fl1ght Manual Supplement, P/N 68S925, dated 5-6-81 and/or later FAA approved revision.

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

5-6-81 I ate unended:

FEDERAL AVIATION By Direction of the Administrator Don P. 1B Watson speak TAMIN STRATIO Manager, Aircraft Cértification Division Southwest Region (Title)

47.

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) Extent of Authority (if licensing agreement):

Signature of grantor (in ink): - +11 8 r. 0~. 1080-262-180

## Every issue (1)

- August 15, 1983: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/2c/2e/2c2eaec37dd9b0767c6ba778bb0fa798f277527b79b2543c3232915de3c278f8)

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