# STC SA1331WE

- Type: Supplemental type certificate
- Status: Current, Amended
- Holder: Frontier Airlines, Inc, United States
- Description: Installation of United Data Control, Inc. Model V-557 cockpit voice recorder system.
- Status date: March 28, 1967
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 6A6](https://openairdocs.org/tcds/6A6)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5F3BFE1D1FED4C1E85256CC100820F03.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/SA1331WE

## ADs that name it (0)

None.

## Approved models (2)

- Tracor Flight Systems Inc. 340 ([TCDS 6A6](https://openairdocs.org/tcds/6A6))
- Tracor Flight Systems Inc. 440 Military C-131E ([TCDS 6A6](https://openairdocs.org/tcds/6A6))

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