# STC SA3350WE-D - Type: Supplemental type certificate - Status: Current, Reissued - Holder: United Airlines Inc, United States - Description: The air data system is revised in accordance with United Air Lines, DAS-1-WE Approved Drawing List No. 3350 dated July 20, 1979, or later FAA approved revisions to the following configuration: 1. The Captain's and First Officer's altimeters are Harowe P/N 2050 Series electric indicators. 2. The No. 1 air data computer is a Honeywell P/N HG180U-742 (727-222 only) or a United Air Lines P/N 9F-9058-505 (727-22, -22C only). 3. The No. 2 air data computer is a Harowe P/N 4019-1, -2, or -5. On the 727-222 only, a Honeywell HG180OU-742, HG180V2-9F9058-506, HG180V1-9F9057-504. - Applied: August 23, 1977 - Status date: November 30, 2011 - Product: Aircraft, Large Multi-Engine - Certification basis: Part 21 - Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE) - Certificate PDF: https://openairdocs.org/files/sha256/2f/39/2f39e0ee595f4d1dadf733ebc0842bf2503672696b60eb2c216a249bfe0d6edf - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/11AA3D73365D61D886257991006FC135.0001 - DRS record last changed: December 5, 2025 - Page: https://openairdocs.org/stc/SA3350WE-D ## ADs that name it (0) None. ## Approved models (3) - The Boeing Company 727 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE)) - The Boeing Company 727-200 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE)) - The Boeing Company 727C Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE)) ## 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. 600 Jefferson Street Houston, Texas 77002 Part 4b of the Civil Air Regulations Original Product Type Certificate Number : A3WE Boeing 727-22, -22C, -222 Description of Type Design Change: The air data system is revised in accordance with United Air Lines, DAS-1-WE Approved Drawing List No. 3350 dated July 20, 1979, or later FAA approved revisions to the following configuration: 1. The Captain’s and First Officer’s altimeters are Harowe P/N 2050 Series electric indicators. 2. The No. 1 air data computer is a Honeywell P/N HG180U-742 (727-222 only) or a United Air Lines P/N 9F-9058-505 (727-22, -22C only). 3. The No. 2 air data computer is a Harowe P/N 4019-1, -2, or -5. On the 727-222 only, a Honeywell HG180OU-742, HG180V2-9F9058-506, HG180V1-9F9057-504. Limitations and Conditions: This approval should not be extended to other aircraft of this model on which other previously approved modifications are incorporat ed unless it is determined that the interrelationship between this change and any of those other previously approved modifications will introduce no adverse effect upon the airworthiness of that 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. This certificate and the supporting data, which is the basis for approval, shall remain in effect until surrendered, suspended, revoked or a termination date is otherwise established by the Administrator of the Federal Aviation Administration. Date of application: August 23, 1977 Date of issuance: October 27, 1977 Date reissued: November 30, 2011 Date amended: March 13, 1978, July 20, 1979, December 1, 1980 ( Signature) Haifa Haj-Eid Supervisor, Technical &Administrative Support Staff Los Angeles Aircraft Certification Office ( Title) Number SA3350WE-D 4. HG180R23-6F14735-501 air data computer may be installed. 5. A standby pneumatic indicator Kollsman P/N 3549 Series or P/N 3811 Series is installed. United Air Lines FAA Approved Airplane Flight Manual Supplement to Boeing Flight Manual Document No. D6- 8727 dated February 15, 1978 or to Boeing Flight Manual Document No. D6-8728 dated October 1, 1977 or later FAA approved revision is required as part of this installation. -END- ## Every issue (1) - November 30, 2011: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/2f/39/2f39e0ee595f4d1dadf733ebc0842bf2503672696b60eb2c216a249bfe0d6edf) --- 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.