# STC SA09421AC-D

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: S-TEC Corporation, United States
- Description: Installation of S-TEC system 40X/50X single and two axis automatic flight guidance systems, Model ST-780-40X/50X.
- Status date: February 21, 2000
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 3A15](https://openairdocs.org/tcds/3A15)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B979F93E42401E7185256CC1007F3AF2.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA09421AC-D

## ADs that name it (0)

None.

## Approved models (4)

- Raytheon Aircraft Company S35 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Raytheon Aircraft Company V35 ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Raytheon Aircraft Company V35A ([TCDS 3A15](https://openairdocs.org/tcds/3A15))
- Raytheon Aircraft Company V35B ([TCDS 3A15](https://openairdocs.org/tcds/3A15))

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