# STC SH1523SO

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Orlando Heli Airways Inc, United States
- Description: Add approved fuels: unleaded automotive gasoline 87 minimum antiknock index and leaded automotive gasoline, 88 minimum antiknock index (RON & MON)/2. Intermixing with aviation gasoline also approved.
- Status date: December 8, 1983
- Product: Aircraft, Rotorcraft
- Certification basis: Part 21
- Data sheets: [TCDS 1H4](https://openairdocs.org/tcds/1H4)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/20C482E588526AAE85256CC2005C2E9B.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SH1523SO

## ADs that name it (0)

None.

## Approved models (1)

- Sikorsky Aircraft Corporation S-55 ([TCDS 1H4](https://openairdocs.org/tcds/1H4))

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