# STC SA4423SW - Type: Supplemental type certificate - Status: Current, Reissued - Holder: Zee Systems, Inc, United States - Description: Installation of Freon air conditioning system. - Applied: September 8, 1980 - Status date: December 4, 1986 - Product: Aircraft, Small Multi-Engine - Certification basis: Part 21 - Data sheets: [TCDS A22CE](https://openairdocs.org/tcds/A22CE), [TCDS A27CE](https://openairdocs.org/tcds/A27CE) - Certificate PDF: https://openairdocs.org/files/sha256/ba/f2/baf26a9f7b7a0edbd6b50abaec448fbafb0ed87ebf87b1881d159e8d36c81d79 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/28920FB746B610E385256CC2000E3C64.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/SA4423SW ## ADs that name it (0) None. ## Approved models (3) - Cessna Aircraft Company 550 ([TCDS A22CE](https://openairdocs.org/tcds/A22CE)) - Cessna Aircraft Company 551 ([TCDS A27CE](https://openairdocs.org/tcds/A27CE)) - Cessna Aircraft Company S550 ([TCDS A22CE](https://openairdocs.org/tcds/A22CE)) ## 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 States of amtrica Bepartment of transportation—federal Nation administration Supplemental IKgpe Certificate tyuvmv&r' SA4423SW Zee Systems, Inc. 127 Braniff San Antonio, TX 78216 m/jd/i&^uSi&JcteAACf#vfw^%^fe ^/*^^ 25 ^j&e/ Federal Aviation tSl6aa4a&&n&. A22CE, A27CE Cessna 550, S550, 551 Installation of freon air conditioning system according to Executive Jet Works Drawing List DL 80-16, Revision C dated 5/28/85, or later FAA approved revision. FAA Approved Airplane Flight Manual Supplement dated April 1, 1981, Revision 1 dated August 26, 1985, is required. Compatibility of this modification with other previously approved modifications must be determined by the installer. *jva4^^^M/tfbr<>'vaJMuiM/wrrt^tvArv^^jfa/Mri&6Mit<'- &n'4iafes^**i>iil4'^A£&vttAfiecvJvu'Jd/ie0 ca£on,: September 8, 1980 3L&M«M*«d: 12/4/86 July 20, 1981 tjL^,™^.5/31/85; 8/26/85 Revision 2 L. B. Andriesen (Signature) Assistant Manager, Aircraft Certification Division, Southwest Region ——————————(Title)———~~~~~~~ This certificate may be transferred in accordance vailh FAR 21.77. FAA FO«M 81 10-2 (10-68) TRANSFER ENDORSEMENT Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, Slate, and <7/> code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and ^IP code) Extent of Authority (if licensing agreement): Signature of grantor (In ink): ## Every issue (1) - December 4, 1986: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/ba/f2/baf26a9f7b7a0edbd6b50abaec448fbafb0ed87ebf87b1881d159e8d36c81d79) --- 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.