# STC SA1481CE

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Helio Alaska Inc., United States
- Description: Installation of Pratt & Whitney (UACL) PT6A-27 turboprop engine and Hartzell HC-B3TN-3D/T10178CH reversible propeller
- Applied: March 20, 1978
- Status date: August 30, 2024
- Product: Aircraft, Small Airplane
- Data sheets: [TCDS A4EA](https://openairdocs.org/tcds/A4EA)
- Certificate PDF: https://openairdocs.org/files/sha256/2f/90/2f90230e72252296aab6095195afd158fd170e21854cccf865147f7ac969433b
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DRSDOCID185371079320241106141007.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA1481CE

## ADs that name it (0)

None.

## Approved models (1)

- Helio Aircraft LLC HST-550 ([TCDS A4EA](https://openairdocs.org/tcds/A4EA))

## 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.

SA1481CE Helio Alaska, Inc.

20150 Birchwood Spur Rd.

Chugiak, AK 99567 Part 3 the Civil Air Regulations A4EA Helio HST-550 (S/N 1 Only) Installation of Pratt & Whitney (UACL) PT6A turboprop engine and Hartzell HC-B3TN-3D/T10178CH reversible propeller. Data Required: (1) A copy of this certificate; (2) Brent/Helio Drawing 550-080-9000 (Sheet 2 of 4) and Brent Report and Drawings B550-F1; and (3) Airplane Flight Manual Supplement dated March 30, 1979, or later FAA approved revision.

(See Continuation Sheet 3 of 3) March 20, 1978 December 5, 2006; September 12, 2012; October 18, 2012;

August 30, 2024 March 30, 1979 for Paul Nguyen Manager, Central Certification Branch Compliance & Airworthiness Division Aircraft Certification Service 3

SA1481CE 3

SA1481CE Date of Issuance: March 30, 1979 Date of Reissuance: August 30, 2024

(1) Data pertaining to this modification are considered inadequate for duplication in other aircraft. This approval limited to the installation made in Helio HST-550, Serial Number 1 only.

(2) The installer must determine whether this design change is compatible with previously approved modifications. 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.

-END- 3 3

## Every issue (4)

- August 30, 2024: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/2f/90/2f90230e72252296aab6095195afd158fd170e21854cccf865147f7ac969433b)
- October 18, 2012: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/88/ea/88eaf61c5169c3c14dec2ce710e5ed91a2aeef35527b2bb08bf48d075ab23a3c)
- September 12, 2012: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/e5/ed/e5edcc64ba6ea17539f626b4630948028dc89e25283b85558e9b1b0857ec090a)
- December 5, 2006: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/b8/17/b817c9eeb0679eaced5a3762049bae0351599fc4dcdb34c86f253bb8c4e31fd8)

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