# STC SA2831WE-D - Type: Supplemental type certificate - Status: Current, Reissued - Holder: United Airlines Inc, United States - Description: Couple EDO Loran System to ADF Sense Antenna instead of Fin Cap (No Fin Cap on UAL B720) in accordance with COA-4-1724 Master Drawing List, ER 2, or later FAA approved revisions. Airplane to be test flown. - Applied: March 6, 1975 - Status date: November 30, 2011 - Product: Aircraft, Large Multi-Engine - Certification basis: Part 21 - Data sheets: [TCDS 4A28](https://openairdocs.org/tcds/4A28) - Certificate PDF: https://openairdocs.org/files/sha256/8e/2a/8e2add131c864eb293d7521f92b54044159f0180959a0939ba1be853e003cdab - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A197E6C29D25D1B58625799600746D3F.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SA2831WE-D ## ADs that name it (0) None. ## Approved models (1) - The Boeing Company 720 Series ([TCDS 4A28](https://openairdocs.org/tcds/4A28)) ## 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. This Certificate issued to United Air Lines, Inc. 600 Jefferson Street Houston, Texas 77002 Part 4b of the Civil Air Regulations. Original Product Type Certificate Number : 4A28, Rev. A Make: Boeing Model: 720-022 Description of Type Design Change : Couple EDO Loran System to ADF Sense Antenna instead of Fin Cap (No Fin Cap on UAL B720) in accordance with COA-4-1724 M aster Drawing List, ER 2, or later FAA approved revisions. Airplane to be test flown. Limitations and Conditions : This approval of this change in type design applies basically to Boeing 720-022 only. This approval should not be exte nded to other aircraft of this mode l on which other previously approved modifications are incorporated unless it is determined by the installer that the interrelationship between this change and any of those other previously approved modificati ons will introduce no adverse effect upon the airworthiness of the aircraft. A copy of this STC must be included in the permanent records of th e modified aircraft. 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. Date of application : March 6, 1975 Date of issuance : March 16, 1975 Date reissued : November 30, 2011 ( Signature) Haifa Haj-Eid Supervisor, Technical & Administrative Support Staff Los Angeles Aircraft Certification Office ( Title) Transfer the ownership of Supplemental Type Certificate Number to (Name of transferee) (Address of transferee) (Number and street) (City, State, and ZIP Code) from (Name of grantor) (Print or type) (Address of grantor) (Number and street) (City, State, and ZIP Code) Signature of grantor (In ink): U.S. GPO 1987-763-28 ## Every issue (1) - November 30, 2011: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/8e/2a/8e2add131c864eb293d7521f92b54044159f0180959a0939ba1be853e003cdab) --- 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.