# STC SH298NW - Type: Supplemental type certificate - Status: Current, Reissued - Holder: Siam Hiller Holdings Inc, United States - Description: Installation and maintenance of a cabin heater system. (UH-12E modified per STC SH178WE) - Applied: March 11, 1976 - Status date: August 19, 2005 - Product: Aircraft, Rotorcraft - Certification basis: Part 21 - Data sheets: [TCDS 4H11](https://openairdocs.org/tcds/4H11) - Certificate PDF: https://openairdocs.org/files/sha256/41/e8/41e89ecafdb946c42130ee3d42802a576cd018f53f0aca2da4b5a3add0477ef7 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/95AB298218FC62C4862570D9005F925F.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/SH298NW ## ADs that name it (0) None. ## Approved models (1) - Rogerson Hiller Corporation UH-12E ([TCDS 4H11](https://openairdocs.org/tcds/4H11)) ## 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 Siam Hiller Holdings, Inc. 925 M Street Firebaugh, California 93622 Part 6 of the Civil Air Regulations. including Amendments 6-1 thru 6-3. 4H11 Hiller UH-12E Description of Type Design Change: Installation and maintenance of a cabin heater system in accordance with FAA approved Soloy Conversions, Ltd. Drawing List 560-301 dated May 14, 1976, or later FAA approved revision. The cabin heater assembly and related brackets must be visually inspected prior to each flight as part of the normal rotorcraft preflight inspection procedure. Refer to the applicable portions of Soloy Conversions, Ltd. Maintenance Manual for the required maintenance of this assembly. NOTE: Only those Hiller UH-12E rotorcraft which have been converted to turbine power in accordance with STC SH178WE are eligible for this modification. Limitations and Conditions: Approval of this change in type design applies to the above model rotorcraft only. This approval should not be extended to other rotorcraft of this model on which other previously approved modifications are incorporated 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 rotorcraft. A copy of this Certificate must be maintained as part of the permanent records for the modified rotorcraft. 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: March 11, 1976 Date of issuance: May 19, 1976 Date reissued: 06/02/83; 10/25/84; 05/28/91; 11/30/95; 08/19/05 Date amended: 05/28/91 ( Signature) Manager, Technical & Administrative Support Staff, Los Angeles Aircraft Certification Office ( Title) ## Every issue (1) - August 19, 2005: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/41/e8/41e89ecafdb946c42130ee3d42802a576cd018f53f0aca2da4b5a3add0477ef7) --- 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.