# STC ST09957SC

- Type: Supplemental type certificate
- Status: Current, Issued
- Holder: Aircraft Systems & Mfg, United States
- Description: Installation of Innovative Solutions & Support (IS&S) digital air data system consisting of an electric altimeter, Digital Air Data Computer (DADC), Air Data Display Unit (ADDU), and an altitude alerter.
- Applied: June 5, 2001
- Status date: October 16, 2001
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A3WE](https://openairdocs.org/tcds/A3WE)
- Certificate PDF: https://openairdocs.org/files/sha256/e2/5c/e25cdcf258448b1840e3e5f74214506ca2adc617baf3f6c61a87f9d2f2d18270
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/3A02C495A34CB83B85256CC300035EE8.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST09957SC

## ADs that name it (0)

None.

## Approved models (2)

- The Boeing Company 727-100 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))
- The Boeing Company 727-200 Series ([TCDS A3WE](https://openairdocs.org/tcds/A3WE))

## What the certificate says

The certificate is a scan without a text layer; open the PDF to read it.

## Every issue (1)

- October 16, 2001: Issued, Current. [certificate](https://openairdocs.org/files/sha256/e2/5c/e25cdcf258448b1840e3e5f74214506ca2adc617baf3f6c61a87f9d2f2d18270)

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