# STC SA155SO

- Type: Supplemental type certificate
- Status: Current, Reissued
- Holder: Avitas Engineering, United States
- Description: Installation of cockpit voice recorder.
- Status date: June 5, 1992
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS 4A25](https://openairdocs.org/tcds/4A25)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/678C54C1541020FC85256CC100821354.0001
- DRS record last changed: December 5, 2025
- Page: https://openairdocs.org/stc/SA155SO

## ADs that name it (0)

None.

## Approved models (2)

- McDonnell Douglas Corporation DC-8-21 ([TCDS 4A25](https://openairdocs.org/tcds/4A25))
- McDonnell Douglas Corporation DC-8-51 ([TCDS 4A25](https://openairdocs.org/tcds/4A25))

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.