# STC SA04587NY - Type: Supplemental type certificate - Status: Current, Issued - Holder: Acorn Welding Ltd., Canada - Description: Installation of Acorn Welding C6SC1107-NG Exhaust stacks - Applied: August 27, 2021 - Status date: October 28, 2021 - Product: Aircraft, Small Airplane - Certification basis: Part 21, Part 23 - Data sheets: [TCDS A9EA](https://openairdocs.org/tcds/A9EA) - Certificate PDF: https://openairdocs.org/files/sha256/69/12/69129442ca1efc8c380682cb6b3b6e636a4ae09deb0534a5600327d60aed66af - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1F70ECF0F7757B73862587800046F30E.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/SA04587NY ## ADs that name it (0) None. ## Approved models (4) - Viking Air Limited DHC-6-100 ([TCDS A9EA](https://openairdocs.org/tcds/A9EA)) - Viking Air Limited DHC-6-200 ([TCDS A9EA](https://openairdocs.org/tcds/A9EA)) - Viking Air Limited DHC-6-300 ([TCDS A9EA](https://openairdocs.org/tcds/A9EA)) - Viking Air Limited DHC-6-400 ([TCDS A9EA](https://openairdocs.org/tcds/A9EA)) ## 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 This certificate issued to: IMPORT SA04587NY Acorn Welding Ltd. 10916 119th Street Edmonton, Alberta Canada T5H 3P4 Title 14 Code of Federal Regulations A9EA Make:Type Certificate Number: Viking Air Limited Model:Description of Type Design Change: DHC-6-100, DHC-6-200, DHC-6-300, DHC-6-400 Limitations and Conditions: 1. Installation of Acorn Welding C6SC1107-NG Exhaust stacks must be done in accordance with Acorn Welding EO-08.01, Rev. 0, dated March 18, 2020, or later Transport Canada Civil Aviation (TCCA) approved revision on DHC-6 Twin Otter aircraft eligible as per prerequisites. Refer to Acorn Welding Drawing C6SC339-08-01, Rev. 0, dated March 3, 2020, or later TCCA approved revision for details. (Description of Type Design Change Continued on Page 3 of 4) 1. If the holder agrees to permit another person to use this certificate to alter a product, the holder must give the other person written evidence of that permission. (Limitations and Conditions Continued on Page 3 of 4) August 27, 2021 Date Reissued: October 28, 2021 Timothy J. Hadsall Acting Manager, New York ACO Branch Compliance & Airworthiness Division Aircraft Certification Service **IMPORT SA04587NY** SA04587NY To (Name and address of transferee): IMPORT SA04587NY Date of Issuance: October 28 2021 Description of Type Design Change (continued): 2. Maintenance must be done in accordance with Acorn Welding ICA # ICA-08-01, Rev. 0, dated June 22, 2018, or later TCCA accepted revision. 2. The installer must determine whether this design change is compatible with previously approved modifications. 3. This STC is applicable to all serial numbers for this Make-Model-Series. 4. Prerequisite: Aircraft MSN 001 thru MSN 230 (Excluding MSN 130 & 210) must be modified by STC SA00837NY, SA01673NY, SA02642LA, SA03265NY, SA5620SW, SA743NE, SA100CH or similar STC replacing the PWC PT6A-20 engines with either PWC PT6A-27 or PWC PT6A-34 engines. 5. This STC is not compatible with the PT6A-20 Engine. 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 Viking Air Limited DHC-6-100, DHC-6-200, DHC-6-300, and DHC-6-400 is as follows: a) The type certification basis for the Viking Air Limited DHC-6-100, DHC-6-200, DHC-6-300, and DHC-6-400 as shown on TCDS A9EA for parts not changed or not affected by the change. b) The type certification basis for the Viking Air Limited DHC-6-100, DHC-6-200, DHC-6-300, and DHC-6-400 as shown on TCDS A9EA for parts changed or affected by the change with the following additional requirements: (Certification Basis Continued on Page 4 of 4) IMPORT SA04587NY Date of Issuance: October 19, 2021 Certification Basis (continued): • Compliance with 14 CFR part 23 in addition to 14 CFR § 23.25 at amendment 23-50 14 CFR § 23.29 at amendment 23-21 14 CFR § 23.251 at amendment 23-62 14 CFR § 23.301 at amendment 23-48 14 CFR § 23.305 at amendment 23-45 14 CFR § 23.307 at amendment 23-0 14 CFR § 23.601 at amendment 23-0 14 CFR § 23.603 at amendment 23-23 14 CFR § 23.605 at amendment 23-23 14 CFR § 23.607 at amendment 23-48 14 CFR § 23.609 at amendment 23-0 14 CFR § 23.611 at amendment 23-48 14 CFR § 23.613 at amendment 23-45 14 CFR § 23.625 at amendment 23-7 14 CFR § 23.1121 at amendment 23-51 14 CFR § 23.1123 at amendment 23-43 14 CFR § 23.1529 at amendment 23-26 ----------END---------- ## Every issue (1) - October 28, 2021: Issued, Current. [certificate](https://openairdocs.org/files/sha256/69/12/69129442ca1efc8c380682cb6b3b6e636a4ae09deb0534a5600327d60aed66af) --- 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.