# STC SH5690NM - Type: Supplemental type certificate - Status: Current, Reissued - Holder: WSH, LLC, United States - Description: Installation of Advanced Technology Aircraft Co. engine barrier filter. - Applied: August 13, 1991 - Status date: February 5, 2022 - Product: Aircraft, Rotorcraft - Certification basis: Part 21 - Data sheets: [TCDS H1SW](https://openairdocs.org/tcds/H1SW), [TCDS H4NM](https://openairdocs.org/tcds/H4NM), [TCDS H5SO](https://openairdocs.org/tcds/H5SO), [TCDS H7SO](https://openairdocs.org/tcds/H7SO), [TCDS H3SO](https://openairdocs.org/tcds/H3SO), [TCDS H13WE](https://openairdocs.org/tcds/H13WE), [TCDS H3NM](https://openairdocs.org/tcds/H3NM), [TCDS H5NM](https://openairdocs.org/tcds/H5NM), [TCDS H1RM](https://openairdocs.org/tcds/H1RM), [TCDS H8NM](https://openairdocs.org/tcds/H8NM), [TCDS H9NM](https://openairdocs.org/tcds/H9NM) - Certificate PDF: https://openairdocs.org/files/sha256/8e/af/8eafd7c0911e36c41c2f0d32b6b5b80920b8f71a442066185d1e274f35cefe11 - Approved model list and other attachments: [AML SH5690NM.pdf](https://openairdocs.org/files/sha256/58/81/5881eea738d7c09b9cce46a1d9873cbd76774cd99d175e55ee99caebe15b39f8) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9EF99A6239012CCF8625889900602BA0.0001 - DRS record last changed: August 31, 2026 - Page: https://openairdocs.org/stc/SH5690NM ## ADs that name it (0) None. ## Approved models (11) - Bell Helicopter Textron Inc. 204B ([TCDS H1SW](https://openairdocs.org/tcds/H1SW)) - Bell Helicopter Textron Inc. UH-1E ([TCDS H4NM](https://openairdocs.org/tcds/H4NM)) - International Helicopters Inc. UH-1B ([TCDS H5SO](https://openairdocs.org/tcds/H5SO)) - Overseas Aircraft Support Inc UH-1E ([TCDS H7SO](https://openairdocs.org/tcds/H7SO)) - Richards Heavylift Helo Inc. UH-1B ([TCDS H3SO](https://openairdocs.org/tcds/H3SO)) - Rotorcraft Development Corporation UH-1B ([TCDS H13WE](https://openairdocs.org/tcds/H13WE)) - Rotorcraft Development Corporation UH-1B ([TCDS H3NM](https://openairdocs.org/tcds/H3NM)) - Rotorcraft Development Corporation UH-1E ([TCDS H5NM](https://openairdocs.org/tcds/H5NM)) - San Joaquin Helicopters UH-1B ([TCDS H1RM](https://openairdocs.org/tcds/H1RM)) - Smith Helicopters UH-1E ([TCDS H8NM](https://openairdocs.org/tcds/H8NM)) - West Coast Fabrications UH-1E ([TCDS H9NM](https://openairdocs.org/tcds/H9NM)) ## 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 America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate Number: SH5690NM This certificate may be transferred or made available to third persons by licensing agreements in accordance with 14 CFR 21. 47. The STC ’s supporting documentation (drawings, instructions, specifications, flight manual supplements, etc.) is the property of the STC holder. FAA Form 8110-2 (4/22) SUPERSEDES PREVIOUS EDITION Page 1 of 3 Part 21 of the Federal Aviation Regulations. Description of Type Design Change: Installation of Advanced Technology Aircraft Company (AT AC) engine barrier filter in accordance with ATAC installation instructions and drawings as listed on the FAA AML of this Supplemental Type Certificate (STC), or later FAA -approved revisions. This STC is issued for use in the restricted category only, and the rotorcraft must be operated accordingly with the AT AC engine barrier filter installed. Limitations and Conditions: Approval of this change in type design applies to the models shown on AML SH5690NM only. This approval should not be extended to other rotorcraft of these models on which other previously approved modifications are incorporated unless it is determined that the relationship between this change and any of those other previously approved modifications, including changes in type design, will introduce no adverse effect upon the airworthiness of that rotorcraft. A copy of this certificate, continuation sheet, FAA AML SH5690NM dated March 13, 1992, or later FAA-approved revision, must be maintained as part of the permanent records for the modified rotorcraft. *See continuation sheet page 3 of 3. This certificate issued to: WSH, LLC 3255 S. Bodenburg Loop Palmer, Alaska 99645 Original Product Type Certificate Number: See attached FAA Approved Model List (AML) No. SH5690NM for list of approved rotorcraft models and applicable airworthiness regulations. Date of Application: August 13, 1991 Date Reissued: Dec. 5, 2011, Feb. 5, 2022 Date of Issuance: March 13, 1992 Date Amended: Title: Aviation Safety Acting Manager, Technical & Administrative Support Section, Los Angeles ACO Branch United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate Number: SH5690NM This certificate may be transferred or made available to third persons by licensing agreements in accordance with 14 CFR 21. 47. The STC ’s supporting documentation (drawings, instructions, specifications, flight manual supplements, etc.) is the property of the STC holder. FAA Form 8110-2 (4/22) SUPERSEDES PREVIOUS EDITION Page 2 of 3 United States of America Department of Transportation - Federal Aviation Administration Supplemental Type Certificate Number: SH5690NM This certificate may be transferred or made available to third persons by licensing agreements in accordance with 14 CFR 21. 47. The STC ’s supporting documentation (drawings, instructions, specifications, flight manual supplements, etc.) is the property of the STC holder. FAA Form 8110-2 (4/22) SUPERSEDES PREVIOUS EDITION Page 3 of 3 WSH, LLC Issued: March 13, 1992 Reissued: December 5, 2011; February 5, 2022 Amended: 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. The conditions and limitations of the Type Data Sheets listed in FAA AML SH5690NM apply except where superseded by the following: Restricted Category: This STC is issued in the restricted category, and the rotorcraft must be operated accordingly when the ATAC engine barrier filter is installed. Outside Air Temperature/Visible Moisture: Flight in visible moisture with an outside temperature below 40°F and the ATAC engine barrier filter element installed is prohibited. Required Placards: CAUTION: FLIGHT IN VISIBLE MOISTURE WITH OAT BELOW 40°F **AND ENGINE INLET FILTER ELEMENT IN PLACE IS PROHIBITED** - END - ### AML SH5690NM.pdf **FAA APPROVED MODEL LIST (AML) SH5690NM FOR** ENGINE BARRIER FILTER 1 of 1 ISSUE DATE: March 13, 1992 **ITEM** **ROTORCRAFT MAKE** **ROTORCRAFT MODEL** **ORIGINAL** **TC NUMBER** **CERTIFICATION** **BASIS FOR** **ALTERATION AFM** **SUPPLEMENT DATE** **FAA APPROVED** **DRAWING/DRAWING LIST AML** AMENDMENT DATE Drawing Revision* 1. Bell 204B H1SW 21.25 3/13/92 204 NR 2/12/92 3/13/92 2. Bell UH-1B H3NM 21.25 3/13/92 204 NR 2/12/92 3/13/92 3. Garlick UH-1B H13WE 21.25 3/13/92 204 NR 2/12/92 3/13/92 4. Hawkins & Powers UH-1B H1RM 21.25 3/13/92 204 NR 2/12/92 3/13/92 5. Hercules UH-1E H5NM 21.25 3/13/92 204 NR 2/12/92 3/13/92 6. International Helicopters, Inc. UH-1B H5SO 21.25 3/13/92 204 NR 2/12/92 3/13/92 7. Offshore Construction UH-1E H7SO 21.25 3/13/92 204 NR 2/12/92 3/13/92 8. Oregon Helicopters UH-1E H4NM 21.25 3/13/92 204 NR 2/12/92 3/13/92 9. Smith Helicopters UH-1E H8NM 21.25 3/13/92 204 NR 2/12/92 3/13/92 10. Southern Aero Corp. UH-1B H3SO 21.25 3/13/92 204 NR 2/12/92 3/13/92 11. West Coast Fabrications UH-1E H9NM 21.25 3/13/92 204 NR 2/12/92 3/13/92 * Or later FAA Approved Revision FAA Approved: Aviation Safety Acting Manager, Technical & Administrative Support Section, Los Angeles ACO Branch REISSUED: December 5, 2011, February 5, 2022 AMENDED: ## Every issue (3) - February 5, 2022: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/8e/af/8eafd7c0911e36c41c2f0d32b6b5b80920b8f71a442066185d1e274f35cefe11), [AML SH5690NM.pdf](https://openairdocs.org/files/sha256/58/81/5881eea738d7c09b9cce46a1d9873cbd76774cd99d175e55ee99caebe15b39f8) - December 5, 2011: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/60/7a/607a2ea835b4c90ce470c8d82f316a722a345986f7c146eb09fb2d4d8d332af8), [AML SH5690NM.pdf](https://openairdocs.org/files/sha256/41/81/418129d8da60624dabc0bc454eac15ecf52b51a92740f0b4df4809a8397771a4) - March 13, 1992: Issued, Historical. [certificate](https://openairdocs.org/files/sha256/b5/37/b5375caefc9bfd821f1ba1dc6fed4a5f6a5bdc4b036be11b12146eb51fb5c073) --- 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.