# STC SA3091SW-D

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Century Flight Systems Inc, United States
- Description: Mitchell automatic flight system AK520 consisting of Century III autopilot with optional radio coupler.
- Status date: June 20, 1984
- Product: Aircraft, Single-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A-2-575](https://openairdocs.org/tcds/A-2-575)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/DC8BEA0615FEF0AA85256CC2000A93B3.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA3091SW-D

## ADs that name it (0)

None.

## Approved models (5)

- Rockwell International Corporation AT-6C (SNJ-4) ([TCDS A-2-575](https://openairdocs.org/tcds/A-2-575))
- Rockwell International Corporation AT-6D (SNJ-5) ([TCDS A-2-575](https://openairdocs.org/tcds/A-2-575))
- Rockwell International Corporation AT-6F (SNJ-6) ([TCDS A-2-575](https://openairdocs.org/tcds/A-2-575))
- Rockwell International Corporation AT-6F (SNJ-7) ([TCDS A-2-575](https://openairdocs.org/tcds/A-2-575))
- Rockwell International Corporation T-6G ([TCDS A-2-575](https://openairdocs.org/tcds/A-2-575))

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