# STC ST620CH

- Type: Supplemental type certificate
- Status: Current, Surrendered
- Holder: Lockheed Martin Aircraft Services, United States
- Description: Installation of a Lockheed Martin Water Vapor Sensing System (WVSS). (757-200 PF SERIES)
- Status date: December 1, 2009
- Product: Aircraft, Large Multi-Engine
- Certification basis: Part 21
- Data sheets: [TCDS A2NM](https://openairdocs.org/tcds/A2NM)
- Certificate PDF: https://openairdocs.org/files/sha256/b7/03/b7035626cb0e7b8a734e87ca4522e8f19a1056bed7816305caafe033b61e2bbf
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/37087487F30325C6862576DC0071BCF4.0001
- DRS record last changed: December 6, 2025
- Page: https://openairdocs.org/stc/ST620CH

## ADs that name it (0)

None.

## Approved models (1)

- The Boeing Company 757-200 ([TCDS A2NM](https://openairdocs.org/tcds/A2NM))

## What the certificate says

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

## Every issue (1)

- December 1, 2009: Surrendered, Current. [certificate](https://openairdocs.org/files/sha256/b7/03/b7035626cb0e7b8a734e87ca4522e8f19a1056bed7816305caafe033b61e2bbf)

---
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.