STC SA01980CH

Part 3 of the Civil Air Regulations.

(See Type Certificate Data Sheet No. A3SW for complete certification basis)

Original Product--Type Certificate Number: A3SW Make: Thrush Aircraft Inc .

Model: S2R Description of Type Design Change:

Replacement of an existing Pratt and Whitney Model WASP S3H1 engine and Hamilton Standard Model 12D40 propeller with a Pratt and Whitney Model WASP S3H1-G engine and Hamilton Standard propeller with model 3D40 hub and blade model 6631A-S or model 23D40 hub with blade model 6601A-S, 7005A-S, or 7035A-S in accordance with “FAA Approved Installation Manual for the Installation of a Pratt & Whitney 1340 Geared Engine and Propeller on the Aero Commander S2R Thrush Airplane,” Revision 1, Dated November 14, 2007, FAA Approved March 17, 2008 or later FAA approved revision.

1. FAA Approved Airplane Flight Manual Supplement dated July 18, 2003, FAA approved August 12, 2004 or later approved revision for the Thrush Aircraft, Inc, Model S2R.

2. If the holder agrees to permit another person to use this certificate to alter the product, the holder shall give the other person written evidence of that permission.

3. Compatibility of this design change with previous modifications must be determined by the installer.

Larson Ag. Inc.

Box 139 Stephen, MN 56757 Date of application : February 20, 2004

Date of issuance : August 16, 2004

Date reissued : October 1, 2004, September 29, 2006

Date amended : May 23, 2008

( Signature) Thaddeus D. Krolicki, Jr.

Manager, Propulsion Branch Chicago Aircraft Certification Office

( Title)

FAA FORM 8110-2-1(10-69) PAGE 3 of 3 PAGES

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