# STC ST11858AT - Type: Supplemental type certificate - Status: Current, Issued - Holder: Avionics Support Group, United States - Description: Installation of a dual FreeFlight Systems RA-6500 Radio Altimeter System - Applied: January 27, 2023 - Status date: January 7, 2025 - Product: Aircraft, Large Airplane - Certification basis: Part 25 - Data sheets: [TCDS A16WE](https://openairdocs.org/tcds/A16WE) - Certificate PDF: https://openairdocs.org/files/sha256/b5/98/b598021fa1b411a9878c321aa2225c940086d1cb6c4a802e68647ecbcaff9e14 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID159740621120250610143817.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/ST11858AT ## ADs that name it (0) None. ## Approved models (3) - The Boeing Company 737-300 Series ([TCDS A16WE](https://openairdocs.org/tcds/A16WE)) - The Boeing Company 737-400 Series ([TCDS A16WE](https://openairdocs.org/tcds/A16WE)) - The Boeing Company 737-500 Series ([TCDS A16WE](https://openairdocs.org/tcds/A16WE)) ## 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. Title: (for) Christina M. Underwood Manager, East Certification Branch Compliance and Airworthiness Division Aircraft Certification Service ST11858AT Avionics Support Group 13155 SW 132 Avenue Miami, FL 33186 Part 25 the Federal Aviation Regulations. A16WE The Boeing Company 737-300/-400/-500 Installation of a dual FreeFlight Systems RA-6500 Radio Altimeter System per Master Drawing List 223173-MDL Revision A dated November 1, 2024 or later FAA approved revision. Instructions for Continued Airworthiness 223173-ICA Revision IR dated October 6, 2023 or later FAA approved revision shall be made available to the operator at the time of installation. See Continuation Sheet Page 3 July 27, 2023 January 7, 2025 4 ST11858AT 4 ST11858AT Limitations and Conditions (Continued): 1. The installer must determine whether this design change is compatible with previously approved modifications. 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. Certification Basis: Based on 14 CFR 21.115 and 21.101, and the FAA policy for significant changes in FAA Order 8110.48, the certification basis for Boeing 737-300/-400/-500 series aircraft is as follows: a. The type certification basis for the Boeing 737-300/-400/-500 airplane is shown on TCDS A16WE for parts not changed or not affected by the change. b. The certification basis for parts changed or affected by the change since the reference date of application, July 27, 2023 is based upon part 25 as amended by Amendment 25-148. Based on 14 CFR 21.115 and 21.101, and the FAA policy for significant changes in FAA Order 8110.48, the certification basis for this modification was determined to be: ST11858AT Certification Basis (Continued): Regulations at the latest amendment 25-0 through 25-148: §25.29 §25.611 §25.869(a)(1)(3) §25.981(a)(3) §25.1301(a1-a4) §25.1307(c) §25.1309 §25.1351(a) §25.1353(a) §25.1357(a) §25.1360(a)(b) §25.1431(a)(c) §25.1529 §25.1541(a) §25.1729 §H25.1 §H25.5 Regulations at an intermediate amendment: None Regulations at the amendment level in TCDS A16WE: None 14 CFR Part 26 Regulations: Referencing §26.11(d), the Applicant has elected to reference §25.1729 which accomplishes the intent of §26.11 regarding requirements for EWIS Instructions for Continued Airworthiness. Additionally no structural alterations were accomplished as part of this STC, and as such there is no requirement that §26.47 be part of the certification basis. --------------------------END--------------------------- January 7, 2025 ## Every issue (1) - January 7, 2025: Issued, Current. [certificate](https://openairdocs.org/files/sha256/b5/98/b598021fa1b411a9878c321aa2225c940086d1cb6c4a802e68647ecbcaff9e14) --- 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.