# STC SA7975SW - Type: Supplemental type certificate - Status: Current, Reissued - Holder: RAM Aircraft Limited Partnership, United States - Description: Install vortex generators on vertical stabilizer. - Applied: December 13, 1990 - Status date: October 8, 2001 - Product: Aircraft, Small Multi-Engine - Certification basis: Part 21, Part 23 - Data sheets: [TCDS 3A25](https://openairdocs.org/tcds/3A25) - Certificate PDF: https://openairdocs.org/files/sha256/f1/fa/f1fa7b90526d4f6701cd72f9530ffa48900ca2f16b0b0675da3b794665ebf174 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9BB1EBCC33C5935585256CC20058E505.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SA7975SW ## ADs that name it (0) None. ## Approved models (3) - Cessna Aircraft Company 335 ([TCDS 3A25](https://openairdocs.org/tcds/3A25)) - Cessna Aircraft Company 340 ([TCDS 3A25](https://openairdocs.org/tcds/3A25)) - Cessna Aircraft Company 340A ([TCDS 3A25](https://openairdocs.org/tcds/3A25)) ## 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. Part 23 of the Federal Aviation R egulations. Original Product Type Certificate N umber : Option 1: Install Vortex Generators on vertical stabilizer in accordance with RAM Drawing No. 1474 Rev. B. dated March 4, 1991 or later FAA approved revision. Option 2: Same as Option 1 except no change in airspeeds; Supplemental Flight Manual not required. Option 3: Install vortex generators on vertical stabilizer and wing top surface in accordance with RAM Drawing No. 1474 Rev. B dated March 4, 1991 or later FAA approved revision. Option 4: Same as Option 3 except no change in airspeeds; Supplemental Flight Manual not required. RAM Aircraft, Limited Partnership 7505 Karl May Drive Waco, TX 76708 3A25 M ake : Cessna M odel : 335, 340, 340A Date of application : December 13, 1990 Date of issuance : February 27, 1991 Date reissued : October 08, 2001 B y direction of the A dministrator (Signature) S. Frances Cox, Manager Special Certification Office, Southwest Region (Title) FAA Form 8110-2-1(10-69) Page 2 of 4 FAA Form 8110-2-1(10-69) Page 3 of 4 N umber SA7975SW Date of Issuance: February 27, 1991 Reissuance Date: October 8, 2001 Option 1: Vortex Generator Installation on Vertical Stabilizer Only. A) Standard 335, 340 and 340A – FAA Approved Supplemental Flight Manual No. FM1001 dated April 2, 1991, is required. Compatibility of this modification with other previously approved modifications must be determined by the installer. 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. B) 340 and 340A Increased Gross Weight – This modification (STC SA7975SW) has been found to be compatible with STC SA7382SW and SA7365SW. Combined FAA Approved Supplemental Flight Manual No. FM1002 dated April 2, 1991, is required. C) 340 and 340A Increased Gross Weight and Horsepower – This modification (STC SA7975SW) has been found to be compatible with STC SA2346SW and SA4241SW. Combined FAA Approved Supplemental Flight Manual No. FM1003 dated April 2, 1991, is required. Note: Compatibility of the combined modifications listed above with future revisions to either STC must be determined by the installer. Compatibility of the combined modifications with other previously approved modifications must be determined by the installer. 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. Option 2: Vortex Generator Installation on Vertical Stabilizer Only. No change in airspeed markings; Supplemental Flight Manual not required. Aircraft installation effectivity is the same as listed in Option 1 above. Option 3: Vortex Generator Installation on Vertical Stabilizer and Wing Top Surface. A) Standard 335, 340, 340A – FAA Approved Supplemental Flight Manual No. FM1004 dated April 2, 1991, is required. Compatibility of this modification with other previously approved modifications must be determined by the installer. 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. B) 340 and 340A Increased Gross Weight – This modification (STC SA7975SW) has been found to be compatible with STC SA7382SW and SA7365SW. Combined FAA Approved Supplemental Flight Manual No. FM1005 dated April 2, 1991, is required. FAA Form 8110-2-1(10-69) Page 4 of 4 N umber SA7975SW Date of Issuance: February 27, 1991 Reissuance Date: October 8, 2001 C) 340 and 340A Increased Gross Weight and Horsepower – This modification (STC SA7975SW) has been found to be compatible with STC SA2346SW and SA4241SW. Combined FAA Approved Supplemental Flight Manual No. FM1006 dated April 2, 1991, is required. Note: Compatibility of the combined modifications listed above with future revisions to either STC must be determined by the installer. Compatibility of the combined modifications with other previously approved modifications must be determined by the installer. 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. Option 4: Vortex Generator Installation on Vertical Stabilizer and Wing Top Surface. No change in airspeed Markings; Supplemental Flight Manual not required. Aircraft installation effectivity is the same as listed in Option 3 above. -END- ## Every issue (1) - October 8, 2001: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/f1/fa/f1fa7b90526d4f6701cd72f9530ffa48900ca2f16b0b0675da3b794665ebf174) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.