# STC ST12337AT - Type: Supplemental type certificate - Status: Current, Issued - Holder: Avionics Support Group - Description: Installation of Collins Aerospace SAT-2200 Inmarsat Satellite Data Unit (SDU) part number 822-2556-102 or 822-2556-103 SATCOM SDU utilizing existing provisions - Status date: March 23, 2026 - Data sheets: A20WE, A20WE - Certificate PDF: https://openairdocs.org/files/sha256/d9/38/d9382e384c937b9b4f9a766b7741e80c994ead54bf51d07c2fc7a524b0ca37bd - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID130714203020260325161729.0001 - Page: https://openairdocs.org/stc/ST12337AT ## ADs that name it None. ## Approved models (2) - The Boeing Company 747-8 Series (TCDS A20WE) - The Boeing Company 747-8F Series (TCDS A20WE) ## 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. ST12327AT Avionics Support Group 13155 SW 132 Avenue Miami, FL 33186 Part 25 A20WE The Boeing Company 747-8 Series, 747-8F Series See Continuation Sheet Page 3 12/11/2024 03/23/2026 (for) Michael P. Linegang Manager, East Certification Branch Compliance and Airworthiness Division Aircraft Certification Service 4 Installation of Collins Aerospace SAT-2200 Inmarsat Satellite Data Unit (SDU) part number 822-2556-102 or 822-2556-103 SATCOM SDU utilizing existing provisions in accordance with Avionics Support Group Master Data List 224158-MDL, Revision B, dated March 12, 2026 or later FAA approved revisions. Instructions for Continued Airworthiness (ICA) document 224158-ICA Revision A dated February 27, 2026 or later FAA accepted revision shall be made available to the operator at the time of installation. the Federal Aviation Regulations. ST12327AT 03/23/2026 ST12327AT 03/23/2026 Limitations and Conditions : 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 747-8 and 747-8F airplanes is as follows: a. The type certification basis for Boeing 747-8 and 747-8F airplanes is shown on TCDS A20WE 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, December 11, 2024 is based upon part 25 as amended by Amendment 25-152. 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 : ST12327AT 03/23/2026 Certification Basis (Continued) : Regulations at the latest amendment 25-0 through 25-152 §25.1301(a)(b)(c) §25.1307(c) §25.1309(a)(b)(e) §25.1353(a) §25.1357(a) §25.1360(a)(b) §25.1431(a)(c) §25.1529 §25.1541(a) 14 CFR Part 26 Regulations None --------------------------END--------------------------- 4 4 Add Page ## Every issue (1) - March 23, 2026: Issued, Current. [certificate](https://openairdocs.org/files/sha256/d9/38/d9382e384c937b9b4f9a766b7741e80c994ead54bf51d07c2fc7a524b0ca37bd) --- From OpenAirDocs.org, an independent open copy of FAA data. Only the Federal Register edition on govinfo.gov is the official legal text of an AD.