STC SA8386SW-D

Department of Transportation Federal Aviation Administration Supplemental Type Certificate Number 5A833654-0 This coolificate, issuad lo S-TEC Corporation 946 Pegram Mineral Wells, TX 76067 Port 3 of the CIVIl Air Rogulations Original Product -Typobontificato Numbon: 2A4 Make: Twin Commander Model: 680-E Description of Type Design Change:

installation ot S-ltc Yaw Damper System, Model Si-529, according to Bulletin No.

629, Revision 1, dated 9-11-96 and Master Drawing List No. 92677, Revision A, datec 9-11-96 or later FAA Approved revisions of the above data (28 Volt System).

1. FAA/DAS Approved Airplane Flight Manual Supplement, P/N 891057, dated 4-29-94 is required for Twin Commander Models 680-E and 720 or later FAA Approved revisions of the above supplement.

(See Continuation Sheet, Page 2, a part of this STC.)

Thomas DAS Staff Coordinator, DAS 5 SW (Title)

This certificate may be transferred in accordance with FAR 21.17.

FAN FoR 8110-2 (10-681

Hred Saces of Amera Department of Transportation Federal Aviation Administration Supplemental Type Certificate (Continuation Sheet) Number: SA838654-D, Revision 1 Limitations and Conditions: (con't.)

2. FAA/DAS Approved Airplane Manual Supplement, P/N 891057, Revision 1, dated 9-18-96 is required for Twin Commander Model 680-E or later FAA Approved revisions of the above supplement.

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

or hith FAN FORM 911ULZ-1 (10-68) This certificate may be transferred in accordance with I'll .I.t?

TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number — to (Name of transferee) (Address of transferee) (Number and street) (City, Stale, and ZIP code) from (Name of grantor) (Print or type) _ (Address of grantor) (Number and street) (City, Stale, and ZIP code) Extent of Authority (if licensing agreement): - Date of Transfer:

Signature of grantor (In ink): _